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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?

 


How did the UK grid respond to losing a few nuclear reactors?

Posted on 30 September 2014 by Guest Author

This is a re-post from PassiiviIdentiteetti, written by Jani-Petri Martikainen.

Answer: mainly by increasing the use of coal in power production.

In the second week of August power company EDF decided to shutdown their reactors in Heysham and Hartlepool. This was a precautionary measure after finding a defect in the boiler of Heysham unit 1. In total 4 reactors that can produce up to 2.6 GigaWatts (GW) of electricity were turned off. On the week they were turned off, the UK used an average of 30 GW.

Some were quick to declare that wind power came to the rescue when nuclear power was proven unreliable (for example Ari Phillips in Thinkprogress, Greenpeace, Giles Parkinson in reneweconomy.com.au...). More recently Justin McKeating from Greenpeace repeated the claim: "...we see a reversal of the view that renewables need to be supported by nuclear power. Although nuclear and wind power do not have the same generation characteristics, nuclear reactors now needing to lean on renewables means the nuclear industry has a big problem." Given that the claim appears unlikely on meteorological grounds and no evidence for it was provided, I felt a more careful scrutiny was called for.

So, did wind power replace missing nuclear capacity? Short answer is, no it did not. Missing nuclear generation was mostly replaced by increasing use of coal.

In Figure 1 I show the output of relevant power sources in the UK between Saturday 8th August and Thursday 14th August. EDF reactors were ramped down during this period and this can be clearly seen in the figure. Equally clear is that when nuclear output was declining, wind power output was declining even more steeply. So rather than coming to the rescue, wind power was unfortunately galloping away when the action started. The reduction in the amount of wind and nuclear power was mirrored by a clear increase in gas and coal power. Contrary to earlier claims, low carbon sources were replaced by fossil fuels.

Fig 1: UK power production during the reactor shutdowns.

Fig 1: UK power production during the reactor shutdowns.

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6 comments


People's Climate March NYC photos

Posted on 29 September 2014 by howardlee

There's no way around it. The People's Climate March in NYC on 9/21/2014 was massive! It was the largest climate march in history

Drone footage of the NYC march staging area (Youtube)

The river of humanity that flooded through the streets of Manhattan on Sunday sounded the alarm on climate change for politicians in the US and across the world to heed. Organizers estimate that more than 400,000 people marched in New York, well over triple estimates made just a couple of days before. The NYC march was just one of many climate change protests across 166 countries as a coordinated message to world leaders ahead of the UN summit on climate change

The event was covered by mainstream media, so what follows are a few anecdotes and photos from my personal experience on the march.

 Peter Yarrow at the People's Climate March

Peter Yarrow (of Peter Paul and Mary fame, co-writer of "Puff the Magic Dragon") entertains families organized by Moms Clean Air Force and Climate Parents, and other family-oriented groups.

  It's our future!

It's our future!

I knew it would be big when well over half the people on our packed double-decker train into the city were wearing climate t-shirts or carrying placards. But it was only afterwards, when I saw aerial footage of block after block after block of protesters, that I realized the scale of the phenomenon. Perhaps this is the turning point. Perhaps the human race might just get its act together in time to prevent the worst-case scenarios of climate change. 

It was a happy but determined crowd who began to coalesce at about 9:30 AM in a staging area that stretched 27 Manhattan blocks! Around us were protesters from Boston, Pennsylvania, Virginia, New Jersey, Minnesota, Manchester, and of course NYC. They were all ages, from babies to grannies in wheelchairs. They brought gongs and whistles and drums and guitars, ukuleles and vuvuzelas and saxophones.

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1 comments


2014 SkS Weekly Digest #39

Posted on 28 September 2014 by John Hartz

SkS Highlights

Dana's The Wall Street Journal downplays global warming risks once again received the most comments of the articles posted on SkS during the past week. Attracting the second highest number of comments was the repost of Roz Piscock's Carbon Brief article, Your questions on climate sensitivity answered

Toon of the Week

 2014 Toon 39

h/t to I Heart Climate Scientists

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6 comments


2014 SkS Weekly News Roundup #39B

Posted on 27 September 2014 by John Hartz

5 big announcements for cities at Climate Week 

Even as nations gathered in New York this week to discuss global-level action on climate change, there was strong recognition that cities, not countries, have so far played the pivotal role in the world's fight against climate change—and will continue to do so in the decades to come.

