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Climate Hustle

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?

 


Climate scientists just debunked deniers' favorite argument

Posted on 28 June 2017 by dana1981

Whenever they hold one of their frequent hearings to reject and deny established climate science, congressional Republicans invariably trot out contrarian scientist John Christy, who disputes the accuracy of climate models. In doing so, Christy uses a cherry-picked, error riddled chart, but there’s a nugget of truth in his argument. Although the discrepancy isn’t nearly as large as Christy’s misleading chart suggests, atmospheric temperatures seem not to have warmed quite as fast since the turn of the century as climate model simulations anticipated they would.

santer figure

Remote Sensing Systems estimate of the temperature of the middle troposphere compared to the CMIP5 multi-model average (top frame), and the difference between the two over time (bottom frame). Illustration: Santer et al. (2017), Nature Geoscience

How you react to this information is a good test of whether you’re a skeptic or a denier. A denier will declare “aha, the models are wrong, therefore we don’t need any climate policies!” A skeptic will ask what’s causing the difference between the observational estimates and model simulations.

There are many possible explanations. Maybe the tricky and often-adjusted estimates of the atmospheric temperature made by instruments on orbiting satellites are biased. Maybe there’s something wrong with the models, or our understanding of Earth’s atmosphere. Maybe the inputs used in the model simulations are flawed. The answer is likely a combination of these possibilities, but in congressional testimony earlier this year, Christy tried to place the blame entirely on the models, with a denier-style framing:

the average of the models is considered to be untruthful in representing the recent decades of climate variation and change, and thus would be inappropriate for use in predicting future changes in the climate or for related policy decisions.

And in testimony to Congress in December 2015, Christy offered his unsupported speculation that the discrepancy was a result of climate models being too sensitive to rising greenhouse gases:

Read more...

9 comments


We are heading for the warmest climate in half a billion years

Posted on 27 June 2017 by Guest Author

The ConversationGavin Foster, Professor of Isotope Geochemistry, University of Southampton; Dana Royer, Professor of Earth and Environmental Sciences, Wesleyan University, and Dan Lunt, Professor of Climate Science, University of Bristol

This article was originally published on The Conversation. Read the original article.

Carbon dioxide concentrations are heading towards values not seen in the past 200m years. The sun has also been gradually getting stronger over time. Put together, these facts mean the climate may be heading towards warmth not seen in the past half a billion years.

A lot has happened on Earth since 500,000,000BC – continents, oceans and mountain ranges have come and gone, and complex life has evolved and moved from the oceans onto the land and into the air. Most of these changes occur on very long timescales of millions of years or more. However, over the past 150 years global temperatures have increased by about 1℃, ice caps and glaciers have retreated, polar sea-ice has melted, and sea levels have risen.

Some will point out that Earth’s climate has undergone similar changes before. So what’s the big deal?

Scientists can seek to understand past climates by looking at the evidence locked away in rocks, sediments and fossils. What this tells us is that yes, the climate has changed in the past, but the current speed of change is highly unusual. For instance, carbon dioxide hasn’t been added to the atmosphere as rapidly as today for at least the past 66m years.

In fact, if we continue on our current path and exploit all convention fossil fuels, then as well as the rate of CO₂ emissions, the absolute climate warming is also likely to be unprecedented in at least the past 420m years. That’s according to a new study we have published in Nature Communications.

Life in the planet’s last greenhouse period, the Eocene. Jay Matternes / Smithsonian Museum, CC BY

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3 comments


New study confirms the oceans are warming rapidly

Posted on 26 June 2017 by John Abraham

As humans put ever more heat-trapping gases into the atmosphere, the Earth heats up. These are the basics of global warming. But where does the heat go? How much extra heat is there? And how accurate are our measurements? These are questions that climate scientists ask. If we can answer these questions, it will better help us prepare for a future with a very different climate. It will also better help us predict what that future climate will be.

The most important measurement of global warming is in the oceans. In fact, “global warming” is really “ocean warming.” If you are going to measure the changing climate of the oceans, you need to have many sensors spread out across the globe that take measurements from the ocean surface to the very depths of the waters. Importantly, you need to have measurements that span decades so a long-term trend can be established. 

