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2010 - 2011: Earth's most extreme weather since 1816?

Posted on 27 June 2011 by Jeff Masters

Every year extraordinary weather events rock the Earth. Records that have stood centuries are broken. Great floods, droughts, and storms affect millions of people, and truly exceptional weather events unprecedented in human history may occur. But the wild roller-coaster ride of incredible weather events during 2010, in my mind, makes that year the planet's most extraordinary year for extreme weather since reliable global upper-air data began in the late 1940s. Never in my 30 years as a meteorologist have I witnessed a year like 2010--the astonishing number of weather disasters and unprecedented wild swings in Earth's atmospheric circulation were like nothing I've seen. The pace of incredible extreme weather events in the U.S. over the past few months have kept me so busy that I've been unable to write-up a retrospective look at the weather events of 2010. But I've finally managed to finish, so fasten your seat belts for a tour through the top twenty most remarkable weather events of 2010. At the end, I'll reflect on what the wild weather events of 2010 and 2011 imply for our future.

Earth's hottest year on record
Unprecedented heat scorched the Earth's surface in 2010, tying 2005 for the warmest year since accurate records began in the late 1800s. Temperatures in Earth's lower atmosphere also tied for warmest year on record, according to independent satellite measurements. Earth's 2010 record warmth was unusual because it occurred during the deepest solar energy minimum since satellite measurements of the sun began in the 1970s. Unofficially, nineteen nations (plus the the U.K.'s Ascension Island) set all-time extreme heat records in 2010. This includes Asia's hottest reliably measured temperature of all-time, the remarkable 128.3°F (53.5°C) in Pakistan in May 2010. This measurement is also the hottest reliably recorded temperature anywhere on the planet except for in Death Valley, California. The countries that experienced all-time extreme highs in 2010 constituted over 20% of Earth's land surface area.

Figure 1. Climate Central and Weather Underground put together this graphic showing the nineteen nations (plus one UK territory, Ascension Island) that set new extreme heat records in 2010.

Most extreme winter Arctic atmospheric circulation on record; "Snowmageddon" results
The atmospheric circulation in the Arctic took on its most extreme configuration in 145 years of record keeping during the winter of 2009 - 2010. The Arctic is normally dominated by low pressure in winter, and a "Polar Vortex" of counter-clockwise circulating winds develops surrounding the North Pole. However, during the winter of 2009 - 2010, high pressure replaced low pressure over the Arctic, and the Polar Vortex weakened and even reversed at times, with a clockwise flow of air replacing the usual counter-clockwise flow of air. This unusual flow pattern allowed cold air to spill southwards and be replaced by warm air moving poleward. Like leaving the refrigerator door ajar, the Arctic "refrigerator" warmed, and cold Arctic air spilled out into "living room" where people live. A natural climate pattern called the North Atlantic Oscillation (NAO), and its close cousin, the Arctic Oscillation (AO) were responsible. Both of these patterns experienced their strongest-on-record negative phase, when measured as the pressure difference between the Icelandic Low and Azores High.

The extreme Arctic circulation caused a bizarre upside-down winter over North America--Canada had its warmest and driest winter on record, forcing snow to be trucked in for the Winter Olympics in Vancouver, but the U.S. had its coldest winter in 25 years. A series of remarkable snow storms pounded the Eastern U.S., with the "Snowmageddon" blizzard dumping more than two feet of snow on Baltimore and Philadelphia. Western Europe also experienced unusually cold and snowy conditions, with the UK recording its 8th coldest January. A highly extreme negative phase of the NAO and AO returned again during November 2010, and lasted into January 2011. Exceptionally cold and snowy conditions hit much of Western Europe and the Eastern U.S. again in the winter of 2010 - 2011. During these two extreme winters, New York City recorded three of its top-ten snowstorms since 1869, and Philadelphia recorded four of its top-ten snowstorms since 1884. During December 2010, the extreme Arctic circulation over Greenland created the strongest ridge of high pressure ever recorded at middle levels of the atmosphere, anywhere on the globe (since accurate records began in 1948.) New research suggests that major losses of Arctic sea ice could cause the Arctic circulation to behave so strangely, but this work is still speculative.

Figure 2. Digging out in Maryland after "Snowmageddon". Image credit: wunderphotographer chills.

Arctic sea ice: lowest volume on record, 3rd lowest extent
Sea ice in the Arctic reached its third lowest areal extent on record in September 2010. Compared to sea ice levels 30 years ago, 1/3 of the polar ice cap was missing--an area the size of the Mediterranean Sea. The Arctic has seen a steady loss of meters-thick, multi-year-old ice in recent years that has left thin, 1 - 2 year-old ice as the predominant ice type. As a result, sea ice volume in 2010 was the lowest on record. More than half of the polar icecap by volume--60%--was missing in September 2010, compared to the average from 1979 - 2010. All this melting allowed the Northwest Passage through the normally ice-choked waters of Canada to open up in 2010. The Northeast Passage along the coast of northern Russia also opened up, and this was the third consecutive year--and third time in recorded history--that both passages melted open. Two sailing expeditions--one Russian and one Norwegian--successfully navigated both the Northeast Passage and the Northwest Passage in 2010, the first time this feat has been accomplished. Mariners have been attempting to sail the Northwest Passage since 1497, and have failed to accomplish this feat without an icebreaker until the 2000s. In December 2010, Arctic sea ice fell to its lowest winter extent on record, the beginning of a 3-month streak of record lows. Canada's Hudson Bay did not freeze over until mid-January of 2011, the latest freeze-over date in recorded history.

Figure 3. The Arctic's minimum sea ice extent for 2010 was reached on September 21, and was the third lowest on record. Image credit: National Snow and Ice Data Center.

Record melting in Greenland, and a massive calving event
Greenland's climate in 2010 was marked by record-setting high air temperatures, the greatest ice loss by melting since accurate records began in 1958, the greatest mass loss of ocean-terminating glaciers on record, and the calving of a 100 square-mile ice island--the largest calving event in the Arctic since 1962. Many of these events were due to record warm water temperatures along the west coast of Greenland, which averaged 2.9°C (5.2°F) above average during October 2010, a remarkable 1.4°C above the previous record high water temperatures in 2003.

Figure 4. The 100 square-mile ice island that broke off the Petermann Glacier heads out of the Petermann Fjord in this 7-frame satellite animation. The animation begins on August 5, 2010, and ends on September 21, with images spaced about 8 days apart. The images were taken by NASA's Aqua and Terra satellites.

Second most extreme shift from El Niño to La Niña
The year 2010 opened with a strong El Niño event and exceptionally warm ocean waters in the Eastern Pacific. However, El Niño rapidly waned in the spring, and a moderate to strong La Niña developed by the end of the year, strongly cooling these ocean waters. Since accurate records began in 1950, only 1973 has seen a more extreme swing from El Niño to La Niña. The strong El Niño and La Niña events contributed to many of the record flood events seen globally in 2010, and during the first half of 2011.

Figure 5. The departure of sea surface temperatures from average at the beginning of 2010 (top) and the end of 2010 (bottom) shows the remarkable transition from strong El Niño to strong La Niña conditions that occurred during the year. Image credit: NOAA/NESDIS.

Second worst coral bleaching year
Coral reefs took their 2nd-worst beating on record in 2010, thanks to record or near-record warm summer water temperatures over much of Earth's tropical oceans. The warm waters caused the most coral bleaching since 1998, when 16 percent of the world's reefs were killed off. "Clearly, we are on track for this to be the second worst (bleaching) on record," NOAA coral expert Mark Eakin in a 2010 interview. "All we're waiting on now is the body count." The summer 2010 coral bleaching episodes were worst in the Philippines and Southeast Asia, where El Niño warming of the tropical ocean waters during the first half of the year was significant. In Indonesia's Aceh province, 80% of the bleached corals died, and Malaysia closed several popular dive sites after nearly all the coral were damaged by bleaching. In some portions of the Caribbean, such as Venezuela and Panama, coral bleaching was the worst on record.

Figure 6. An example of coral bleaching that occurred during the record-strength 1997-1998 El Niño event. Image credit: Craig Quirolo, Reef Relief/Marine Photobank, in Climate, Carbon and Coral Reefs

Wettest year over land
The year 2010 also set a new record for wettest year in Earth's recorded history over land areas. The difference in precipitation from average in 2010 was about 13% higher than that of the previous record wettest year, 1956. However, this record is not that significant, since it was due in large part to random variability of the jet stream weather patterns during 2010. The record wetness over land was counterbalanced by relatively dry conditions over the oceans.