Urban centers house 54 percent of the world's population and account for approximately 75 percent of global greenhouse gas emissions. But they are also where most of the most innovative emission reduction strategies and adaptation measures are being implemented. These programs, as well as the question what needs to be done to further this work, were the topic of events throughout Climate Week New York City, from the United Nations to hotel conference rooms to the Empire State Building.

5 Big Announcements For Cities at Climate Week by Katherine Bagley, Inside Climate News, Sep 26. 2014

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0 comments


Your questions on climate sensitivity answered

Posted on 26 September 2014 by Guest Author

This is a re-post from Roz Pidcock at Carbon Brief

How sensitive is the earth to carbon dioxide? It's a question that's at the heart of climate science.

It's also complicated, and scientists have been grappling with pinning down the exact number for a while now.

But while the exact value of climate sensitivity presents a fascinating and important scientific question, it has little relevance for climate policy while greenhouse emissions stay as high as they are.

Nevertheless, each time a new research paper comes out suggesting climate sensitivity might be low it's misused by parts of the media to argue cutting emissions aren't so urgent after all.

The latest example comes in an article in today's Times, which claims a new climate sensitivity means "Climate change could be slower than forecast".

So what is climate sensitivity? What does and doesn't it tell us about future warming?

               Times Climate Sensitivity

Source: The Times, 26th September 2014

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20 comments


Citizen scientists classify storms for the Cyclone Center

Posted on 25 September 2014 by John Abraham

Taking measurements of the Earth’s weather and climatic state is challenging in many ways. One challenge is that we just don’t have sensors everywhere all the time. Sometimes we can use automated sensors (like Argo ocean floats or satellite imagery). But other times, scientists have to put their boots on, fire up a vehicle, and get out in the world. One great example is with hurricanes/cyclones. The best measurements of cyclone strength come from flights of airplanes through the storm itself.

It is a problem, however, when you just don’t have airplanes available for many cyclones. This problem is particularly an issue outside of the North Atlantic. Without airplanes, how do we know where cyclones are? How do we know how strong they are?

Identifying long-term trends is even more difficult because measurements change over the years. For instance, during the 1940s, aircraft observations of cyclones were routinely made in the North Atlantic and Pacific. In 1987, the Pacific observations halted and have not yet restarted. Without continued observations, how do we know if cyclones are changing in intensity or strength?

Cyclone Gilbert, September 14, 1988 top-of-cloud temperatures Cyclone Gilbert, September 14, 1988 top-of-cloud temperatures.

One way to get around the paucity of aircraft observations is through remote sensing from satellites. Satellites can take pictures (visual and other images) and record other data which can be used to infer cyclone intensity and position. The question is, how are the cyclone qualities inferred?

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0 comments


97 Hours of Consensus reaches millions

Posted on 24 September 2014 by John Cook

On 9/7, Skeptical Science launched 97 Hours of Consensus. Every hour for 97 consecutive hours, we published a quote from a climate scientist, as well as a hand-drawn caricature of the scientist. We had a simple goal: communicate in a playful fashion the overwhelming scientific consensus that humans are causing global warming.

Now that the dust has settled, we've had a chance to analyse how the campaign went. The result exceeded our expectations. Millions of people were exposed to the 97 quotes and caricatures of climate scientists!

Tweets from our twitter account @skepticscience were retweeted by many, being seen potentially 1.1 million times. The graph below shows the number of "impressions" of our tweets, meaning the potential number of times that our followers or followers of retweeters were exposed to our tweets.

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5 comments


2014 SkS Weekly News Roundup #39A

Posted on 23 September 2014 by John Hartz

Climate change as a catalyst of conflict

A respected military advisory board, with highly ranked retired officers from all branches of the armed forces, evaluated the effects of climate change on national security. They found that climate change is becoming a catalyst for conflict.

Climate change as a catalyst of conflict by Bud Ward and ChavoBart Digital Media., Yale Climate Connections, Sep 22, 2014

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1 comments


The Perplexing PETM

Posted on 23 September 2014 by howardlee

The Paleocene-Eocene Thermal Maximum (PETM) around 56 million years ago is perhaps the most studied of the many episodes of global warming in the geological record, but it still has plenty of puzzles. Professor Daniela Schmidt has written an article in "Geology" highlighting a couple of them, which is an excuse to delve a little into this episode of climate change that has some similarities to, and some important differences from, modern climate change.

