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2015 SkS Weekly News Roundup #15B

Posted on 11 April 2015 by John Hartz

California's new era of heat destroys all previous records

The California heat of the past 12 months is like nothing ever seen in records going back to 1895. The 12 months before that were similarly without precedent. And the 12 months before that? A freakishly hot year, too. 

What's happening in California right now is shattering modern temperature measurements—as well as tree-ring records that stretch back more than 1,000 years. It's no longer just a record-hot month or a record-hot year that California faces. It's a stack of broken records leading to the worst drought that's ever beset the Golden State.  

The chart below shows average temperatures for the 12 months through March 31, for each year going back to 1895. The orange line shows the trend rising roughly 0.2 degrees Fahrenheit per decade, just a bit faster than the warming trend observed worldwide.

 California Avg. Annual Temps: 1900-2014

12-Month Average Temperature (°F), April-March. Source: NOAA / Bloomberg

California's New Era of Heat Destroys All Previous Records by Tom Randall, Bloomberg, Apr 10, 2015

If we dig out all our fossil fuels, here’s how hot we can expect it to get

World leaders are once again racing to avert disastrous levels of global warming through limits on greenhouse gas emissions. An agreement may be in reach, but because of the vast supplies of inexpensive fossil fuels, protecting the world from climate change requires the even more difficult task of disrupting today’s energy markets.

The White House last month released a blueprint to reduce United States emissions by as much as 28 percent by 2025. The plan lays the groundwork for the formal international climate talks this December in Paris, where the goal is a treaty on emissions that will seek to limit the rise in global temperatures to 3.6 degrees Fahrenheit above preindustrial levels. Beyond 3.6 degrees, scientists say, the most catastrophic climate consequences will occur, possibly including the melting of the Greenland ice sheet.

Forging a treaty in Paris would be no small task, yet would be just the beginning of a solution. The greater challenge will be deciding how much of the world’s abundant supply of fossil fuels we simply let lie. (Bill McKibben and more recently The Guardian have taken a maximal position in their Leave It in the Ground campaign.)

If We Dig Out All Our Fossil Fuels, Here’s How Hot We Can Expect It to Get by Michael Greenstone, The Upshot, News York Times, Apr 8, 2015

New paper shows how sensitive the ocean biosystem is to climate change

Changes to the climate have had major impacts on the oceans and the biological systems that live there. A new study sheds more light on how fast these systems respond to changes. What the authors find is that short term climate changes can require 1,000 years for recovery. This means the current harm caused to the deep oceans by the changing climate will last for many centuries to come.

The new study, published in the Proceedings of the National Academy of Sciences by Dr. Sarah Moffitt and her colleagues is novel for a number of reasons. The researchers took core samples from ocean floor regions off the coast of California. The location was chosen in part because of the exceptional synchrony between sediment archives from offshore California and ice core records from the Greenland Ice sheet.

The authors’ method was novel because they sampled many different types of creatures, not merely the single-celled organisms that are most commonly studied. In fact, the authors included Mollusca, Echinodermata, Arthropods, and Annelida samples (approximately 5,000 fossils). There was major “turnover” in these animals with only small changes to oxygen levels.

New paper shows how sensitive the ocean biosystem is to climate change by John Abraham, Climate Consensus - The 97%, The Guardian, Apr 10, 2015

Obama adviser during Recession is given new challenge: climate change

Brian Deese’s first job at the White House included churning out economic doomsday scenarios, like how many communities might see unemployment rates hit 25 percent in the event of cascading bankruptcies across the Midwest.

“It was so harrowing,” Mr. Deese recalled of the grim months of recession in the earliest days of President Obama’s first term, when as a 31-year-old Yale Law School student he played a central role on the White House team that executed an $85 billion government bailout of Chrysler and General Motors.

These days the crisis atmosphere is gone and unemployment is at 5.5 percent, but Mr. Deese is still running the economic numbers at the White House on a different kind of crisis that is preoccupying the president. Mr. Deese’s job as Mr. Obama’s senior adviser in charge of climate policy is to push the president’s ambitious environmental agenda to governors, industry executives and international negotiators — while under daily political attacks from Congress and the coal industry.