These difficulties are tackled by oceanographers, and a significant advancement was presented in a paper just published in the journal Climate Dynamics. That paper, which I was fortunate to be involved with, looked at three different ocean temperature measurements made by three different groups. We found that regardless of whose data was used or where the data was gathered, the oceans are warming.

OHC

Ocean heat content increase globally (top frame) and in four ocean basins (bottom frames). Illustration: Wang et al. (2017), Climate Dynamics

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2 comments


2017 SkS Weekly Climate Change & Global Warming Digest #25

Posted on 25 June 2017 by John Hartz

Story of the Week... Resolution of the Week... Toon of the Week... Quote of the Week... Graphic of the Week... SkS Spotlights... Video of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Postings... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

The World Is Burning

Aral Sea Muynak Uzebkistan Port 

A view of rusted, abandoned ships in Muynak, Uzebkistan, a former port city whose population has declined precipitously with the rapid recession of the Aral Sea. Credit: UN Photo/Eskinder Debebe

Record high temperatures are gripping much of the globe and more hot weather are to come. This implies more drought, more food insecurity, more famine and more massive human displacements.

In fact, extremely high May and June temperatures have broken records in parts of Europe, the Middle East, North Africa and the United States, the World Meteorological Organization (WMO) reported*, adding that the heat-waves have arrived unusually early.

At the same time, average global surface temperatures over land and sea are the second highest on record for the first five months of 2017, according to analyses by the US National Oceanic and Atmospheric Administration (NOAA), NASA-Goddard Institute for Space Studies and the European Centre for Medium Range Weather Forecasting Copernicus Climate Change Service.

The World Is Burning by IPS News Desk, Inter Press Service (IPS), June 23, 2017

*Records fall amid heatwaves, World Meterological Organization (WMO), June 21, 2017

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1 comments


2017 SkS Weekly Climate Change & Global Warming News Roundup #25

Posted on 24 June 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

From heatwaves to hurricanes, floods to famine: seven climate change hotspots

Global warming will not affect everyone equally. Here we look at seven key regions to see how each is tackling the consequences of climate change

Mapping Climate Hotspots

Mapping the world’s climate hot spots and identifying where the impacts will be the greatest is increasingly important for governments and those who need to prioritise resources. Photograph: Stephane Mahe/Reuters

It could have been the edge of the Sahara or even Death Valley, but it was the remains of a large orchard in the hills above the city of Murcia in southern Spain last year. The soil had broken down into fine white, lifeless sand, and a landscape of rock and dying orange and lemon trees stretched into the distance.

A long drought, the second in a few years, had devastated the harvest after city authorities had restricted water supplies and farmers were protesting in the street. It was a foretaste of what may happen if temperatures in the Mediterranean basin continue to rise and desertification grows.

All round the world, farmers, city authorities and scientists have observed changing patterns of rainfall, temperature rises and floods. Fifteen of the 16 hottest years have been recorded since 2000. Carbon dioxide and other greenhouse gas emissions steadily climb. Oceans are warming and glaciers, ice caps and sea ice are melting faster than expected. Meanwhile, heat and rainfall records tumble.

The evidence for the onset of climate change is compelling. But who and where is it hitting the hardest? How fast will it come to Africa, or the US? What will be its impact on tropical cities, forests or farming? On the poor, or the old? When it comes to details, much is uncertain.

From heatwaves to hurricanes, floods to famine: seven climate change hotspots by John Vidal, Guardian, June 23, 2017

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4 comments


Exxon, Stephen Hawking, greens, and Reagan’s advisors agree on a carbon tax

Posted on 23 June 2017 by dana1981

What do ExxonMobil, Stephen Hawking, the Nature Conservancy, and Ronald Reagan’s Secretary of Treasury and Chief of Staff have in common? All have signed on as founding members to the Climate Leadership Council, which has met with the White House to propose a revenue-neutral carbon tax policy.

The group started with impeccable conservative credentials, bringing on cabinet members from the last three Republican presidential administrations (Ronald Reagan, George HW Bush, and George W Bush): two former Secretaries of State, two former Secretaries of Treasury, and two former chairmen of the President’s Council of Economic Advisors. It was founded by Ted Halstead, who explained the group’s proposed policy in a TED talk:

Some of the world’s brightest scientific and economic minds have since become founding members, including Stephen HawkingSteven ChuMartin Feldstein, and Lawrence Summers. So have ExxonMobil, BP, and Shell. But it’s not just the oil industry joining the call for a carbon tax; GM, Proctor & Gamble, Pepsico, and Johnson & Johnson are among the major companies signing on. As have environmental groups like the Nature Conservancy.