 

The world in the Eocene, 50 million years ago

A different world 50 million years ago: Eocene globe with locations discussed in this post highlighted in yellow. Paleogeography globes © Ron Blakey, cpgeosystems.com

Rapid change and environmental turmoil

At the onset of the PETM, oceans acidified in less than 10,000 years (a geological blink) by around 0.3pH units as average surface ocean temperatures across the planet rose by 4° to 5°C (7-9°F), with the subsurface oceans warming by 5-6°C (9-11°F).  Ecosystems across the world were plunged into turmoil, with poleward migrations, decline of reefs, extinctions of some sea-bottom-living creatures, and in some places 20% of land plants went extinct while plant diversity dropped by more than a third. In mammals the effects included strong natural selection for small body size, and high species turnover, though there was no vertebrate mass extinction. Globally the resulting climate of the early Eocene was up to 15°C (27°F) warmer than today, supporting lush vegetation on Antarctica and the Arctic.

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2 comments


The Wall Street Journal downplays global warming risks once again

Posted on 22 September 2014 by dana1981

As has become the norm for media outlets owned by Rupert Murdoch, just before a half million people participated in the People’s Climate March around the world, The Wall Street Journal published an opinion piece downplaying the risks and threats posed by human-caused global warming. The editorial was written by Steven Koonin, a respected computational physicist who claims to have engaged in “Detailed technical discussions during the past year with leading climate scientists,” but who is himself not a climate scientist.

Koonin did admit that the climate is changing and humans are largely responsible, and noted,

There is well-justified prudence in accelerating the development of low-emissions technologies and in cost-effective energy-efficiency measures.

This is a step in the right direction. Unfortunately, Koonin’s editorial focused almost exclusively on the remaining uncertainties in climate science. Ironically, he stated,

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42 comments


Upcoming MOOC makes sense of climate science denial

Posted on 21 September 2014 by John Cook

In collaboration with The University of Queensland, Skeptical Science is developing a MOOC, or Massive Online Open Course, that makes sense of climate science denial. The Denial101x MOOC will launch in March 2015 on the EdX platform. Registration has just opened so you can now register for free. Here is a description of the MOOC:

 

Denial101x: Making Sense of Climate Science Denial

Climate change is real, so why the controversy and debate? Learn to make sense of the science and to respond to climate change denial.

About this Course

In public discussions, climate change is a highly controversial topic. However, in the scientific community, there is little controversy with 97% of climate scientists concluding humans are causing global warming.

  • Why the gap between the public and scientists?
  • What are the psychological and social drivers of the rejection of the scientific consensus?
  • How has climate denial influenced public perceptions and attitudes towards climate change?

This course examines the science of climate science denial.

We will look at the most common climate myths from “global warming stopped in 1998” to “global warming is caused by the sun” to “climate impacts are nothing to worry about.”

We’ll find out what lessons are to be learnt from past climate change as well as better understand how climate models predict future climate impacts. You’ll learn both the science of climate change and the techniques used to distort the science.

With every myth we debunk, you’ll learn the critical thinking needed to identify the fallacies associated with the myth. Finally, armed with all this knowledge, you’ll learn the psychology of misinformation. This will equip you to effectively respond to climate misinformation and debunk myths.

This isn’t just a climate MOOC; it’s a MOOC about how people think about climate change.

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1 comments


2014 SkS Weekly Digest #38

Posted on 21 September 2014 by John Hartz

People's Climate Mobilisation Poster by 350.org

"Today, we march... In Berlin, London, Amsterdam, Oslo, Rome, Stockholm, Paris, Madrid, Porto, Geneva, Ljubliana, Budapest and so many other places." - 350.0rg

SkS Highlights

As to be expected, Dana's The 97% v the 3% – just how much global warming are humans causing? garnered the most comments of the articles posted on Skeptical Science during the past week. Deciding who should pay to publish peer-reviewed scientific research by John Abraham attracted the second highest number of comments.

El Niño Watch

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4 comments


2014 SkS Weekly News Roundup #38B

Posted on 20 September 2014 by John Hartz

2014 on track to be hottest year on record

Just days after NASA data showed that August 2014 was the warmest August on record, the National Oceanic and Atmospheric Administration confirmed the ranking and raised the ante: There’s a good chance 2014 could become the warmest year on record.

“If we continue a consistent departure from average for the rest of 2014, we will edge out 2010 as the warmest year on record,” said Jake Crouch, a climatologist with NOAA’s National Climatic Data Center, during a press briefing Thursday.

Specifically, if each of the remaining months of the year ranks among the top five warmest, 2014 will take the top spot, he said.