Figure 7. Global departure of precipitation over land areas from average for 1900 - 2010. The year 2010 set a new record for wettest year over land areas in Earth's recorded history. The difference in precipitation from average in 2010 was about 13% higher than that of the previous record wettest year, 1956. Image credit: NOAA's National Climatic Data Center.

Amazon rainforest experiences its 2nd 100-year drought in 5 years
South America's Amazon rainforest experienced its second 100-year drought in five years during 2010, with the largest northern tributary of the Amazon River--the Rio Negro--dropping to thirteen feet (four meters) below its usual dry season level. This was its lowest level since record keeping began in 1902. The low water mark is all the more remarkable since the Rio Negro caused devastating flooding in 2009, when it hit an all-time record high, 53 ft (16 m) higher than the 2010 record low. The 2010 drought was similar in intensity and scope to the region's previous 100-year drought in 2005. Drought makes a regular appearance in the Amazon, with significant droughts occurring an average of once every twelve years. In the 20th century, these droughts typically occurred during El Niño years, when the unusually warm waters present along the Pacific coast of South America altered rainfall patterns. But the 2005 and 2010 droughts did not occur during El Niño conditions, and it is theorized that they were instead caused by record warm sea surface temperatures in the Atlantic.

We often hear about how important Arctic sea ice is for keeping Earth's climate cool, but a healthy Amazon is just as vital. Photosynthesis in the world's largest rainforest takes about 2 billion tons of carbon dioxide out of the air each year. However, in 2005, the drought reversed this process. The Amazon emitted 3 billion tons of CO2 to the atmosphere, causing a net 5 billion ton increase in CO2 to the atmosphere--roughly equivalent to 16 - 22% of the total CO2 emissions to the atmosphere from burning fossil fuels that year. The Amazon stores CO2 in its soils and biomass equivalent to about fifteen years of human-caused emissions, so a massive die-back of the forest could greatly accelerate global warming.

Figure 8. Hundreds of fires (red squares) generate thick smoke over a 1000 mile-wide region of the southern Amazon rain forest in this image taken by NASA's Aqua satellite on August 16, 2010. The Bolivian government declared a state of emergency in mid-August due to the out-of-control fires burning over much of the country. Image credit: NASA.

Global tropical cyclone activity lowest on record
The year 2010 was one of the strangest on record for tropical cyclones. Each year, the globe has about 92 tropical cyclones--called hurricanes in the Atlantic and Eastern Pacific, typhoons in the Western Pacific, and tropical cyclones in the Southern Hemisphere. But in 2010, we had just 68 of these storms--the fewest since the dawn of the satellite era in 1970. The previous record slowest year was 1977, when 69 tropical cyclones occurred world-wide. Both the Western Pacific and Eastern Pacific had their quietest seasons on record in 2010, but the Atlantic was hyperactive, recording its 3rd busiest season since record keeping began in 1851. The Southern Hemisphere had a slightly below average season. The Atlantic ordinarily accounts for just 13% of global cyclone activity, but accounted for 28% in 2010--the greatest proportion since accurate tropical cyclone records began in the 1970s.

A common theme of many recent publications on the future of tropical cyclones globally in a warming climate is that the total number of these storms will decrease, but the strongest storms will get stronger. For example, a 2010 review paper published in Nature Geosciences concluded that the strongest storms would increase in intensity by 2 - 11% by 2100, but the total number of storms would fall by 6 - 34%. It is interesting that 2010 saw the lowest number of global tropical cyclones on record, but an average number of very strong Category 4 and 5 storms (the 25-year average is 13 Category 4 and 5 storms, and 2010 had 14.) Fully 21% of 2010's tropical cyclones reached Category 4 or 5 strength, versus just 14% during the period 1983 - 2007. Most notably, in 2010 we had Super Typhoon Megi. Megi's sustained winds cranked up to a ferocious 190 mph and its central pressure bottomed out at 885 mb on October 16, making it the 8th most intense tropical cyclone in world history. Other notable storms in 2010 included the second strongest tropical cyclone on record in the Arabian Sea (Category 4 Cyclone Phet in June), and the strongest tropical cyclone ever to hit Myanmar/Burma (October's Tropical Cyclone Giri, an upper end Category 4 storm with 155 mph winds.)

Figure 9. Visible satellite image of Tropical Cyclone Phet on Thursday, June 3, 2010. Record heat over southern Asia in May helped heat up the Arabian Sea to 2°C above normal, and the exceptionally warm SSTs helped fuel Tropical Cyclone Phet into the second strongest tropical cyclone ever recorded in the Arabian Sea. Phet peaked at Category 4 strength with 145 mph winds, and killed 44 people and did $700 million in damage to Oman. Only Category 5 Cyclone Gonu of 2007 was a stronger Arabian Sea cyclone.

A hyperactive Atlantic hurricane season: 3rd busiest on record
Sea surface temperatures that were the hottest on record over the main development region for Atlantic hurricanes helped fuel an exceptionally active 2010 Atlantic hurricane season. The nineteen named storms were the third most since 1851; the twelve hurricanes of 2010 ranked second most. Three major hurricanes occurred in rare or unprecedented locations. Julia was the easternmost major hurricane on record, Karl was the southernmost major hurricane on record in the Gulf of Mexico, and Earl was the 4th strongest hurricane so far north. The formation of Tomas so far south and east so late in the season (October 29) was unprecedented in the historical record; no named storm had ever been present east of the Lesser Antilles (61.5°W) and south of 12°N latitude so late in the year. Tomas made the 2010 the 4th consecutive year with a November hurricane in the Atlantic--an occurrence unprecedented since records began in 1851.

Figure 10. Hurricane Earl as seen from the International Space Station on Thursday, September 2, 2010. Image credit: NASA astronaut Douglas Wheelock.

A rare tropical storm in the South Atlantic
A rare tropical storm formed in the South Atlantic off the coast of Brazil on March 10 - 11, and was named Tropical Storm Anita. Brazil has had only one landfalling tropical cyclone in its history, Cyclone Catarina of March 2004, one of only seven known tropical or subtropical cyclones to form in the South Atlantic, and the only one to reach hurricane strength. Anita of 2010 is probably the fourth strongest tropical/subtropical storm in the South Atlantic, behind Hurricane Catarina, an unnamed February 2006 storm that may have attained wind speeds of 65 mph, and a subtropical storm that brought heavy flooding to the coast of Uruguay in January 2009. Tropical cyclones rarely form in the South Atlantic Ocean, due to strong upper-level wind shear, cool water temperatures, and the lack of an initial disturbance to get things spinning (no African waves or Intertropical Convergence Zone.)

Figure 11. Visible satellite image of the Brazilian Tropical Storm Anita.

Strongest storm in Southwestern U.S. history
The most powerful low pressure system in 140 years of record keeping swept through the Southwest U.S. on January 20 - 21, 2010, bringing deadly flooding, tornadoes, hail, hurricane force winds, and blizzard conditions. The storm set all-time low pressure records over roughly 10 - 15% of the U.S.--southern Oregon, California, Nevada, Arizona, and Utah. Old records were broken by a wide margin in many locations, most notably in Los Angeles, where the old record of 29.25" set January 17, 1988, was shattered by .18" (6 mb). The record-setting low spawned an extremely intense cold front that swept through the Southwest. Winds ahead of the cold front hit sustained speeds of hurricane force--74 mph--at Apache Junction, 40 miles east of Phoenix, and wind gusts as high as 94 mph were recorded in Ajo, Arizona. High winds plunged visibility to zero in blowing dust on I-10 connecting Phoenix and Tucson, closing the Interstate.

Figure 12. Ominous clouds hover over Arizona's Superstition Mountains during Arizona's most powerful storm on record, on January 21, 2010. Image credit: wunderphotographer ChandlerMike.

