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Latest Posts


Explaining climate change science & rebutting global warming misinformation

Scientific skepticism is healthy. Scientists should always challenge themselves to improve their understanding. Yet this isn't what happens with climate change denial. Skeptics vigorously criticise any evidence that supports man-made global warming and yet embrace any argument, op-ed, blog or study that purports to refute global warming. This website gets skeptical about global warming skepticism. Do their arguments have any scientific basis? What does the peer reviewed scientific literature say?


Scientists to Explain 'Climate at Your Doorstep' at New Online Hub

Posted on 22 October 2014 by Guest Author

This is a re-post from Inside Climate News

While the climate community was fixed on global climate negotiations unfolding at the UN last week, one news organization was focused on educating people about the local damage that's already resulted from the world's inaction.

On Sept. 22, the online newsroom The Daily Climate launched a Kickstarter to raise $25,628 for "Climate at Your Doorstep." The project aims to build an online community of scientists, journalists and members of the public to discuss how climate impacts are already affecting people around the country and the world.

Organized around the hashtag #climatedoorstep, people will post questions, photos and observations on social media. The hash-tagged content will feed into a Daily Climate web page, and a panel of eight appointed scientific experts will respond to comments and questions.

The panelists include academic scientists, such as Katharine Hayhoe of Texas Tech University and Marshall Shepherd at the University of Georgia, and TV meteorologist Jim Gandy.



Another global warming contrarian paper found to be unrealistic and inaccurate

Posted on 21 October 2014 by John Abraham

It’s hard to find a reputable scientist who denies that human emissions of greenhouse gases are warming the planet and that there will be consequences for human society and the biological health of the planet. There are a few holdouts who, for various reasons, either think humans are not causing warming or that the warming will not have much consequence.

Some members of this vocal minority spend a lot of time trying to convince the public that they are right. They write letters to newspapers, appear in slick movies, give press conferences, promote their views to Congress, and so on. Their high profile gives the public a false sense that there are two relatively equal-sized bodies of experts that cannot agree on climate change; this is not true.

An even smaller subset also tries to publish their views in the scientific literature – the dueling ground for experts. Sometimes these contributions have been useful, adding some nuance to the discussion, but all too often they have proven to be of very poor quality when other scientists have had a chance to dissect them.

A few months ago, I co-authored an article which charted the different quality in scientific output from the Dwindling Few contrarians compared to the majority of experts. My colleague, Dana Nuccitelli, summarized the article here. What we show is that the Dwindling Few have had a very poor track record – having papers rebutted time after time after time because of errors they have made. The low quality of their research has caused journal editors resign, and they have wasted the time of their colleagues who have had to publish the rebuttals to their work.



From Pole to Pole - a climate-themed tour through a zoo

Posted on 20 October 2014 by BaerbelW

The Wilhelma is Stuttgart’s zoological and botanical garden and is one of the many participants in the Pole to Pole campaign organised by the European Association of Zoos and Aquaria (EAZA) which represents and links 345 institutions and organisations in 41 countries. The European zoos count millions of visitors each year and EAZA aims to educate as many of them as possible about environmental and conservation issues in countries around the world. Previous campaigns highlighted the plights of tigers, rhinosapes or European carnivores to name just a few examples. Participation of the zoos and what they offer in support of a campaign is voluntary and it usually hinges on whether or not a zoo keeps any of the flagship-species highlighted in a campaign.

EAZA-Logo WilhelmaLogoP2P-small



2014 SkS Weekly Digest #42

Posted on 19 October 2014 by John Hartz

SkS Highlights

Another "lightening rod" article by Dana, Dinner with global warming contrarians, disaster for dessert, drew the highest number of comments of the articles posted on SkS during the past week.

If you have not already done so, be sure to check out Rob Paining's original SkS article, Ocean Warming has been Greatly Underestimated. It's a real "eye opener".