2014 on Track to be Hottest Year on Record by Andrea Thomsposn, Climate Central, Sep 18, 2014

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9 comments


50 Canadian climate researchers speak out in support of the People's Climate March

Posted on 20 September 2014 by dana1981

The Canadian government is hell-bent on exploiting the Alberta tar sands to the fullest extent possible, even at the expense of the global climate. Canada simply cannot meet its carbon pollution reduction pledges if it continues to expand tar sands operations.

While the American government has finally begun to take the threat of climate change seriously and do something about it, the Canadian government has merely played lip service to the problem. 50 Canadian climate researchers have reached the point where they feel the need to speak out, using the People’s Climate March on September 21st as a catalyst to call for action. To that end, they penned the following letter.

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1 comments


Deciding who should pay to publish peer-reviewed scientific research

Posted on 18 September 2014 by John Abraham

There is an important discussion to be had about the future of scientific publications.

As a practicing and publishing scientist, I am judged by the quality and quantity of my contributions to the scientific community. Traditionally, this comes down to counting how many papers I publish and weighting them by the quality (impact) of the journals where the papers appear. A fancy word for this is “Impact Factor,” which is a measure of the frequency papers in a particular journal are cited compared to the number of pages a manuscript is.

The highest impact journals are often the hardest to get published in, sometimes having acceptance rates as low as 10%. Typical impact factors depend a lot on your field of study. In journals like Nature and Science, the impact factors are very high. In specialized journals and in specialized fields, the impact factors are much smaller.

In my native field of heat transfer, impact factors as high as 2.5 are rare. In climate science, flagship journals like the Journal of Geophysical Research and Geophysical Research Letters have impact factors in the 3–5 range – this means that the technical field of geophysics has a higher citation rate then say, heat and mass transfer. Journals such as Nature and Science, broad-category journals with huge readership, have citations rates of 42 and 31, respectively.

In this traditional model, universities pay each year (often thousands of dollars) to carry the journals. The universities then typically received both hard copy and e-copies of papers which faculty can then obtain. More recently, many library consortia have gone to an electronic-only system. It is probably obvious that with strengths of this system come weaknesses.

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17 comments


2014 SkS Weekly News Roundup #38A

Posted on 16 September 2014 by John Hartz

$1 Trillion: Annual investment goal puts climate solutions within reach

A two-year-old number is changing the way governments, companies and investors approach the fight against climate change: $1 trillion.

That is roughly the amount of additional investment needed worldwide each year for the next 36 years to stave off the worst effects of global warming and keep the Earth habitable, according to the International Energy Agency. The Paris-based organization of 29 developed countries calculated the cost in 2012 and raised its estimates this year. Ceres, a Boston-based nonprofit investor group that advocates environmental sustainability, framed it as the "Clean Trillion" in an investment campaign that has become a rallying cry.

While $1 trillion sounds like a lot, knowing the figure is good news, according to climate activists, investment experts and United Nations organizers of the next round of global climate talks. Worldwide, almost $4 trillion a year will need to be invested over that time anyway in electric grids, power plants and energy efficiency, the IEA says. In a global economy of $75 trillion, $1 trillion works out to 1.3 percent of the world's annual output of goods and services, or about $10,400 a person. The calculation also focuses the discussion on investment—suggesting the potential for returns and profits—rather than on costs for disaster response and losses to rising oceans.

Only $1 Trillion: Annual Investment Goal Puts Climate Solutions Within Reach by

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2 comments


Certain Arctic lakes store more greenhouse gases than they release

Posted on 16 September 2014 by Guest Author

This is a re-post of an NSF press release

New research, supported by the National Science Foundation (NSF), counters a widely-held scientific view that thawing permafrost uniformly accelerates atmospheric warming, indicating instead that certain Arctic lakes store more greenhouse gases than they emit into the atmosphere.

The study, published this week in the journal Nature, focuses on thermokarst lakes, which occur as permafrost thaws and creates surface depressions that fill with melted fresh water, converting what was previously frozen land into lakes.

The research suggests that Arctic thermokarst lakes are "net climate coolers" when observed over longer, millennial, time scales.

"Until now, we've only thought of thermokarst lakes as positive contributors to climate warming," said lead researcher Katey Walter Anthony, associate research professor at the University of Alaska Fairbanks Institute of Northern Engineering. "It is true that they do warm climate by strong methane emissions when they first form, but on a longer-term scale, they switch to become climate coolers because they ultimately soak up more carbon from the atmosphere than they ever release."

The researchers observed that roughly 5,000 years ago, thermokarst lakes in ice-rich regions of North Siberia and Alaska began cooling, instead of warming the atmosphere.