Strongest non-coastal storm in U.S. history
A massive low pressure system intensified to record strength over northern Minnesota on October 26, 2010, resulting in the lowest barometric pressure readings ever recorded in the continental United States, except for from hurricanes and nor'easters affecting the Atlantic seaboard. The 955 mb sea level pressure reported from Bigfork, Minnesota beat the previous low pressure record of 958 mb set during the Great Ohio Blizzard of January 26, 1978. Both Minnesota and Wisconsin set all time low pressure readings during the October 26 storm, and International Falls beat their previous low pressure record by nearly one-half inch of mercury--a truly amazing anomaly. The massive storm spawned 67 tornadoes over a four-day period, and brought sustained winds of 68 mph to Lake Superior.

Figure 13. Visible satellite image of the October 26, 2010 superstorm taken at 5:32pm EDT. At the time, Bigfork, Minnesota was reporting the lowest pressure ever recorded in a U.S. non-coastal storm, 955 mb. Image credit: NASA/GSFC.

Weakest and latest-ending East Asian monsoon on record
The summer monsoon over China's South China Sea was the weakest and latest ending monsoon on record since detailed records began in 1951, according to the Beijing Climate Center. The monsoon did not end until late October, nearly a month later than usual. The abnormal monsoon helped lead to precipitation 30% - 80% below normal in Northern China and Mongolia, and 30 - 100% above average across a wide swath of Central China. Western China saw summer precipitation more than 200% above average, and torrential monsoon rains triggered catastrophic landslides that killed 2137 people and did $759 million in damage. Monsoon floods in China killed an additional 1911 people, affected 134 million, and did $18 billion in damage in 2010, according to the WHO Collaborating Centre for Research on the Epidemiology of Disasters (CRED). This was the 2nd most expensive flooding disaster in Chinese history, behind the $30 billion price tag of the 1998 floods that killed 3656 people. China had floods in 1915, 1931, and 1959 that killed 3 million, 3.7 million, and 2 million people, respectively, but no damage estimates are available for these floods.

Figure 14. Paramilitary policemen help evacuate residents from Wanjia village of Fuzhou City, East China's Jiangxi province, June 22, 2010. Days of heavy rain burst the Changkai Dike of Fu River on June 21, threatening the lives of 145,000 local people. Image credit: Xinhua.

No monsoon depressions in India's Southwest Monsoon for 2nd time in 134 years
The Southwest Monsoon that affects India was fairly normal in 2010, bringing India rains within 2% of average. Much of the rain that falls in India from the monsoon typically comes from large regions of low pressure that form in the Bay of Bengal and move westwards over India. Typically, seven of these lows grow strong and well-organized enough to be labelled monsoon depressions, which are similar to but larger than tropical depressions. In 2010, no monsoon depressions formed--the only year besides 2002 (since 1877) that no monsoon depressions have been observed.

The Pakistani flood: most expensive natural disaster in Pakistan's history
A large monsoon low developed over the Bay of Bengal in late July and moved west towards Pakistan, creating a strong flow of moisture that helped trigger the deadly Pakistan floods of 2010. The floods were worsened by a persistent and unusually-far southwards dip in the jet stream, which brought cold air and rain-bearing low pressure systems over Pakistan. This unusual bend in the jet stream also helped bring Russia its record heat wave and drought. The Pakistani floods were the most expensive natural disaster in Pakistani history, killing 1985 people, affecting 20 million, and doing $9.5 billion in damage.

Figure 15. Local residents attempt to cross a washed-out road during the Pakistani flood catastrophe of 2010. Image credit: Pakistan Meteorology Department.

The Russian heat wave and drought: deadliest heat wave in human history
A scorching heat wave struck Moscow in late June 2010, and steadily increased in intensity through July as the jet stream remained "stuck" in an unusual loop that kept cool air and rain-bearing low pressure systems far north of the country. By July 14, the mercury hit 31°C (87°F) in Moscow, the first day of an incredible 33-day stretch with a maximum temperatures of 30°C (86°F) or higher. Moscow's old extreme heat record, 37°C (99°F) in 1920, was equaled or exceeded five times in a two-week period from July 26 - August 6 2010, including an incredible 38.2°C (101°F) on July 29. Over a thousand Russians seeking to escape the heat drowned in swimming accidents, and thousands more died from the heat and from inhaling smoke and toxic fumes from massive wild fires. The associated drought cut Russia's wheat crop by 40%, cost the nation $15 billion, and led to a ban on grain exports. The grain export ban, in combination with bad weather elsewhere in the globe during 2010 - 2011, caused a sharp spike in world food prices that helped trigger civil unrest across much of northern Africa and the Middle East in 2011. At least 55,000 people died due to the heat wave, making it the deadliest heat wave in human history. A 2011 NOAA study concluded that "while a contribution to the heat wave from climate change could not be entirely ruled out, if it was present, it played a much smaller role than naturally occurring meteorological processes in explaining this heat wave's intensity." However, they noted that the climate models used for the study showed a rapidly increasing risk of such heat waves in western Russia, from less than 1% per year in 2010, to 10% or more per year by 2100.

Figure 16. Smoke from wildfires burning to the southeast of Moscow on August 12, 2010. Northerly winds were keeping the smoke from blowing over the city. Image credit: NASA.

Record rains trigger Australia's most expensive natural disaster in history
Australia's most expensive natural disaster in history is now the Queensland flood of 2010 - 2011, with a price tag as high as $30 billion. At least 35 were killed. The Australian Bureau of Meteorology's annual summary reported, "Sea surface temperatures in the Australian region during 2010 were the warmest value on record for the Australian region. Individual high monthly sea surface temperature records were also set during 2010 in March, April, June, September, October, November and December. Along with favourable hemispheric circulation associated with the 2010 La Niña, very warm sea surface temperatures contributed to the record rainfall and very high humidity across eastern Australia during winter and spring." In 2010, Australia had its wettest spring (September - November) since records began 111 years ago, with some sections of coastal Queensland receiving over 4 feet (1200 mm) of rain. Rainfall in Queensland and all of eastern Australia in December was the greatest on record, and the year 2010 was the rainiest year on record for Queensland. Queensland has an area the size of Germany and France combined, and 3/4 of the region was declared a disaster zone.

Figure 17. The airport, the Bruce Highway, and large swaths of Rockhampton, Australia, went under water due to flooding from the Fitzroy River on January 9, 2011. The town of 75,000 was completely cut off by road and rail, and food, water and medicine had to be brought in by boat and helicopter. Image credit: NASA.

Heaviest rains on record trigger Colombia's worst flooding disaster in history
The 2010 rainy-season rains in Colombia were the heaviest in the 42 years since Colombia's weather service was created and began taking data. Floods and landslides killed 528, did $1 billion in damage, and left 2.2 million homeless, making it Colombia's most expensive, most widespread, and 2nd deadliest flooding disaster in history. Colombia's president Juan Manuel Santos said, "the tragedy the country is going through has no precedents in our history."

Figure 18. A daring rescue of two girls stranded in a taxi by flash flood waters Barranquilla, northern Colombia on August 14, 2010.

Tennessee's 1-in-1000 year flood kills 30, does $2.4 billion in damage
Tennessee's greatest disaster since the Civil War hit on May 1 - 2, 2010, when an epic deluge of rain brought by an "atmospheric river" of moisture dumped up to 17.73" of rain on the state. Nashville had its heaviest 1-day and 2-day rainfall amounts in its history, with a remarkable 7.25" on May 2, breaking the record for most rain in a single day. Only two days into the month, the May 1 - 2 rains made it the rainiest May in Nashville's history. The record rains sent the Cumberland River in downtown Nashville surging to 51.86', 12' over flood height, and the highest level the river has reached since a flood control project was completed in the early 1960s. At least four rivers in Tennessee reached their greatest flood heights on record. Most remarkable was the Duck River at Centreville, which crested at 47', a full 25 feet above flood stage, and ten feet higher than the previous record crest, achieved in 1948.

Figure 19. A portable classroom building from a nearby high school floats past submerged cars on I-24 near Nashville, TN on May 1, 2010. One person died in the flooding in this region of I-24. Roughly 200 - 250 vehicles got submerged on this section of I-24, according to wunderphotographer laughingjester, who was a tow truck operator called in to clear out the stranded vehicles.