Toon of the Week

2014 Toon 42

h/t to I Heart Climate Scientists



2014 SkS Weekly News Roundup #42B

Posted on 18 October 2014 by John Hartz

As deaths mount in Nepal disasters, questions about climate change raised

October is not typically the month for avalanches in Nepal. It is also not the time for blizzards. The fall month usually means clear skies and sunshine in the Himalayan country when thousands of foreigners climb its tall mountains.

Hikers were doing exactly that earlier this week when an avalanche and blizzard struck, killing at least 26 people, including four Canadians.

Still missing are 100 more trekkers. According to a Facebook page set up, there may be up to 32 Canadians whose family members have not been able to reach them since the avalanche struck.

As deaths mount in Nepal disasters, questions about climate change raised by Raveena Aulakh Environment and Allan Woods, Toronto Star, Oct 15, 2014



Why ice sheets will keep melting for centuries to come

Posted on 17 October 2014 by Guest Author

This article was originally published on The Conversation [UK] on Sep 26, 2014.

The Conservation Logo

Why ice sheets will keep melting for centuries to come

By Eelco Rohling, University of Southampton

Antarctic Ice Sheet

It may already be too late to stop Antarctic ice sliding into the ocean. EPA

Ice sheets respond slowly to changes in climate, because they are so massive that they themselves dominate the climate conditions over and around them. But once they start flowing faster towards the shore and melting into the ocean the process takes centuries to reverse. Ice sheets are nature’s freight trains: tough to start moving, even harder to stop.

We know this process has been going back and forth throughout history – it’s why we’ve had ice ages and warm periods. But until now we haven’t known exactly how quickly ice sheets retreated and reformed. New research published in the journal Nature Communications gives us an answer, and it isn’t great news.

It turns out sea levels often rose at scary rates in response to natural climate changes, long before mankind began pumping carbon into the atmosphere.

In the short-term sea level is affected by ocean warming and so-called “thermal expansion”, or melting glaciers based on land. These changes can occur quickly – within a decade – but their impact on sea level is relatively small, in the tens of centimetres. The drivers of longer-term sea level rise, over decades or centuries, are the continental ice sheets of Greenland and Antarctica.

On the fringes of these ice sheets are “ice shelves” stretching far out into the ocean. Ice shelves can be hundreds of meters thick and, because 90% of ice in water floats below the surface, they remain “grounded” on the sea floor as long as the sea is less deep than 90% of the ice shelf thickness. Where the sea floor is deeper or the ice shelf gets thinner, there will be an area of floating land ice; here, warming ocean water can get underneath and melt the ice. Once sufficiently destabilised, an ice shelf can break up catastrophically.

ice shelf

One small portion of the West Antarctic ice shelf slides into the sea. Images via NASA



2014 SkS Weekly News Roundup #42A

Posted on 16 October 2014 by John Hartz

15 years from now, our impact on regional sea level will be clear

Human activity is driving sea levels higher. Australia’s seas are likely to rise by around 70 centimetres by 2100 if nothing is done to combat climate change. But 2100 can seem a long way off.

At the moment, regional sea-level rise driven by warming oceans and melting ice is hidden by natural variability such as the El Niño, which causes year-to-year changes in sea level of several centimetres.

So at any particular place, the sea level might go up in one year, and down in the next. On Australia’s northwest coast, for example, the sea level was three centimetres below normal during 1998, but four centimetres above normal the following year.

At the same time, human-caused climate change is driving sea level relentlessly upwards in most regions, eventually pushing it far outside the bounds of historical variation. But when will the difference become clear?

15 years from now, our impact on regional sea level will be clear by John Church and Xuebin Zhang, The Conversation AU, Oct 12, 2014



Scientist in focus – Arctic adventurer Will Steger

Posted on 15 October 2014 by John Abraham

As readers know, I often focus on the story, and history, of someone who makes an impact in climate change. This is the third such article and I think you will agree, it shows that it isn’t just lab scientists and academics that are shaping the conversation about climate change.