Citizens’ Climate LobbyrepublicEn, the Niskanen Center, and the Weather Channel are among the Climate Leadership Council’s strategic partners.

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15 comments


Claiming that Listerine alleviates cold symptoms is false: To repeat or not to repeat the myth during debunking?

Posted on 22 June 2017 by Stephan Lewandowsky

With terms such as “post-truth” and “fake news” becoming increasingly prominent in the media and public discourse, the ability to effectively correct inaccurate information has never been more pertinent. Unfortunately, the task of correcting misinformation is far from trivial. In many instances, issuing corrections remains only partially effective and people often continue to rely on outdated information. This is known as the continued-influence effect

But this does not mean that debunking of misinformation is necessarily impossible: On the contrary, there are some known techniques that can help make a correction more effective, which John Cook and I summarized in the Debunking Handbook some time ago.

One recommendation in the Debunking Handbook is that it is best to avoid repeating the initial misconception while issuing a correction. This recommendation was based on data available at the time of writing, which suggested that the repetition of the misconception — even when it is corrected in the same sentence — increase its familiarity. For example, the statement “It is false to claim that Listerine alleviates cold symptoms” unavoidably strengthens the link between the two concepts, namely Listerine and alleviating colds, even though the statement seeks to correct that myth.

The potential problem that arises from repeating the myth to correct it is that people are more likely to think that familiar information is true. In consequence, correcting the myth may ironically strengthen its prominence in people’s minds, a phenomenon known as the familiarity backfire effect. 

Recent research, however, has not found a familiarity backfire effect under conditions where it was expected. In a nutshell, two articles published by colleagues and I (with Ullrich Ecker and Briony Swire, respectively, as lead authors) found evidence for familiarity-based processing but failed to find a familiarity backfire effect.

You can read more about this latest research in a series of three blog posts on Shaping Tomorrow's World:

What is the upshot of this latest research?

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9 comments


To lead on climate, leave the ivy tower

Posted on 21 June 2017 by Guest Author

America’s top universities expend considerable efforts to lead in the rankings, but last week they fell short—missing a critical opportunity to show moral leadership on climate change. If top schools want to lead on climate action, they should join the “We Are Still In” coalition, a collection of states, cities, businesses, and universities promising to support the Paris Climate Agreement.

President Trump’s decision to pull out of the international climate accord was swiftly rejected by local and state officials, as well as members of the business and academic community. Over 1,000 leaders have signed on to the “We Are Still In” pledge—including mayors and governors representing about 120 million people. More than 200 colleges and universities have joined. Leadership from these institutions sends a powerful message to President Trump and the globe: even if the federal government reneges on its international commitments, Americans are stepping up to fill the gap.

Unfortunately, our 11 academic institutions—the “Ivy-Plus” group—were not on that list (Columbia was the lone member of the Ivy-Plus group to sign both coalition statements). Instead, our universities—Brown, Cornell, Dartmouth, Duke, Georgetown, Harvard, Johns Hopkins, Massachusetts Institute of Technology, Stanford, University of Pennsylvania, and Yale—signed a separate statement of support. Even though we applaud this affirmation of commitment to climate change, this action misses the collective strength of participation in the “We Are Still In” coalition, and it lacks the leadership we expect from these institutions. Sometimes absence can even be more telling than presence.

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4 comments


New Video: John Cook and the 97 Percent

Posted on 20 June 2017 by greenman3610

This is a re-post from Climate Crocks 

Scientific conclusions derive from an understanding of basic laws supported by laboratory experiments, observations of nature, and mathematical and computer modeling. Like all human beings, scientists make mistakes, but the scientific process is designed to find and correct them. This process is inherently adversarial””scientists build reputations and gain recognition not only for supporting conventional wisdom, but even more so for demonstrating that the scientific consensus is wrong and that there is a better explanation. That’s what Galileo, Pasteur, Darwin, and Einstein did. But when some conclusions have been thoroughly and deeply tested, questioned, and examined, they gain the status of “well-established theories” and are often spoken of as “facts.