When was the last time global weather was so extreme?
It is difficult to say whether the weather events of a particular year are more or less extreme globally than other years, since we have no objective global index that measures extremes. However, we do for the U.S.--NOAA's Climate Extremes Index (CEI), which looks at the percentage area of the contiguous U.S. experiencing top 10% or bottom 10% monthly maximum and minimum temperatures, monthly drought, and daily precipitation. The Climate Extremes Index rated 1998 as the most extreme year of the past century in the U.S. That year was also the warmest year since accurate records began in 1895, so it makes sense that the warmest year in Earth's recorded history--2010--was also probably one of the most extreme for both temperature and precipitation. Hot years tend to generate more wet and dry extremes than cold years. This occurs since there is more energy available to fuel the evaporation that drives heavy rains and snows, and to make droughts hotter and drier in places where storms are avoiding. Looking back through the 1800s, which was a very cool period, I can't find any years that had more exceptional global extremes in weather than 2010, until I reach 1816. That was the year of the devastating "Year Without a Summer"--caused by the massive climate-altering 1815 eruption of Indonesia's Mt. Tambora, the largest volcanic eruption since at least 536 A.D. It is quite possible that 2010 was the most extreme weather year globally since 1816.

Where will Earth's climate go from here?
The pace of extreme weather events has remained remarkably high during 2011, giving rise to the question--is the "Global Weirding" of 2010 and 2011 the new normal? Has human-caused climate change destabilized the climate, bringing these extreme, unprecedented weather events? Any one of the extreme weather events of 2010 or 2011 could have occurred naturally sometime during the past 1,000 years. But it is highly improbable that the remarkable extreme weather events of 2010 and 2011 could have all happened in such a short period of time without some powerful climate-altering force at work. The best science we have right now maintains that human-caused emissions of heat-trapping gases like CO2 are the most likely cause of such a climate-altering force.

Human-caused climate change has fundamentally altered the atmosphere by adding more heat and moisture. Observations confirm that global atmospheric water vapor has increased by about 4% since 1970, which is what theory says should have happened given the observed 0.5°C (0.9°F) warming of the planet's oceans during the same period. Shifts of this magnitude are capable of significantly affecting the path and strength of the jet stream, behavior of the planet's monsoons, and paths of rain and snow-bearing weather systems. For example, the average position of the jet stream retreated poleward 270 miles (435 km) during a 22-year period ending in 2001, in line with predictions from climate models. A naturally extreme year, when embedded in such a changed atmosphere, is capable of causing dramatic, unprecedented extremes like we observed during 2010 and 2011. That's the best theory I have to explain the extreme weather events of 2010 and 2011--natural extremes of El Niño, La Niña and other natural weather patterns combined with significant shifts in atmospheric circulation and the extra heat and atmospheric moisture due to human-caused climate change to create an extraordinary period of extreme weather. However, I don't believe that years like 2010 and 2011 will become the "new normal" in the coming decade. Many of the flood disasters in 2010 - 2011 were undoubtedly heavily influenced by the strong El Niño and La Niña events that occurred, and we're due for a few quiet years without a strong El Niño or La Niña. There's also the possibility that a major volcanic eruption in the tropics or a significant quiet period on the sun could help cool the climate for a few years, cutting down on heat and flooding extremes (though major eruptions tend to increase drought.) But the ever-increasing amounts of heat-trapping gases humans are emitting into the air puts tremendous pressure on the climate system to shift to a new, radically different, warmer state, and the extreme weather of 2010 - 2011 suggests that the transition is already well underway. A warmer planet has more energy to power stronger storms, hotter heat waves, more intense droughts, heavier flooding rains, and record glacier melt that will drive accelerating sea level rise. I expect that by 20 - 30 years from now, extreme weather years like we witnessed in 2010 will become the new normal.

Finally, I'll leave you with a quote from Dr. Ricky Rood's climate change blog, in his recent post,Changing the Conversation: Extreme Weather and Climate: "Given that greenhouse gases are well known to hold energy close to the Earth, those who deny a human-caused impact on weather need to pose a viable mechanism of how the Earth can hold in more energy and the weather not be changed. Think about it."

Reposted from Weather Underground by Dr Jeff Masters, Director of Meteorology.

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Comments 101 to 150 out of 419:

  1. 99, Camburn,
    And if they exagerate, they can justify increasing the premium, hence the profit.
    No, Camburn, in a free market economy, if they exaggerate they lose out to their competitors.
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  2. adelady @95 I checked your Scientific American link and did not see what I was hoping to see. What do they call a climate disaster, what is the criteria, where are they taking place, is it as Tom Curtis states...they take one huge tornadic event that might destroy multiple sites and call this one disaster? Here is all the link provided. "Researchers at the company, which obviously has a keen financial interest in trends that increase insurance risks, add 700 to 1,000 natural catastrophes to the database each year, explains Mark Bove, senior research meteorologist in Munich Re's catastrophe risk management office in Princeton, N.J. The data indicate a small increase in geologic events like earthquakes since 1980 because of better reporting. But the increase in the number of climate disasters is far larger. "Our figures indicate a trend towards an increase in extreme weather events that can only be fully explained by climate change," says Peter Höppe, head of Munich Re's Geo Risks Research/Corporate Climate Center: "It's as if the weather machine had changed up a gear."
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  3. norman, it's just a newspaper report with a brief overview of their work. The important things a) it's obviously a comprehensive database b) they're obviously good at it. Why? Because they're still in business. If they'd been under or over estimating risks they'd have been put out of business either by overcharging for risks and losing customers or by undercharging premiums/ paying out too much on insured events and going bankrupt. Note their overview is pretty general. I doubt very much they'll give away their commercial advantage for nothing. They use the expertise they have to maintain commercial viability. Following their links eventually leads you to an invitiation to sign up for their services. No surprise there, they're not NOAA or NSIDC.
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  4. And if they exagerate, they can justify increasing the premium, hence the profit. This reminds me: I've been amused lately to see a "skeptic" I know -- who normally worships the Free Market -- wringing his hands over the horrible effects of the Profit Motive on professional honesty. It's all very earnest. If I hadn't been hearing the "private vice = public virtue" boilerplate from him for years, I'd almost think he meant it, and wasn't simply eager to beat his opponents with any stick that comes to hand.
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  5. Camburn @91, massive move of the goal posts there, Camburn. I take that as a concession that you have lost the actual argument, which is about extreme weather as the term is used by scientists (and just about everybody else).
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  6. Camburn @91, massive move of the goal posts there, Camburn. I also love the idea of prefacing the comment in question with "IMHO." Whether you're imperiously turning standard scientific language on its head, contradicting experts whose knowledge and experience dwarfs your own, or accusing Munich Re of agreeing with mainstream science for profit, it's important to emphasize your humility.
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  7. Tom: I have not seen anyone here provide a comprehensive deffinition of extreme weather. I posted mine. The variables in climate are such that a few years baseline is not adequate over a climatic period of time to prove anything of substance. That is why I used 500 years. Enough time for the normal variations to even out. Provide a disaster that exceeds that 500 year time now we are talking extreme.....IMHO.
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  8. Norman, I support your position that posts have to be based on scientific evidence but you do come across as trying to desperately find some reason not to accept the science when presented to you. However, in terms in of published science on the subject I so far havent noticed references to Min et al 2011 mentioned at a forum I've just returned from. Does this meet your criteria? Even if you dont agree with the conclusions, the data on extreme precipitation events from 1951-1999 is cause for pause.(note the 8M of supplimentary notes if you are wanting more detail on methods etc). On the insurance industry - I find it interesting to see the insurance industry lobbying for climate action. I liked the Lloyd's quote "the world cannot insure its way out of climate change". Dismissing the Munich Re data as self-serving way to jack up a premiums seems a lot less likely than self-serving in trying to protect against massive payouts. I would trust the insurance industry second only to science for investigating the likely effects of climate change. Have a look at global insurance statements at this site
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  9. camburn "Provide a disaster that exceeds that 500 year time frame..." Provide a disaster?? So you're only interested in severity, not in frequency or persistence? My example isn't even a disaster, but you'll get the idea. Lake Eyre South, in the arid north of South Australia, has filled this year. The third year in a row. (Note, the floods from the Gulf area of Northern Queensland that provide the water are not the catastrophic kind that affected Brisbane and Toowoomba.) 3 years in a row. The normal? 3 times a century. Obviously north Queensland floods more regularly than that, and a lot of the water gets to Lake Eyre North. The big issue is whether it fills all the way across to Lake Eyre South, >9000 sq km. This year the pelicans are partying again. How do you regard floods, droughts, storms the same severity as previously but occurring 10%, 30%, 100% more often?
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  10. Camburn @107, I do not think there is a comprehensive definition of "extreme weather" because I do not think there can be. For some types of events, floods, for example, you can classify rainfall events which exceed two standard deviations from the mean as extreme. For others such as thunderstorms, that is not so clear. Perhaps exceeding two standard deviations from the mean of wind speeds would make an event extreme, but it is not clear that that is the case. Perhaps a better guide is that any wind strong enough to blow down trees means the accompanying storm is extreme. So the definition of "extreme event" is a little fuzzy. That, however is not a problem because nobody is saying that global warming is causing extreme events, and that they did not occur before. Even for events such as the 2010 Moscow heatwave which had an Annual Exceedance Probability (AEP) of 1 in 260, and the like of which had not occurred in Moscow for over a thousand years, climate scientists say that such events could happen without global warming; that it might not have happened without global warming in this particular case; and that global warming will make such events more frequent. In other words, even for the most extreme events, the argument about global warming's involvement is heavily statistical. Given that, the evidence is clear that there has been an increase in weather related extreme events. Research funded by Munich Re shows a threefold increase in weather related disasters over the last thirty years, and a two fold increase in major weather related disasters (which will not have been under reported). Given the magnitude of those increases, the fuzziness of the definition of an "extreme weather event" is not a major factor. Therefore I think the evidence clearly shows that there has been an increase in extreme weather events over the last thirty years. That does not mean the increase in extreme weather is not just chance. It does not prove that global warming is a factor. Given the evidence available, I think you can rationally believe that AGW is not a factor in the increase in extreme weather events. But I do not believe you can rationally believe there has been no such increase. In this respect, I disagree with Chris Masters when he says, " The best science we have right now maintains that human-caused emissions of heat-trapping gases like CO2 are the most likely cause of such a climate-altering force." Indeed, contrary to Chris Masters, the most likely "weather altering force" that is the predominate cause of the large number of disasters in 2010/11 is the conjunction of a strong El Nino followed immediately by a strong La Nina. But I think the best science we have right now shows that it is likely (>66% probability) that global warming is a significant factor in the increase in extreme weather events generally, and the very large number of extreme events in 2010/11. I believe this because there is a direct causal explanation as to why increased surface temperatures will result in in creased humidity (and hence rainfall). There is also a direct causal explanation as to why increased humidity will increase the strength of convective events. There are also reasonably clear correlations between increased global warmth and increased extreme events generally, and increased frequency and intensity of ENSO oscillations. None of this takes away from the fact that 2010/11 have been extraordinary on any terms, and Masters is probably right that they are the most extreme years since the eruption of Tamboro. But sometimes things happen by chance, at that may still be what this is. Only time will tell. If such extreme years become decadal events, the case that AGW is a factor will become very hard to reject. And if weather related disasters continue to rise as shown by Munich Re, it will become impossible to rationally reject. But we are not at that point yet. What I do know, however, is that it is a mark of the irrational denial of a theory that it cannot accept even the theories rational points. In this case, inability to even accept that extreme events are on the rise despite the mountain of evidence is irrational denial.
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    [DB] Added in a missing bold closing tag (I had to guess as to the intended location).