Will Steger really rose to prominence as he led ventures to explore the polar regions of our planet. But those adventures were years in the making; they began in his childhood. Will was one of nine kids raised by parents who encouraged exploration. As long as Will stayed out of trouble and succeeded in school, he had very few limits placed on his activities. In 1957 when Will was 13, he would document meteorological activity in journals at night as part of the International Geophysical Year, in addition to nature drawings of close up flowers and other aspects of the natural world. By 15, he was inspired by adventures of Huck Finn and his National Geographic magazines to travel with his brother down the Mississippi River. It was his first (and last) motorized expedition.

In college, Will fell in love with geology and begin to explore the world more seriously. He graduated with a B.S. degree and began a teaching career which included climate change. But, it was in the wilderness that he began to make his mark.

It was Will’s early observation of the natural world and his curiosity of weather and climate that eventually enabled him to explore and survive in the Arctic. It is likely that no one has more first-hand experience in the Arctic and Antarctic than Will. He has traveled tens of thousands of miles by kayak and dogsled – leading teams on some of the most significant polar explorations our world has ever known. He was awarded the Lifetime Achievement Award from National Geographic Magazine, the inspiration from his childhood, in 2007.

Will Steger joined Amelia Earhart, Robert Peary and Roald Amundsen in receiving the National Geographic Society’s prestigious John Oliver La Gorce Medal in 1995 for Accomplishments in Geographic Exploration, Accomplishments in the Sciences, and Accomplishments in Public Service to Advance International Understanding. This was the first time the Society presented these three categories together and this award has not been given since.

Will Steger Will Steger

Among his accomplishments are the first confirmed dogsled journal to the North Pole without resupply (1986), the longest unsupported dogsled expedition in history (1600 mile traverse of Greenland in 1988), the first dogsled traverse of Antarctica (3471 miles in 1989-1990), and the first dogsled traverse of the Arctic Ocean in one season (1995).



Ocean Warming has been Greatly Underestimated

Posted on 14 October 2014 by Rob Painting

Key Points:
  • The oceans are by far the largest heat reservoir on Earth, absorbing 93% of global warming. Because of this, accurate assessments of heat uptake are essential to balance the sea level budget, and for observationally-based estimates of climate sensitivity.     
  • Prior to 2005, when the Argo global array of submersible floats became operational, ocean temperature was much more sparsely sampled, especially in the southern hemisphere, leading to larger uncertainty over the evolution of ocean warming through time.
  • Durack et al (2014) analyse the period from 1970-2004 combining ocean temperature and sea surface height measurements with climate model simulations, and find that sparse sampling in the southern hemisphere oceans, and limitations of previous analytical methods, has led to a substantial underestimate of warming in the 0-700 metre layer*.
  • When corrected for this bias, Durack (2014) find that the top 700 metre layer of ocean, over the period 1970-2004, has warmed some 24-58% more than previous analyses have indicated. 

Figure 1 - Observed (coloured bars) and modelled (grey bars) upper ocean heat content changes for the period 1970-2004 from previous analyses. Top coloured segments are the adjustments based on the Durack (2014) study. Units are x1022 joules 35 yr-1 and MMM = multi model mean. Image adapted from Durack et al (2014). 

The Oceans Have Warmed, But How Much?

The Argo system of automated floats was constructed in order to provide more reliable and robust measurements of ocean temperature, and other quantities such as salinity and current velocity. Although they only measure down to typical depths of 2000 metres, and still exclude regions such as the Arctic and Indonesian Throughflow, the 3000+ floats represent a major step up in accuracy over older methods.

Figure 2 - typical Argo cycle.



Dinner with global warming contrarians, disaster for dessert

Posted on 13 October 2014 by dana1981

Twelve climate scientists and contrarians recently had dinner together in the UK, which for some reason received media attention. While everyone should be free to have dinner with whomever they like, the problem with this particular event was that the ensuing media coverage made the contrarians seem downright reasonable. For example, the article about the dinner stated,

“...the insults slung around online only hinder the process of rational scientific debate.”