Climate Change and the Integrity of Science

“There’s no such thing as settled science” and “science does not work by consensus”, are things we commonly hear from people who really should know better.

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9 comments


Factcheck: Grenfell Tower fire and the Daily Mail’s ‘green targets’ claim

Posted on 19 June 2017 by Guest Author

This is a re-post from Leo Hickman at Carbon Brief

Three days after the devastating fire at Grenfell Tower in west London, much of the media coverage of the tragedy is now focusing on the possible causes.

A wide range of possible contributory factors has been cited – lack of sprinklers, lack of adequate fire escapes, no central fire alarms, etc. But there has been much speculation that the cladding, added to the building during a recent refurbishment, could have helped the fire to spread rapidly up the exterior of the building.

A number of newspapers have focused their investigations on possible cost-cutting during the renovation, as well as prior warnings by residents that safety standards were being ignored. For example, the Times today has a frontpage story highlighting that “contractors could have acquired the fire-resistant version [of the cladding used] for less than £5,000 extra”. The refurbishment of the building cost £8.6m.

However, the Daily Mail is making its own claim. On its frontpage it says there are “three lethal questions” that need answering; the first of which is: “Were green targets to blame for the fire tragedy?” It adds that “experts”, which the paper doesn’t name, are asking whether the cladding was “installed simply to meet environmental targets”.

On page eight is a full-page commentary from Ross Clark, sitting under the headline question: “So did an obsession with green targets lead to inferno?”

Clark, who has published various climate sceptic articles and written a book attacking regulations he believes to be “strangling” the UK, begins the article:

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16 comments


2017 SkS Weekly Climate Change & Global Warming Digest #24

Posted on 18 June 2017 by John Hartz

Story of the Week... Toon of the Week... Video of the Week... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

May Continues a Ridiculous Warm Streak for the Planet

Another month is in the global temperature record books. While May just missed setting a record, the data is another reminder that climate change is making the world hotter and pushing it into a new state.

This May was the second-warmest May on record, according to NASA data released on Thursday. The planet was 1.6°F (0.88°C) warmer than normal last month, trailing 2016 by just a 10th of a degree.

GISTEMP LOTI Anomaly May 2017 

This May was the second-hottest May on record. Credit: NASA GISS

Widespread hot spots stretched from pole to pole, showing no corner of the globe is untouched by the impact of rising carbon dioxide levels in the atmosphere. Temperatures soared up to 13.8°F (7.1°C) above normal in parts of Antarctica while a wide swath of heat cooked northern Africa and western Europe.

With May in the record books, NASA data also shows that this was the second-warmest spring on record, again trailing only 2016. NASA climate researcher Gavin Schmidt said the first five months of the year make it likely that this will be the second-hottest year on record trailing only, you guessed it, 2016.

Last year’s record heat got a boost from El Niño. The absence of El Niño this year in some ways makes the planetary heat even more shocking, though it certainly fits a pattern.

After all, May marked an all-time monthly peak for carbon dioxide levels in what’s become an annual rite of passage. Scientists found that carbon dioxide at Mauna Loa Observatory, the marquee measuring station, reached 409.65 parts per million (ppm) last month. That coupled with the second-hottest May on record are major markers of the current state of the world’s climate.

May Continues a Ridiculous Warm Streak for the Planet by Brian Kahn, Climate Central, June 15, 2017

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7 comments


2017 SkS Weekly Climate Change & Global Warming News Roundup #24

Posted on 17 June 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Warm Waters in West Antarctica 

A recent paper in Reviews of Geophysics describes the atmospheric and oceanic processes that are causing ice loss in the Antarctic.

Antarctica Thwaites glacier NASA

Thwaites Glacier flows out into the Amundsen Sea Embayment where it floats on the seawater. The underside is being melted by relatively warm water. Credit: NASA  

The vast Antarctic ice sheet contains about 30 million cubic kilometers of ice, which is 90% of the Earth’s freshwater ice. If it were all to melt, it would increase sea level by about 70 meters. Fortunately, surface temperatures across most of the continent stay well below freezing all year round so there is virtually no ice loss through surface melt. Instead, most of the ice loss is through iceberg calving and ocean-induced melting from the under-side of ice shelves.