  11. KR @ 97 My posts are always changing as different views or questions are asked. Some of my posts are based upon someone's specific question. I do try to get global information but it does not seem so easy. As you stated it does take a lot of work to find information. I do keep working on it. My own belief is that weather is not getting any worse as I have lived through many years of variability. My study was Chemistry but I have always been interested in weather and climate. The post above is a list of extreme weather events that took place in 2010. I will attempt some more if you are interested. If not someone else may be. The first point in Jeff Masters post is about the hot temperatures. 19 Nation's set record high temps in 2010. That leaves 176 (of the 195) that did not break a record. I am still working on the other Nations to see what was their record high temps and when did they occur. I stated already on one post, are other record breakers in clusters? At this time it is not known to me if a cluster of 19 national records in one year is super extreme. Need the rest of the data to determine this one. On the AO and NAO I found a link that strongly challenges this as an unusual or extreme event and also has many links to articles (some may be peer-reviewed) that discuss it at greater length. They do explain how blocking patterns are created. I do like that part of this link. AO and NOA information page. I will agree with Jeff Masters on Greenland. Greenland in 2010. ENSO has been talked about already in other posts on this thread. I don't know much about Coral bleaching so I will have to accept this one as stated. His percipitation graph looks highly variable and would suggest that whatever forces are responsible are chaotic and even Jeff Masters does not believe this one is significant. Jeff Masters may have something with the Amazon droughts...very hard for me to find historical information on droughts in the Amazon. One paper describing the cause and another is only an abstract with some graph data...don't want to comment unless I understand the graphs correctly. Abstract on Amazonian droughts with some graphs. Causes of 2005 Amazon drought. I always like to read causes and links, more satisfying. Floods in China are not extreme events. On a previous link I posted there was a flood in China every other year. Floods in Pakistan are quite frequent. 2010 may have been the worst in recent history but it is not an unusual event to have floods there. Pakistan's recent floods. Guess that is enough for now. I will have to see what your response is to what I posted.
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  12. Camburn @99, Munich Re is a re-insurer. That means they do nt sell insurance to the general public, but to other insurance companies who have their own statistics on the frequency of extreme events. Consequently, if Munich Re was distorting the data, that would only result in their clients not trusting them.
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  13. Camburn...a once in 500 year event is extreme? Do you have any idea what kind of damage that is? Cf. Hurricane Katrina, which wasn't even close to a one in 500 year event. Just ludicrous argumentation.
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  14. adelady: How do I regard floods, droughts etc as occuring more often? 1st.....I want to see the data set that provides the baseline that establishes that they are "more often". Once that is established, and accepted, then there is something to compare. And once that is accepted, then one can look at the cause relationship to the result. Previous history of the Lake, according to wiki, shows that it can fill more often than three times a century. "In strong La Niña years the lake can fill. Since 1885 this has occurred in 1886–1887, 1889–1890, 1916–1917, 1950, 1955, and 1974–1976,[1] with the highest flood of 6 m (20 ft) in 1974. Local rain can also fill Lake Eyre to 3–4 m (10–13 ft) as occurred in 1984 and 1989. Torrential rain in January 2007 took about six weeks to reach the lake but put only a small amount of water into it.[2] Wave-built shingle terraces on the shore suggest that during the Medieval Warm Period and centuries immediately prior Lake Eyre possibly held permanent water at levels above those of 1974." If it remains full, it would appear that we are approaching MWP conditions.
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  15. mclanb6: Hurricane Katrina was bad because of where it hit, a major population center. New Orleans levy and dike system needed upgrading, which was well known. If Katrina had hit 200 miles east or west, the damage would have been much less. This is considered a costly event because of where landfall was achieved.
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  16. Tom@110: The Insuance company report is not a scientific report. It is an economic report. Just as the Missouri River flooding today, while devestating to the communities along the river is certainly not an extreme event. There were multiple floods during the period between 1951 and 1995. Since then, the flood of today is the 1st repeat of any magnitude. Local yes, but a large watershed. I see reports of what some reporter will call an extreme event, but as Norman, I can find no credible scientific data showing that over climatic times there has been a sudden jump in actual events. Yes, dollar amounts have gone up, but that is a factor of population/infrastructure etc density increase as far as I can tell.
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  17. Camburn: And? An above-average, but not historically strong, hurricane was able to cause extreme devastation because it made landfall at a major population center. But for you, unless the storm is orders of magnitude stronger, it's not extreme. You pick a random number that will likely never occur (and as importantly, there's probably no way of knowing--or it would be very difficult to know based existing records--whether a recent storm was a once in a 500 year event) simply so you can avoid being persuaded of the problem.
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  18. Camburn @116, I refer you again to my post 55 above. The charts shown come from a scientific paper. They do not show increase in dollar values, but increase in events. The increase is not small. It is a threefold increase for all weather related disasters, and a two fold increase for major weather related disasters. It was checked for observational artifacts by looking at only major disasters, and by looking at the figures for an advanced western nation that has been densely populated through out the observational period (Germany), with a large trend persisting in both cases. Finally, the database is not small, consisting of nearly 20 thousand events. You can only not find scientific data because you carefully turn your eyes away from any that you see.
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  19. Camburn, you seem to have ignored papers I posted not to mention those referenced in the IPCC reports. How about the Min 1951-1999 data set?
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  20. Tom: I missed your posted paper, and shall read it. scaddenp.....must have missed yours as well. Will look at them and read them. mclamb6: Nope, the reason for the 500 year event is to filter out the noise. You cannottttttt make a good assumption on anything on a short time period.
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    [DB] "You cannottttttt make a good assumption on anything on a short time period."