Obama Adviser During Recession Is Given New Challenge: Climate Change by Coral Davenport & Julie Hirschfeld Davis, New York Times, Apr 9, 2015

Oceans facing carbon rates which spurred mass die-off 250 million years ago

In case you weren't already worried about the current and rapid acidification of the world's oceans, a new report by leading scientists finds that this very phenomenon is to blame for the worst mass extinction event the planet earth has ever seen—approximately 252 million years ago.

The findings, published this week in the journal Science by University of Edinburgh researchers, raise serious concerns about the implications of present-day acidification, driven by human-made climate change.

"Scientists have long suspected that an ocean acidification event occurred during the greatest mass extinction of all time, but direct evidence has been lacking until now," said lead author Dr. Matthew Clarkson in a statement. "This is a worrying finding, considering that we can already see an increase in ocean acidity today that is the result of human carbon emissions."

Oceans Facing Carbon Rates Which Spurred Mass Die-Off 250 Million Years Ago by Sarah Lazare, Common Dreams, Apr 10, 2015

Rapid global warming may be coming sooner than you think

A new study bolsters the case that a period of much faster global warming may be imminent, if not already beginning. The study, published Wednesday in Geophysical Research Letters, uses climate records gleaned from coral reefs in the South Pacific to recreate sea surface temperatures and ocean heat content dating back to 1791. The corals examined were from Fiji, Tonga and Rarotonga.

Information from the coral reef core samples reveals how ocean surface temperatures have varied over time in the South Pacific, along with how the uptake and release of upper ocean heat content has varied over time, as well. The insights they provide, together with other recent research, carry important implications for how global warming may play out during the next two decades or so.

The news that the coral reef core samples (combined with other climate signals) bring is not good, either.

Rapid global warming may be coming sooner than you think by Andrew Freedman, MAshable, Apr 9, 2015

The pope as messenger: making climate change a moral issue

This summer, Pope Francis plans to release an encyclical letter in which he will address environmental issues, and very likely climate change.

His statement will have a profound impact on the public debate. For one, it will elevate the spiritual, moral and religious dimensions of the issue. Calling on people to protect the global climate because it is sacred, both for its own God-given value and for the life and dignity of all humankind, not just the affluent few, will create far more personal commitment than a government call for action on economic grounds or an activist’s call on environmental grounds.

Making a case on theological grounds builds on long-standing arguments in the Catholic catechism that environmental degradation is a violation of the seventh commandment (Thou shalt not steal) as it involves theft from future generations and the poor. Against such a moral backdrop, the very call to “make the business case to protect the global climate” – a common tactic to argue for action on climate change – seems rather absurd. The pope’s statement will shift the tenor of the public and political conversation in needed ways.

The pope as messenger: making climate change a moral issue by Andy Hoffman & Jenna White, The Conversation, Apr 10, 2015 

The power and limits of Pope Francis’s climate change campaign

I encourage you to read “The pope as messenger: making climate change a moral issue,” an essay on The Conversation website by Andy Hoffman, director of the Erb Institute at the University of Michigan, and Jenna White, a graduate student studying the role of religious institutions in shaping humanity’s response to global warming. (The Erb Institute pursues “a sustainable world through the power of business.”)

The Power and Limits of Pope Francis’s Climate Change Campaign by Andrew Revkin, Dot Earth, New York Times, Apr 10. 2015

Western Canada’s glaciers could shrink by as much as 95% by 2100

The Canadian Rockies, which sit as a backdrop to many a stunning vista, could be almost entirely devoid of glaciers by the end of the century, a new study suggests.

Researchers modelled the impact of rising temperatures on glaciers across western Canada.

The results show widespread ice loss by 2050, and ice all but vanishing a few decades later. 

Western Canada’s glaciers could shrink by as much as 95% by 2100, study finds by Robert McSweeney, The Carbon Brief, Apr 6, 2015

Why people continue to deny climate change

Barack Obama famously said that “we don’t have time for  a meeting with the flat earth society”, and it’s good to know that the most powerful man in the world has both a sense of humour and a head that’s firmly screwed on. However, our perception of the curvature of our planet isn’t quite as potentially life threatening as the belief that we can continue to pump carbon dioxide into our atmosphere without consequence.