Yet one of the contrarians attending the dinner was Anthony Watts, who runs a blog that regularly insults climate scientists and climate realists. In fact, just a few days after the dinner, Watts was already taunting Ben Santer, one of the world’s most highly respected climate scientists, who had previously treated Watts with courtesy and respect. The article also quoted Watts as saying,

We’ve been at odds so long, it is time to present science together,

Climate contrarians are already free to present science at climate conferences. For example, the annual American Geophysical Union (AGU) fall meeting is the largest gathering of climate scientists presenting and discussing their research. Every year, the vast majority of scientific research presented at the AGU conference and others like it (about 97% or so) is consistent with the expert consensus on human-caused global warming. Contrarians don’t present science there because they have so little science to present.

The Mail on Sunday’s David Rose also attended the dinner. His latest climate article focused on the slight increase in Arctic sea ice as compared to the record low of two years ago (and of course on Al Gore), while ignoring the fact that the Arctic has lost about 70% of its total volume of sea ice over the past three decades.



2014 SkS Weekly Digest #41

Posted on 12 October 2014 by John Hartz

SkS Highlights

Howard Lee's original SkS article, The long hot tail of global warming - new thinking on the Eocene greenhouse climate, generated the most comments of the articles posted on SkS during the past week. 

El Niño Watch

"In their monthly update, scientists at the National Oceanic and Atmospheric Administration’s Climate Prediction Center and the International Research Institute for Climate and Society at Columbia University said there is still a two-thirds chance that a weak El Niño event emerges and that it will likely do so in the October-to-December timeframe, lasting until spring 2015."

Where Is El Nino? And Why Do We Care? by Andrea Thompson, Climate Central, Oct 9, 2014 

Toon of the Week


h/t to I Heart Climate Scientists



2014 SkS Weekly News Roundup #41B

Posted on 11 October 2014 by John Hartz

40% drop in solar PV cost is brightest spot of global epergy picture

In a world wrestling with climate change and the need to phase out fossil fuels, nothing is more critical than making sure there are reliable and cost-effective clean energy technologies ready to fill the void.

Keeping track of the pitfalls and possibilities is the Paris-basedInternational Energy Agency, an autonomous organization that has been analyzing energy for 40 years. In 2006, the influential agency began publishing Energy Technology Perspectives, a report that examines energy technologies and their potential for transforming the way the world uses power.

Because the agency is viewed as being above the fray of climate change politics, the ETP's detailed technology reports have become a must-read for policymakers and anyone else seeking guidance on what's possible and what's not in clean energy. The reports influence the UN climate treaty negotiations—talks meant to produce a climate accord in Paris late next year.

40% Drop in Solar PV Cost is Brightest Spot of Global Energy Picture by Elizabeth Douglass, InsideClimate News, Oct 10, 2014



What's the role of the deep ocean in global warming? Climate contrarians get this wrong

Posted on 10 October 2014 by Guest Author

This is a re-post from Greg Laden's Blog

What is the role of the ocean’s abyss in global warming?1

I’ve already posted on a study published in Nature Climate change that shows that the amount of extra global warming related heat in the Southern Oceans is greater than previously thought. There is another paper in the same journal by Llovel et al, “Deep-ocean contribution to sea level and energy budget not detectable over the past decade.” This paper verifies previous research that the oceans absorb a lot of the excess heat, but looks specifically at the ocean below 2,000 meters, which the paper referrs to in places as “deep” but that we should probably call “abyssal.”1 The paper concludes that the abyss is not warming. This is bad news, because if it was warming the total effects of global warming on the surface would be potentially less, or at least, stretched out over a longer period of time. But, it is not unexpected news. We already suspected that the abyssal ocean does not absorb much of the surface heat, while the shallower ocean absorbs quite a bit.