One area that scientists are keeping a close eye on is the Amundsen Sea Embayment to the west of the Antarctic Peninsula. Here the ice is being melted from below by warm ocean waters at a greater rate than ice is added through snow accumulation, and this region is currently contributing about a tenth of current global sea level rise. A review article recently published in Reviews of Geophysics examined the complex atmospheric and oceanic factors that control the delivery of warm waters to the sub-ice region of West Antarctica and considered the potential for ice loss in the future. The editors asked two of the authors to give an overview of scientific research in this area. 

Warm Waters in West Antarctica by John Turner & Hilmar Gudmundsson, Eos.org, June 16, 2017 

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2 comments


Explainer: Dealing with the ‘loss and damage’ caused by climate change

Posted on 16 June 2017 by Guest Author

This is a re-post from Carbon Brief

Scaling down our emissions and building resilience against climate change can only take us so far. Some negative impacts and damages are now unavoidable. The inevitable consequences of human-caused climate change have collectively come to be known as “loss and damage”.

First emerging decades ago as a relatively obscure plea by small island states, loss and damage has now gained recognition as the third pillar of international climate policy, after mitigation and adaptation. But turning the concept of loss and damage into something more tangible for countries bearing the brunt of extreme weather or rising seas has proved more fractious.

As the latest UN climate change conference gets underway in Bonn, Germany, this week, Carbon Brief charts the journey of loss and damage through the international policy apparatus, and looks at the role that climate science (and scientists) can play in addressing it.

Climate risk

From contributing to shrinking the world’s glaciers to boosting flood risk in southern England, climate change is having discernible impacts across all continents and oceans.

While it’s hard to pin a dollar value on damages, economic models suggest climate change already costs hundreds of billions in damages globally during the 20th century through lost crops, rising seas and more extreme weather.

Looking ahead, the consequences will worsen as temperatures climb further. And with those facing the greatest risks often the least able to absorb the damage, climate change is expected to exacerbate economic inequalities and erode progress on reducing poverty.

The surest way to avoid future climate impacts is to reduce the greenhouse gas emissions that drive them – known as mitigation. But even with efforts to limit warming to “well below 2C” above pre-industrial times – the ambitious goal set out in the Paris Agreement – some climate impacts are unavoidable because of the warming already “baked” into the system.

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28 comments


SkS Analogy 8 - I'll take the specialist

Posted on 15 June 2017 by Evan

Tag Line

I’ll take the specialist, please.

Elevator Statement

Your child has an eye injury and needs a doctor. Who are you going to call?

A Ph.D. in chemistry? No, you need a medical doctor.
A family-practice medical doctor? No, you need an eye doctor.
Any eye doctor? No, you need an eye doctor who does surgery.
Any eye surgeon? No, an experienced eye surgeon.

Because this is your child’s eye, you decide to take your child to two, experienced eye surgeons to make sure they agree on the course of action. You want consensus from at least two recognized experts in their field of specialty before messing with something as precious as the eye of your child. You care about your child and are using common sense.

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22 comments


New research may resolve a climate ‘conundrum’ across the history of human civilization

Posted on 14 June 2017 by dana1981

Earth’s last ice age ended about 12,000 years ago. The warmer and more stable climate the followed allowed for the development of agriculture and the rise of human civilization. This important period encompassing the past 12,000 years is referred to as the Holocene geological epoch. It also created a “conundrum” for climate scientists, because global temperatures simulated by climate models didn’t match reconstructions from proxy data.

To be specific, the overall temperature change during the Holocene matched pretty well in reconstructions and models, but the pattern didn’t. The best proxy reconstruction from a 2013 paper led by Shaun Marcott estimated more warming than models from 12,000 to 7,000 years ago. Then over the past 7,000 years, Marcott’s reconstruction estimated about 0.5°C cooling while model simulations showed the planet warming by about the same amount.