Science denial has always been a dangerous thing, from the persecution of Galileo to the belief that HIV doesn’t cause AIDS, the potential for widespread death makes this an important issue. In that regard there are no issues quite as important as climate change, the effects of which are already becoming evident. Irregular and extreme weather patterns have the potential to kill hundreds of millions of innocent men, women and children, and I find it incredibly alarming that people are happy to settle this issue on rhetoric alone.

Why People Continue to Deny Climate Change by Stefan Rollnick, The Secularist Convesation, Apr 7, 2015

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Comments 1 to 7:

  1. Here's a funny thought: if I was to use fake skeptic methods with the NOAA chart of California's temps, I would cherry-pick 1949 as starting point and calculate the "trend" to the present...

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  2. @ PC

    Ah, you have unerringly spotted the fingerprint of the 66 year cycle, which proves that it was the PDO "wot dunnit".

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  3. Although the Bloomberg California heat chart does not appear in the tech paper, at least with respect to the unprecedented nature of the current drought, the Bloomberg article appears to going off of:

    ... the 2012–2014 drought stands out in the context of the last millennium. In terms of cumulative severity, it is the worst drought on record (−14.55 cumulative PDSI),more extreme than longer (4 to 9 year) droughts. Considering only drought episodes defined by at least three consecutive years all lower than −2 PDSI, only three such events occur in the last 1200 years, and 2012–2014 is the most severe of these."

    Open Access: Griffin, Daniel, and Kevin J. Anchukaitis. "How unusual is the 2012–2014 California drought?." Geophysical Research Letters (2014). The tech article makes clear that the reduced precipitation is by no means unprecedented, but over the past three years the higher temperatures have resulted in higher rates of evaporation that have amplified the drought such that cummulative drought severity has been unprecedented.

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  4. The completely rational story for the California drought is that worse droughts have occurred in the deep past and are possible in the future, but a warming climate will make a recurrence of similar circumstances worse in the future. Bit of a mouthful, I know.

    When used in the context of the drought I find it unhelpful to see headlines like "California's new era of heat destroys all previous records". 

    Denial arguments play on the science papers that show worse droughts have occurred in the past.  When science based articles appear to sidestep and not acknowledge that, it appears that the science is being deceptive.  Doesn't help.

    But this is mainstream media.  I guess the upside is that usual media hyperbole is beginning to come down on the pro AGW side.

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  5. mjp, the article clearly states;

    "California has seen droughts before with less rainfall..."

    How does that constitute 'sidestepping' the severity of past droughts?

    You cite the headline, but it doesn't say anything about precipitation or 'drought' in general. It says that heat records have been broken. Which is true.

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  6.  "... usual media hyperbole is beginning to come down on the pro AGW side"

    I do love the term "pro AGW", as if it is something that many people would actually want to see happening. In common with many people, I think there is a causative relationship between ozone depletion and melanoma incidence rate. That doesn't mean I'm "pro CFCs", or that I'm "anti the Montreal Protocol".

    Terms such as "pro democracy" or "pro equal rights" do tend to convey the correct impression, but "pro AGW", I rather think not. 

    If you are genuinely concerned about perceived press bias, it might be educational for you to have a look at the article John Mason wrote a few weeks ago concerning the reporting of certain climate/weather related events. 

    cheers   bill f

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    Moderator Response:

    [JH] "Pro AGW" is typically shorthand for "pro AGW science".

    I also presume that your admonition is directed to the journalist who wrote the article. If so, you should post your concerns on the comment thread of the article as posted on the Los Angeles Times website.  

  7. It is disquieting that while the NSISC reports figures like 14.54 square miles of ice - 4 significant figures - , Cryosat2 reports figures like 21000 cubic km of ice.  What is happening with their satellite or their soft ware or with whoever is processing the data. By now we should have had three or so years of a graph for ice volume similar to the one that the NSIDC gives for ice extent and it should be to more significant figures.  Even if the measurement is off, if it is off by a certain amount in a certain direction, we would have a trend which is arguably more important than the absolute value.  Cryosat is said to be able to see through clouds so it should be able to give very good results during freeze and melting periods, clear and stomy weather and in summer and in winter.  What is going on at the ESA.

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