Research done prior to 2012 (e.g. Hansen et al 2011) parceled out the energy imbalance the Earth experiences from anthropogenic global warming. The extra heat caused by AGW from 2004 to 2010 was divided among the upper ocean (71%), the deeep ocean (5%), with the rest going various other places (only 4% over land). The new paper suggests that the abyssal ocean takes up closer to zero heat.

There are three complexities you need to be aware of to interpret this finding. First is the complexity in the climate system, second is the complexity of the research itself, and third is the relatively straight forward statistical problem of assigning meaning to specific numbers. That third one is important for journalists and regular people to pay attention to, because the climate science denial community is already exploiting it to misrepresent this study.



The long hot tail of global warming - new thinking on the Eocene greenhouse climate

Posted on 9 October 2014 by howardlee

Past climate changes like the Eocene Hyperthermals left many traces in the geological record. These tell scientists a great deal about what the Earth looked like in these hothouse eras, the changes they made to rainfall, drought, landscape, oceans, ecosystems and life. Ultimately those records contain clues to the causes of the climate changes, and are signposts to the effects we can expect from modern climate change.

A trio of new studies show that the Eocene Hyperthermals were the result of, not the cause of, global warming in the Eocene. This refocuses attention on abrupt global warming episodes like the PETM, and their role in converting the cooling Paleocene climate into the long-lived Eocene hothouse.

Modern climate change is even more abrupt, and is likely to have a similarly long, hot tail.

Hot flashes

The Paleocene and Eocene Hyperthermals were numerous recurring periods of hot global climate (a bit like human “hot flashes”) between around 59 and 34 million years ago. They were variations on a climate that was generally some 15°C (27°F) warmer than today, when the poles were free of ice even in winter and sea levels were about as high as they have ever been. The land was largely covered in jungle and even polar areas were lushly vegetated.



2014 SkS Weekly News Roundup #41A

Posted on 8 October 2014 by John Hartz

2014 extreme weather: Looking for climate ties

The ongoing, intense drought in California; the nonstop storms that left parts of Great Britain waterlogged all winter; the bitter winter cold in the eastern U.S. — these are just some of the extreme weather events from this year that could be examined in an annual report that looks for the fingerprints of climate change in such occurrences.

Bulletin of the American Meteorological Society since 2011, rounds up some of the most notable events from the previous year and tries to answer the question increasingly being asked: Did climate change cause this? Not only that, but it attempts to do so relatively quickly, (in the world of science, anyway) after the event, with the studies coming out in early October of the following year.

2014 Extreme Weather: Looking for Climate Ties, Climate Central, Oct 8, 2014 



GWPF funder Lord Leach – relying on unreliable sources of global warming information

Posted on 8 October 2014 by dana1981

DeSmog UK has found that libertarian banker Lord Leach is a likely funder of the anti-climate political advocacy group Global Warming Policy Foundation (GWPF). In May of 2009, Lord Leach gave a long speech in Parliament detailing his beliefs about global warming.

The speech was full of inaccuracies, myths, and misinformation. Known as a Gish Gallop, the sheer number of false claims in the speech would require tremendous effort to debunk. Most telling were the sources that Lord Leach relied upon to support his statements. For example,

Probably the best climatologist in the world is Professor Lindzen and another good one is Professor Singer.

While Richard Lindzen is a climate scientist, he’s also the climate scientist who’s been the wrongest, longest. Throughout his climate science career, Lindzen consistently took positions that were contrary to the climate science mainstream. For example, Lindzen claimed that global warming over the 20th century was minimal, that humans have an insignificant impact on global temperatures, and that water vapor will act to dampen global warming. All of these claims and many more have proven to be completely wrong. In another contrarian position, Lindzen has disputed the link between secondhand smoke and lung cancer.