"While methane and carbon dioxide emissions following thaw lead to immediate radiative warming," the authors write, "carbon uptake in peat-rich sediments occurs over millennial time scales."

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The 97% v the 3% – just how much global warming are humans causing?

Posted on 15 September 2014 by dana1981

A pair of climate scientists recently had a dispute regarding how much global warming humans are responsible for. Gavin Schmidt from Nasa represented the consensus of 96–97% of climate experts in arguing that humans have been the dominant cause of global warming since 1950, while Judith Curry from Georgia Tech represented the opinions of 2–4% of climate experts that we could be responsible for less than half of that warming.

Curry is to be the featured speaker on this subject at a National Press Club event tomorrow hosted by the Marshall Institute; a right-wing thinktank that has spread misinformation about the dangers of smoking, ozone depletion, acid rain, DDT, and now climate change. She may also discuss the subject at an event next week hosted by the fossil fuel-funded right-wing think tank Texas Public Policy Foundation (TPPF).

The exchange between Schmidt and Curry can be read on RealClimate – a blog run by climate scientists. The discrepancy in both the quantity and quality of the supporting evidence used by each scientist was one of the most telling aspects of their debate.

For his part, Schmidt referenced the most recent IPCC report. The IPCC summarises the latest and greatest climate science research, so there is no better single source. The figure below from the IPCC report illustrates why 96–97% of climate science experts and peer-reviewed research agree that humans are the main cause of global warming.

The black bar indicates the amount of global surface warming observed from 1951 to 2010. The green bar shows the amount of warming caused by human greenhouse gas emissions during that time. The yellow is the influence from other human effects (mainly cooling from human sulfate aerosol emissions, which scatter sunlight), and the orange is the combined human effect. Below those are the contributions from external natural factors (mainly the sun and volcanoes) and from natural internal variability (mainly ocean cycles), while the whiskers show the uncertainty range for each.

IPCC AR5 Figure 10.5: Assessed likely ranges (whiskers) and their mid-points (bars) for attributable warming trends over the 1951–2010 period due to well-mixed greenhouse gases, other anthropogenic forcings (OA), natural forcings (NAT), combined anthropogenic forcings (ANT) and internal variability. The HadCRUT4 observations are shown in black with the 5 to 95% uncertainty range due to observational uncertainty in this record. IPCC AR5 figure 10.5: Likely ranges (whiskers) and their mid-points (bars) for attributable warming trends over the 1951–2010 period due to greenhouse gases, other anthropogenic forcings (OA), natural forcings (NAT), combined anthropogenic forcings (ANT) and internal variability. The HadCRUT4 observations are shown in black.

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109 comments


2014 SkS Weekly Digest #37

Posted on 14 September 2014 by John Hartz

SkS Highlights

97 hours of consensus: caricatures and quotes from 97 scientists by John Cook attracted the most comments of the articles posted on SkS during the past week. In addition, the 97 Hours campaign was widely acclaimed and promoted by numerous individuals and organizations throughout the world — see the SkS in theNews section of this Digest for details.

El Niño Watch

Long-term weather forecasters say it is now unlikely that a strong El Niño will develop this fall, dimming hopes in California for heavy rains that might bring relief from a severe drought.

In its latest monthly forecast, the federal Climate Prediction Center in College Park, Md., said that while there was still about a two in three chance that El Niño would develop, perhaps in the next two months, it would most likely be weak.

Hopes for a Strong El Niño Fade in California by Henry Fountain, New York Times, Sep 9, 2014

Toon of the Week

 2014 Toon 37

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1 comments


2014 SkS Weekly News Roundup #37B

Posted on 13 September 2014 by John Hartz

Agribusiness drives most illegal deforestation

Everyday products like beef, soy and palm oil already are widely blamed for spurring massive losses of the world's tropical forests. These products are also frequently linked to clearing that takes place in spite of local laws enacted to protect these forests.

But a new report from the environmental nonprofit Forest Trends for the first time attempts to quantify exactly how much of the world's illegal deforestation takes place to make way for palm oil plantations, cattle ranching, soy cultivation and other agricultural commodities.

The research team concluded that between 63 and 75 percent of global deforestation between 2000 to 2012 took place to make way for commercial agriculture. Of this, the authors found, 36 to 65 percent was illegal—the result of fraudulent licenses, destructive clearing techniques or other activities formally prohibited—but often overlooked—by local governments. Forest Trends estimates that the international trade of such products is worth an estimated $61 billion each year.

Agribusiness Drives Most Illegal Deforestation by Elizabeth Harball and Climate Wire/Scientific American, Sep 11, 2014

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