A new paper led by Jonathan Baker may help to resolve that discrepancy. The scientists examined stalagmites from a cave in the southern Ural Mountains of Russia. The ratio of oxygen isotopes in the stalagmites can be used to estimate past winter temperatures. The Marcott study had one known shortcoming – the proxy temperature data they used mostly represented the summer season. And as Baker explained, changes in the Earth’s orbital cycles have caused summer cooling and winter warming during the Holocene:

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6 comments


The Trump Effect - Making Lemonade from Lemons

Posted on 13 June 2017 by BaerbelW

It may just be me but I get the distinct impression that - "thanks" to Donald Trump's ill-advised and shortsighted decision to withdraw the U.S. from the Paris agreement - people have been hearing a lot more about climate change since June 1.

As one datapoint, the topic got a lot of coverage on German TV on June 2 with for example about 8 out of 15 minutes dedicated to it in the main news at 8pm or 10 minutes out of 30 at 10pm. There has also been a lot of coverage in the international press as shown in this very helpful CarbonBrief analysis which lets you select articles by various attributes: Global reaction: Trump pulls US out of Paris Agreement on climate change

We can also tell that there seems to be more interest in the topic by looking at the statistics for visits to Skeptical Science. We for example had 48,000+ and 57,000+ unique visitors on June 1 and 2 respectively which is more than twice as many as we have on average and between 3 and 4 times more than on those days a year ago.

One area where we've been keeping very close tabs are the daily views for our rebuttals and by now, we have collected more than 49,000 datapoints for them since the beginning of 2017. The "Trump effect" is clearly visible when looking at the number of rebuttal views from mid-May to early June:

JumpInRebuttalViewsFigure 1: Number of views for each rebuttal across the different levels available (basic, intermediate and advanced). Shown are only rebuttals with at least 500 views on a given day. The big outlier is the rebuttal for "there's no consensus".

Here are some other highlights captured in early June (so the data goes up to June 2). You can see the larger version of the graphics by clicking on them. The top-most viewed rebuttals are calculated by adding up the views of all three available levels basic, intermediate and advanced for each month:

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3 comments


The Larsen C ice shelf collapse hammers home the reality of climate change

Posted on 12 June 2017 by John Abraham

Very soon, a large portion of an ice shelf in Antarctica will break off and collapse into the ocean. The name of the ice shelf is Larsen C; it is a major extension from of the West Antarctic ice sheet, and its health has implications for other ice in the region, and sea levels globally.

How do we know a portion is going to collapse? Well, scientists have been watching a major rift (crack) that has grown in the past few years, carving out a section of floating ice nearly the size of Delaware. The speed of the crack has increased dramatically in the past few months, and it is nearly cracked through.

Larsen crack

Crack in Larsen C ice shelf. Photograph: Ted Scambos, NSIDC

Project Midas provides frequent updates on the Larsen C shelf. You can read a summary there, which reports:

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13 comments


2017 SkS Weekly Climate Change & Global Warming Digest #23

Posted on 11 June 2017 by John Hartz

Story of the Week... Editorial of the Week... SkS Highlights... El Niño/La Niña Update... Toon of the Week... Quote of the Week... Graphic of the Week... SkS in the News... Photo of the Week... SkS Spotlights... Video of the Week... Reports of Note... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

June 2017 ENSO update: pancake breakfast 

A change is afoot! After months of suggesting an elevated chance for El Niño to develop, the CPC/IRI forecast has flattened out, and neutral conditions are expected (50-55% chance) to continue through the fall.

A recipe for neutral

In fact, the Nino3.4 region (a key ENSO monitoring area in the tropical central Pacific) is hovering around 0.5°C warmer than the long-term average. Yep, that’s the threshold for El Niño, but surely you remember that ENSO is a seasonal phenomenon, meaning those warmer sea surface temperatures need to stick around for several months—long enough to provoke an atmospheric response

Monthly sea surface temperature Nio 3.4 index

Monthly sea surface temperature in the Niño 3.4 region of the tropical Pacific compared to the long-term average for all years starting off from moderate-to-strong El Niño since 1950, showing how 2016 (blue line) compares to other events. Climate.gov graph based on ERSSTv4 temperature data.

Despite the warmer sea surface temperatures, the atmosphere is not behaving like El Niño. During May, the indicators that we track looked very average, including both the upper-level and near-surface winds over the equatorial Pacific and the amount of rain and cloudiness in the central Pacific and Indonesia. The indexes that measure the difference in the atmospheric pressure between the central Pacific and the far western Pacific, the Southern Oscillation Index and the Equatorial Southern Oscillation Index, were both close to zero in May, indicating, again: neutral conditions.