Bart Verheggen Interview: Scientists’ Views About Attribution Of Global Warming

Posted on 7 October 2014 by CollinMaessen

This is a re-post from Real Sceptic

Very few Americans are aware of the overwhelming scientific consensus on global warming (Maibach 2013). There’s a huge gap between the agreement the public thinks there is between scientists and the actual agreement among scientists. It’s because of this lack of awareness that several studies investigated what the agreement is among scientists.

When researchers surveyed climate scientists on the cause of global warming 97% of the actively publishing climatologists said that “human activity is a significant contributing factor in changing mean global temperatures” (Doran 2009) Researchers found the same patterns when they analysed public statements of climate experts (Anderegg 2010). When researchers looked into how the scientific consensus on global warming evolved from 1996 to 2009 they found a steady increase in the agreement among scientists (Bray 2010). The latest survey on the scientific literature found that 97% “endorsed the consensus position that humans are causing global warming” (Cook 2013).

The consensus gap



Tackling global warming will improve health, save lives, and save money

Posted on 6 October 2014 by John Abraham

A very recent study released in JAMA (Climate Change: Challenges and Opportunities for Global Health) provides a very thorough review showing how climate change affects human health. Perhaps more importantly, the paper also describes how tackling climate change leads to many health and economic benefits.

Authors Jonathan Patz, Howard Frumkin and colleagues combined a survey of the current literature with measured and projected changes to climate to assess health risks associated with climate change. They report many things that we already know. For instance, some of the adverse health effects from climate change are heat-related (such as heat stress, increased cardiac arrests, reductions in work productivity, to name a few).

Others, such as decreased respiratory health (from changes to ground level pollution associated with climate change or increases in pollens for example), increases in infectious diseases, decreased food security, and more mental stress are just some of the lesser reported effects we are seeing and will continue to see. The authors conclude,

Evidence over the past 20 years indicates that climate change can be associated with adverse health outcomes. Health care professionals have an important role in understanding and communicating the related potential health concerns and the co-benefits from reducing greenhouse gas emissions.



2014 SkS Weekly Digest #40

Posted on 5 October 2014 by John Hartz

SkS Highlights

Nuclear power's role in mitigating manmade climate change and the willingness of Evangelical Christians to embrace the overwhelming body of scientific evidence of manmde climate change were the two hot topics on the comment threads of the articles posted on SkS during the past week. Garnering the highest number of comments was How did the UK grid respond to losing a few nuclear reactors?, a guest post by Jani-Petri Martikainen. Attracting the second highest number of comments was Dana's Global warming: a battle for evangelical Christian hearts and minds.

Toon of the Week

 2014 Toon 40

h/t to Climate Change Guide



2014 SkS Weekly News Roundup #40B

Posted on 4 October 2014 by John Hartz

A change in the climate

Less than two weeks have passed and yet it isn’t too early to say it: The People’s Climate March changed the social map — many maps, in fact, since hundreds of smaller marches took place in 162 countries. That march in New York City,spectacular as it may have been with its 400,000 participants, joyous as it was, moving as it was (slow-moving, actually, since it filled more than a mile’s worth of wide avenues and countless side streets), was no simple spectacle for a day. It represented the upwelling of something that matters so much more: a genuine global climate movement.

When I first heard the term “climate movement” a year ago, as a latecomer to this developing tale, I suspected the term was extravagant, a product of wishful thinking. I had, after all, seen a few movements in my time (and participated in several).  I knew something of what they felt like and looked like — and this, I felt, wasn’t it.

I knew, of course, that there were climate-related organizationsdemonstrations, projects, books, magazines, tweets, and for an amateur, I was reasonably well read on “the issues,” but I didn’t see, hear, or otherwise sense that intangible, polymorphous, transformative presence that adds up to a true, potentially society-changing movement.

It seemed clear enough then: I could go about most of my life without brushing up against it. Now, call me a convert, but it’s here; it’s big; it’s real; it matters.

A Change in the Climate by Todd Gitlin, The Huffington Post/, Oct 2, 2014



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