    Scientists and time-series analysts can often make detailed, accurate assessments based on actual analysis.

    You are the one making assumptions, based on the lack of analysis on your part.  And those assumptions so far have not been good ones.

    An example of a long-term trend would be that we are in the midst of a run of 315 consecutive months (since February 1985 and counting) with a global temperature above the 20th century average.  That, my friend, is a trend. 

  21. Lake Eyre has 2 sections, Camburn. For much of last century it was believed that one part was permanently dry. Then it was regarded as unusual when the water made it undeniable. Now? Who knows? Many Australians travelled there 3 years ago because it's a 'once in a lifetime' event. Not at the monent it's not.
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  22. Norman - "Jeff Masters may have something with the Amazon droughts...very hard for me to find historical information on droughts in the Amazon. One paper describing the cause and another is only an abstract with some graph data...don't want to comment unless I understand the graphs correctly" See Amazon drought - A death spiral? - parts 1 - 3 In the process of writing further chapters, but drought is likely being driven by the anomalous warming of the tropical Atlantic, and Eastern/Central Pacific sea surface. Historical extreme droughts have, of course, occurred before, but not 2 1-in-a-100 year events spaced so closely together. If El Nino takes hold later this year (coupled with the warm tropical Atlantic) we may see yet another extraordinary Amazon drought next year. We'll see I guess.
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  23. Rob Painting @ 122 I looked at your article on the Amazon drought cycle. I do like those type of articles. Here is a new research project taking place right now to determine what is going on in the Amazon. The reason I can't find any information of the history of Amazon droughts is because there isn't any. Project development to investigate Amazon droughts. The Phrase "100 year event" may not be valid with the Amazon since I do not know if they have records of past droughts and severity of them.
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  24. Camburn: The idea that a 1 in 100 event is "noise" is silly. Again, it's you picking an absolutely random number where people will have difficulty establishing the occurrence of such events in order to insulate yourself from accurately considering the evidence. Because the next step is this: "Oh, we just had two 500 year events in the last decade? Well, I guess that's probably noise. It's not extreme unless we have a 1 in 1000 year event."
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  25. scaddenp @ 108 The only thing with your link to increased precipitaion from the magazine Nature is that Jeff Masters already has a graph of land precipitation on his post and it does not show an upward trend. It shows a cyclic trend. Wet and dry years. Do these sources conflict? I guess the Nature article is about North American precipitation and the other could be global. I also looked at your insurance links. They use Munich Re as a source.
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    [DB] Munich Re's position as an entity of reference has already been established on this thread, despite ideologocial positions to the contrary.