Most of the recent forecast models predict that the Niño3.4 region will move closer to average temperatures over the next few months. The average of all the dynamical model forecasts in the North American Multi-Model Ensemble flattens out at slightly above the long-term mean for the rest of this year. Averaging all model forecasts together usually produces the best forecast, because it reduces the noise and highlights the signal. Stay tuned—next month, I’m writing a post all about computer climate models. (Try to contain your excitement!) 

NMME plume graph June2017

Climate model forecasts for the Niño3.4 Index, from the North American Multi-Model Ensemble (NMME). Darker purple envelope shows the range of 68% of all model forecasts; lighter purple shows the range of 95% of all model forecasts. NOAA Climate.gov image from CPC data.

Combine these neutral atmospheric conditions, cooling forecasts, and the lack of any substantial warmth under the surface of the Pacific, and you get the current forecast of an approximately 50-55% chance of continuing neutral conditions through the fall. 

June 2017 ENSO update: pancake breakfast by Emily Becker, ENSO Blog, NOAA Climate.gov, June 8, 2017 

Read more...

5 comments


2017 SkS Weekly Climate Change & Global Warming News Roundup #23

Posted on 10 June 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Trump’s Climate-Change Sociopathy 

Trump & Paris Climate Accord

Win McNamee/Getty Images

President Donald Trump’s withdrawal of the United States from the Paris climate agreement is not just dangerous for the world; it is also sociopathic. Without remorse, Trump is willfully inflicting harm on others. The declaration by Nikki Haley, the US ambassador to the United Nations, that Trump believes in climate change makes matters worse, not better. Trump is knowingly and brazenly jeopardizing the planet.

Trump’s announcement was made with a bully’s bravado. A global agreement that is symmetric in all ways, across all countries of the world, is somehow a trick, he huffed, an anti-American plot. The rest of the world has been “laughing at us.”

These ravings are utterly delusional, deeply cynical, or profoundly ignorant. Probably all three. And they should be recognized as such.

Trump’s Climate-Change Sociopathy, Commentary by Jeffry D Sachs*, Project Syndicate, June 7, 2017

*Jeffrey D. Sachs, Professor of Sustainable Development and Professor of Health Policy and Management at Columbia University, is Director of Columbia’s Center for Sustainable Development and of the UN Sustainable Development Solutions Network. His books include The End of Poverty, Common WealthThe Age of Sustainable Development, and, most recently, Building the New American Economy.

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73 comments


SkS Analogy 7 - Christmas Dinner and the Faux Pause

Posted on 9 June 2017 by Evan

Tag Line

Saying “No warming” since the last El Nino is like
Saying “No weight gain” since the last Christmas dinner.

Elevator Statement

On Christmas eve you eat a big dinner, with lots of seconds, gravy, ooey gooey sweet potatoes with more sweet than potatoes. After the monster dinner, generous helping of pie, ice cream and lots more. You weigh yourself after the “dinner”. The next morning you find creative ways to get rid of the food you “ate” the night before, all of it (and more) ending up in the “waste” bin. You weigh yourself again, for comparison.

Hurrah, a new weight-loss technique. How to lose 5 lbs. (or more) in one delightful day. For the next month you note that you have not gained a single ounce since that gorging Christmas dinner. In fact, you’ve managed to keep your weight below the Christmas-eve measurement. Weight-loss is easy: just push your weight up momentarily to some unsustainably high weight, and then eat a more modest diet thereafter.

This tale would seem absurd, except this is exactly what educated, well-paid senators of the USA say on a regular basis. They substitute 1998 (the year of a monster El Nino) for Christmas dinner, they substitute temperature for body weight, and then say “No warming in __ years”, and neglect to note that the start of the “arbitrary” time period they’ve chosen was a monster El Nino. This Zombie Myth keeps on walking, eating the brains of many, despite the fact that we’ve notched record warm years 3 years in a row (i.e., 2014, 2015, and 2016). With the record warmth we’ve had, it’s possible we’re in the middle of the next Christmas “Dinner”.

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