  26. Norman -"The Phrase "100 year event" may not be valid with the Amazon since I do not know if they have records of past droughts and severity of them" Of course they do, the drought of 1926 was particularly severe. And we have proxy indicators going back before record-keeping. None of as good as current measurements, such as satellites, but the tree-ring research in the tropics is not new: Teleconnection between tree growth in the Amazonian floodplains and the El Niño–Southern Oscillation effect - Schongart 2004 From the abstract (thought I had a copy of the full paper, but can't locate it) " We present a more than 200-year long chronology, which is the first ENSO-sensitive dendroclimatic proxy of the Amazon basin and permits the dating of preinstrumental El Niño events. Time series analyses of our data indicate that during the last two centuries the severity of El Niño increased significantly" For the Amazon that means drought - as discussed in the Amazon Death Spiral series. I believe Tom Curtis has also linked to this study: A history of ENSO events since A.D. 1525: implications for future climate change - Gergis & Fowler 2008 From the abstract: "Although extreme ENSO events are seen throughout the 478-year ENSO reconstruction, approximately 43% of extreme and 28% of all protracted ENSO events (i.e. both El Niño and La Niña phase) occur in the 20th century. The post-1940 period alone accounts for 30% of extreme ENSO years observed since A.D. 1525" And of course the Amazon region has been warming at twice the global average since the 1970's, which promotes further drying. There's a whole bunch of ground I'll cover in the upcoming chapters, but it's a very consistent picture that emerges - the Amazon may be in big trouble.
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  27. This thread has grown tiresome. Norman doesn't believe that we can be sure about increased extreme weather events until 2511, when we have 500 years of careful, scientific and well quantified records of all possible events. Everyone else thinks that the atmospheric physics behind greenhouse gases indicate that the planet must warm as a result of anthropogenic CO2, that we are seeing exactly that warming, as predicted, that history and modern observations show that that degree of warming will be 3˚C or more if we double CO2 levels, and... that this will have nasty, negative effects on our civilized lives. Norman thinks that the droughts, floods, storms, wild fires, heat waves, melting ice and shifting extremes that we see today are possibly caused by climate change, but may just be weather, because he's seen droughts, floods, storms, wild fires, heat waves, melting ice and shifting extremes before, or at least, he thinks he has. Everyone else also thinks that the droughts, floods, storms, wild fires, heat waves, melting ice and shifting extremes that we see today are each, in and of themselves, just the sort of strange extreme weather that one sees everywhere, every year, some place or another. But everyone else also thinks that the bizarre confluence of these events, all at once, all over the globe, and not merely to the extreme, but far too often at actual record-setting levels, suggests that we are seeing the mere beginning of the dark, deadly hole that we are digging for ourselves. Norman doesn't see this. He sees news. He sees other people suffering from the same random, natural disasters that we've all been "entertained" with on and in the news, every year, our entire lives, while we sit comfortably saying "poor souls" and opening another beer. Everyone else sees their own future, or that of people they know, in each and all of these events. Everyone else thinks it's time to stop waffling and vacillating and ignoring the obvious, because in a little while it's going to be too late. Everyone else thinks that some day it's going to be Norman, or ourselves, or both that we're watching on the news, and we're going to feel as sorry for him and ourselves then as we feel for all of the victims now, even if it will be his own damned fault, and ours for our failure to make things clear to him and people like him soon enough to make a difference.
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  28. Sphaerica @ 127 Sorry the 500 year for extreme events (to filter noise) was from Camburn. We are not one and the same. He lives in North Dakota and I live close to Omaha, Nebraska. The question I am asking is one of historical perspective and it does not come from watching disater from the news. So far the Munich Re report is the most used source of data on this thread. It shows weather related disasters are increasing in frequency. The article I linked to that Tom Curtis responded to in post 55 states that with normalized data they cannot determine if disasters are actually increasing at this time. There is not enough information to determine if the weather has become more extreme. The Munich Re report is about disasters. More people and more wealth could be the cause. I am still seeking a report of providing that weather events are becoming more extreme. As I posted earlier, I do not think the human race should not take action on energy needs. Seeking alternative forms of energy is a great idea and I am in favor of it. These extreme weather posts have an interest for me as I have already been researching the topic countering so many claims that it is all HAARP. I have been looking for historical trends before this thread was put up and I will continue looking.
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  29. Norman - "Munich Re report ... shows weather related disasters are increasing in frequency. The article I linked to that Tom Curtis responded to in post 55 states that with normalized data they cannot determine if disasters are actually increasing at this time. ...More people and more wealth could be the cause." It's well worth looking at the change in earthquake disasters (which should be pretty independent of climate change) versus the change in weather disasters. Weather disasters are increasing considerably faster, well above the 'people and more wealth' effect on earthquake accounting. In other words, use the earthquake rates to normalize the weather rates to actual change in weather extremes. All in all, though, this is really a side topic. It seems quite possible that climate change is increasing the severity of weather events, but that's going to take a lot of data (and hence time) for a trend to emerge from the noise. I consider it much more worthwhile to examine changes with higher signal to noise ratios, such as tracking ice retreat, ocean heat content, global temperatures, growth zones, etc.
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  30. Adelady, Thanks for the link to the SciAm article; I was thinking to make the same link. Trenberth has an interesting quote in the story. I wonder if the remark was based on work already published, or to be published some time in the near future. Regarding your concern over the Pine Island Glacier, I have some musings, but I wonder if we could get someone like MSPelto or yourself to draft an article for this site. My musings are along the lines that I've been thinking of the limiting factor of the PIG retreat being more related to outflow and ice viscosity, but if there is melt-water rolling to the surface, then that limiting fact might be made moot. If that is what is happening, then the limiting factor might become how much saline water can flow into the underneath of the PIG. I can't guess what that limit is because the less saline water flowing to the surface will create a conveyor flow for new, higher saline water to flow into the underneath part. If the PIG is undermined enough, the ice above would loose its support and a fairly rapid calving front would develop. If such a situation occurs, previous estimates of the rate of retreat to expect, if they were constrained by ice flow dynamics, could be seriously shy of the mark. And that would imply that the rate of sea level rise... The article could be titled something like, "When the PIG Flies". (Or has that been used already?)
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  31. More extreme weather recently? This post from Florida State seems to have a contrary view.
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  32. studentnigel, what do you make of Maue's work? What does it mean to you and your understanding of climate? What do you take from it?
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  33. Sphaerica @88, Like your thoughts and insights on this (yes, early days indeed), and the analogy is great. Thanks for that.
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  34. StudentNigel @131, Your posts adds nothing to the thread-- in fact it smacks of trolling/baiting. Regardless, you are also making the mistake of citing one source about one weather phenomenon and because that papers makes the case that a particular weather phenomenon is not on the increase you seem to be falsely concluding that all extreme weather phenomena are not on the increase. AGW is about considering the body of evidence, and the evidence does show a marked increase in extreme heat, extreme precipitation and drought.
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  35. #127, Sphaerica, it's a false dichotomy to be either in favor of climate action or to be callously "opening another beer" while watching disasters on TV. The main reason is that I, and perhaps Norman, feel that we can best help people cope with disaster by helping them increase their resilience. A few policy changes would help like emptying out the dams in April and May rather than hoping for a slow melt of record snows. Norman and I both realize that disasters will happen regardless of any actions we take on climate. For example natural blocking weather patterns have played a role in many disasters. Even if the frequency of those disasters is increased, that doesn't really change the cost of preparation. The magnitude of the disasters is the obvious potential long term concern. I could certainly be accused of being callous about that potential threat, but it is one abstract threat of many.
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  36. Way up thread people were asking about the source of Trenberth's much quoted 4% increase in atmospheric moisture. The science behind this statement was published in a paper by Trenberth et al. (2005) in Climate Dynamics. If one looks more closely at the stats. it turns out that is estimate of 4% may be on the conservative side.
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  37. studentnigel.... You might try actually reading the article posted here from Dr Masters before you comment. Under the heading: "Global tropical cyclone activity lowest on record" he clearly makes statements that are consistent with Dr Maue's paper.
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  38. KR @ 129 I have been debating the earthquake point with Tom Curtis. My final post on it was at 94. Tom Curtis did come up with good arguments but I did not see a comment to my final response to his points.
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  39. Norman - I believe that is because your last post was various thoughts on damage per Richter number and distance, rather than observed frequency of 'extreme events' recorded by the insurance industry. I'm not surprised you didn't receive a direct reply to that. I don't believe that the number or strength of earthquakes have increased over time, although population spread and (in the other direction) building codes have affected the damage thereof. As I stated earlier, you can use observed 'extreme events' from earthquakes to scale population and construction effects out of other extreme events.
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  40. Albatross @ 134 "AGW is about considering the body of evidence, and the evidence does show a marked increase in extreme heat, extreme precipitation and drought." Does the evidence really show this? Here is a report on British Columbia long term climate... There were some very big fires in the past. British Columbia drought history. Here is one with droughts across North America. In the text they explain that the causes of drought in North America were also responsible for Global Climate patterns (more rain in some areas droughts in others). From this study it states there were much worse droughts in the past than today. They also have graphs at the end of the article which show 1000 years of droughts. I would challenge you to find an increase in frequency of droughts today as compared to the long 1000 year history. 1000 years of drought record for North America. Have not found data on the Heat waves of the past. I know in the US there were plenty in the 1930's decade. This report on the Missouri river has a graph of the drainage from the entire Missouri river basin since 1900. If you remove maybe three years from the graph (anomalous high peaks, there is no upward trend but there are clear wet and dry cycles). 2011 was a super wet year but anomalies happen. If this event would happen for a few years then I would totally agree with most posters. The point of this graph is please show where moisture is increasing. This is not just a small local area, it covers serveral square miles and should contain a clear signal of moisture increase or decrease to be considered extreme. Missouri River Basin drainage data.
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  41. Norman: I looked over your Missouri drainage data. I can see no reason for your judgement of "anomalous high peaks". The four highest peaks have happened since 1979, with the events in 1997 and this year shattering all the records that went before. In the information you have shown to us, have been twice as many high water events in the 33 years since 1979 as in the 80 years prior to that in the record. I can see a clear temporal consistency of these events which suggests that they are not anomalous except in relation to what went before. In other words, together with other worldwide data, these events represent evidence that the climate is changing. As for the issue of droughts in the Missouri basin, I regard that as relevant only if climate models consistently predict increasing droughts in that region. For instance, where I live, in North America's Pacific Northwest, climate change is predicted to bring more rain.
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  42. Norman, you complained people were not showing you papers with "proper science". I can only assume you didnt read Min. What is shown there is NH data (because that is where measuring network is well-established enough to provide data that can be looked at in standardized way - ie science. See the supplementary section). What shows there is trends, it is not "cycles". It is the best proper analysis of extreme precipitation events on a large scale (not just the USA (2% world area) that I am aware of and its not comforting. On insurance. You were dismissing insurance material on the basis of imagined motivation - I was presenting evidence for alternative more likely motivation. Insurance lobbying of governments for action on climate change is about them protecting their investment. Perhaps it time to tell us what data would change your mind so that we know there is some point in continuing to present evidence.
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  43. Norman @140, Why oh why do you repeatedly insist on missing the point? The situation has been repeatedly explained to you, yet you insist with this position. That is not "skepticism"...and I for one am getting rather tired of this tired old "skeptic" and denier of AGW trick. Your argument , if one could even call it that, that because there were fires in the past means that we can not be causing fires now, or that we are not worsening existing situations now or into the future, is a logical fallacy. You mention BC forests. If I recall correctly, the dire pine beetle infestation that has destroyed swaths of BC's forests has been exacerbated by the marked warming, especially during the cold season, and may have set in motion a positive feedback loop in the Carbon cycle. See for example, Kurz et al. (2008, Nature).
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  44. scaddenp @142 I could only get an abstract to your article and from the reading it seems a model is used as opposed to direct measurements. Plus Jeff Masters already has a global precipitation chart in his article. It has 2010 as an extreme year over land but the graph does not look like an upward trend. I see cycles, dry and wet but I do not see any noticeable or certain upward trend in his graph. On the Insurance links. This issue is still up for debate. Even the Munich Re webpage that Tom Curtis linked to give multiple reasons as to explain why disasters are increasing. Climate Change is one of the possibilities. My strongest objection is it is an indirect proxy for measuring actual weather extremes. Weather extremes may be increasing and then they might not be. Too many other variables in the mix of what a disaster is. I have been asking for just the actual extreme weather events and a trend in these. Is there a chart out there in cyberspace that shows the number of floods a year increasing, or that the intensity of the flooding is going up as compared with previous years. Is there a chart of severe storms (as defined by meteorlogists) that show that the number and intensity is increasing? This is what I would call strong science. Direct evidence of the claim made Global warming is increasing extreme weather related events. So if you have direct (not modeled) evidence that precipitation is increasing that would help, but as I stated Jeff Masters already has a global chart up.
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  45. FatherTheo @141 Maybe it does show a marked change and then again maybe not. When you deal with weather events, any single weather event (tornado, heavy rain etc) is created from a complex of many forces. Many factors go into a weather event (temperature, humidity, wind structure, cold lifting air, jet stream) all of which are variable and may influence each other. You remember the old physics experiment when you have a water bath and generate waves. The average wave height is a product of the energy input. But you can have constructive interference and generate waves much bigger than the average. You see a trend in the Missouri river drainage graph. Then look at this one. Weather is chaotic. Now look at the trend of this graph. Look at 1953 a peak above the rest (now compare your analysis to the Missouri river basin) then 1957 is above that. Then in 1965 maybe double the normal. Then 1974 stands out like a sore thumb. Proof positive the climate is changing for the worse and we will all soon be killed....whoops but then look what happens after that, everything goes back to normal until 2011. I believe you can see this random and wide fluctuations on most historical weather data. I compiled a little excel graph of snowfall in Omaha. You have these 3 huge peaks and then it never gets up there again. If you do not accept this I will find more historical graphs of weather related events and show to you that it is indeed how it works. The 2011 heavy rains were just like the biggest wave in the tank of water. All the right elements came together to produce the very heavy rainfall in the Missouri river basin. As I stated it this occurs a few more times I will think you are correct. My tornado graph was a demonstration of seeing trends were there may be none. Hope that clears it up for you.
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  46. Norman @123, the most extensive direct record of Amazon water states is from the river gauge at Manaus. That provides a continuous record of river levels for the Rio Negro, a major Amazon tributary, since 1903. The record is analysed by Richey et al 2004. The data through 2009 is available on a spreadsheat, in which river depths are given in centimetres. Analysing that data, the low river point in 2005 was 1.78 standard deviations below the mean, while in 2010 it was over 2.5 standard deviations below the mean. That gives an incomplete picture of the droughts. The 2005 and 2010 droughts where unusual both as to the location of the rainfall deficit and to their timing. In particular, their timing correlated with El Neno's, whereas, the 2005 and 2010 droughts correlated with La Nina's and where probably caused by unusually warm tropical Atlantic sea water. More importantly for this point is that, unusually for Amazon droughts, the 2005 droughts had low water simultaneously in all its tributaries (see abstract below). That means that a measure of river levels, and in particular the standard deviation of just one tributary (the Rio Negro) will understate the impact on the total Amazon flows.
    "Severe hydrological droughts in the Amazon have generally been associated with strong El Nino events. More than 100 years of stage record at Manaus harbour confirms that minimum water levels generally coincide with intense warming in the tropical Pacific sea waters. During 2005, however, the Amazon experienced a severe drought which was not associated with an El Nino event. Unless what usually occurs during strong El Nino events, when negative rainfall anomalies usually affect central and eastern Amazon drainage basin; rainfall deficiencies in the drought of 2005 were spatially constrained to the west and southwest of the basin. In spite of this, discharge stations at the main-stem recorded minimum water levels as low as those observed during the basin-wide 1996–1997 El Nino-related drought. The analysis of river discharges along the main-stem and major tributaries during the drought of 2004–2005 revealed that the recession on major tributaries began almost simultaneously. This was not the case in the 1996–1997 drought, when above-normal contribution of some tributaries for a short period during high water was crucial to partially counterbalance high discharge deficits of the other tributaries. Since time-lagged contributions of major tributaries are fundamental to damp the extremes in the main-stem, an almost coincident recession in almost all tributaries caused a rapid decrease in water discharges during the 2005 event."
    In the entire 108 year record , the Rio Negro has been lower than in 2005 (14.75 m) just 7 times {1906 (14.2 m); 1916 (14.42 m); 1926 (14.52 m); 1958 (14.74 m); 1963 (13.64 m); 1997 (14.34); and 2010 (13.63)}. The 2010 figure is, of course, the record low for the Rio Negro. The occurrence of two such low levels of the Rio Negro in just six years is itself unusual. When you consider that the reduction in the flow of the Amazon itself was even greater in relative terms, that the droughts occurred in an unusual geographic region, that they occurred when, based on the ENSO cycle we would have expected heavier rain rather than ligher, and that between them (2009) the record flood levels for the Amazon were set as well, also unusual as to timing and location, the notion that this is a continuation of "same ol', same ol'" is nonsense. Please note that the droughts of 2005 and 2010 were unusual dry season droughts. The most extreme Rio Negro drought on record was the wet season drought of 1926, in which Rio Negro peak flows were five standard deviations below the normal peak. Nor was 2005 exceptional in terms of total flows over the year, in that an almost normal wet season meant that lower annual flows have been achieved in one if four years. The distinction between wet season and dry season droughts is probably important with regards to impacts on the Amazon forest, but not with regard to the unusual nature of the 2005 and 2010 droughts. (As a side note, 1963 was also a wet season droughts.) More information available here (pdf)
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  47. Albatross @ 143 "Your argument , if one could even call it that, that because there were fires in the past means that we can not be causing fires now, or that we are not worsening existing situations now or into the future, is a logical fallacy." That is not my argument. Sorry that is what you see. My argument is fairly simple. Jeff Masters posted some severe weather events of 2010. He used these events to make the conclusion "The pace of extreme weather events has remained remarkably high during 2011, giving rise to the question--is the "Global Weirding" of 2010 and 2011 the new normal? Has human-caused climate change destabilized the climate, bringing these extreme, unprecedented weather events? Any one of the extreme weather events of 2010 or 2011 could have occurred naturally sometime during the past 1,000 years. But it is highly improbable that the remarkable extreme weather events of 2010 and 2011 could have all happened in such a short period of time without some powerful climate-altering force at work. The best science we have right now maintains that human-caused emissions of heat-trapping gases like CO2 are the most likely cause of such a climate-altering force." I just do not agree with his conclusion or that the weather is becoming more extreme. I am looking at various historical information of weather and climate events to determine if his statement is correct. That we are entering extreme times. I sent a report of droughts in the Northern Hemisphere for the last 1000 years and put a challenge to you. Look at the graphs provided and explain to me how they show droughts are getting worse either in frequency of events, duration of such events, or intensity of such events. The graphs have length of time per drought cycle and the intensity and the frequency of each cycle as well. I can not see an increase in droughts in North America from the graphs I look at, maybe you can. That is what I am asking for. On the fires, it is not about the cause of the individual fires. I posted that as demonstrating that the patterns are not more extreme. Points to get across. I am not against taking action and finding alternate fuels, I think it is a very good idea. So I am not against the general consensus of this website (which I believe most are advocating). I am questioning the whole concept of weather getting worse. Maybe a climate model predicts such events, that is about as good as a weather model forcasting weather. They are good for a few days and then it is anybody's guess. I am asking the posters to come up with conclusive empirical data that supports the thesis that Global Warming is definately leading to more severe weather (as defined by one of the following, intensity, frequency and duration). The best posted so far is the Munich Re disaster trend. And this is an indirect proxy with too many other varialble to create a conclusive argument of the overall thesis.
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  48. Norman #142 and #147, you seem to be looking only for 13's on the climate dice. Even if they haven't happened (and Russia and Pakistan must've been close to 13's), there's an awful lot of 11's and 12's being rolled together in close proximity. Scanning the archives for widely-scattered individual events in scattered localities and disparate times does not capture the remarkable concentrated nature of what we have seen in the past few years. I also do not trust your assertion that in Jeff Masters' precipitation chart you "... do not see any noticeable or certain upward trend in his graph." Well, I do. It just so happens that before about 1950 nearly all years were below average. Most years after 1950 were above average, and there is an upward trend, which is quite noticeable.
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  49. Norman @144:
    "My strongest objection is it is an indirect proxy for measuring actual weather extremes."
    (My emphasis) Norman @140:
    "Does the evidence really show this? Here is a report on British Columbia long term climate... There were some very big fires in the past. British Columbia drought history.
    (My emphasis) From Norman's source:
    "High-resolution charcoal analysis of lake sediments and stand-age information were used to reconstruct a 1000-year Ž fire history around Dog Lake, which is located in the montane spruce zone of southeastern British Columbia. Macroscopic charcoal (>125 mm) accumulation rates (CHAR) from lake sediment were compared with a modern stand-origin map and fire-scar dates in the Kootenay Valley to determine the relative area and proximity of Ž fires recorded as CHAR peaks. Small fires close to the lake and larger more distant fires appear as similar-sized peaks in the record. This information reinforces previous Ž findings where CHAR peaks represent a complex spatial aggregation of local to extra-local fires around a lake site."
    So to be absolutely clear, Norman has strong objections to using indirect proxies ..., unless he thinks they show what he wants them to show, in which case they are fine despite such confounding factors as an inability to distinguish between small, close fires and large, distant fires, or the effects of modern fire fighting on fires. Of course, the paper does not show what he thinks it shows. On the contrary, it shows "frequent stand-destroying fires" in the MWP, the last time NH temperatures were similar to modern values.
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  50. Norman @147, it would help your credibility no end if you would at least start drawing a distinction between North America and the Northern Hemisphere.
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