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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?


The inter-generational theft of Brexit and climate change

Posted on 27 June 2016 by dana1981

In last week’s Brexit vote results, there was a tremendous divide between age groups. 73% of voters under the age of 25 voted to remain in the EU, while about 58% over the age of 45 voted to leave.

View image on Twitter

This generational gap is among the many parallels between Brexit and climate change. A 2014 poll found that 74% of Americans under the age of 30 support government policies to cut carbon pollution, as compared to just 58% of respondents over the age of 40, and 52% over the age of 65.

Inter-generational theft

The problem is of course that younger generations will have to live with the consequences of the decisions we make today for much longer than older generations. Older generations in developed countries prospered as a result of the burning of fossil fuels for seemingly cheap energy.

However, we’ve already reached the point where even contrarian economists agree, any further global warming we experience will be detrimental for the global economy. For poorer countries, we passed that point decades ago. A new paper examining climate costs and fossil fuel industry profits for the years 2008–2012 found:

For all companies and all years, the economic cost to society of their CO2 emissions was greater than their after‐tax profit, with the single exception of Exxon Mobil in 2008

For much of the time during which developed nations experienced strong economic growth as a result of fossil fuel consumption, we were unaware of the associated climate costs. We can no longer use ignorance as an excuse. And yet the older generations, who experienced the greatest net benefit from carbon pollution, are now the least supportive of taking responsibility to pay for it. The longer we delay, the more devastating the consequences will be for the younger generations.

Similarly, today’s youth who are early in their career paths will face the harshest consequences of the Brexit vote that was dominated by older voters. As Jack Lennard put it:



2016 SkS Weekly Digest #26

Posted on 26 June 2016 by John Hartz

SkS Highlights... Toon of the Week... Quote of the Week... He Said What?... SkS in the News...Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

SkS Highlights

Using the metric of number of comments garnered, the two most popular of the articles posted on SkS during the past week were:

Toon of the Week

 2016 Toon 26

Hat tip to I Heart Climate Scientists



2016 SkS Weekly News Roundup #26

Posted on 25 June 2016 by John Hartz

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

Sun June 19, 2016



Chatham House: Brexit could harm UK climate and energy policy

Posted on 24 June 2016 by Guest Author

This is a re-post from Sophie Yeo at Carbon Brief

The UK is better staying in the EU from the perspective of energy and climate change, according to a new paper by international affairs thinktank, Chatham House.

Carbon Brief has been tracking [views on Brexit's impacts] relating to climate and energy.  The latest offering from Chatham House is particularly thorough, as it spells out what the impacts for the UK’s energy system and climate goals might be under the various scenarios that could be adopted, should the UK vote to leave.

Chatham House, which conducts research on subjects including climate, economics, law and security, receives funding from more than 500 donors, including the European Commission, Shell, Rockefeller Foundation and a range of national governments. Itsays: “This diversity of global support is critical to the independence of the institute.”


No member state has left the EU before, which means there is no precedent for how exactly the UK might extricate itself from its relationship with the EU, and what kind of arrangement it might establish in its place.

Several countries outside the EU have a formal relationship with the bloc, to which the UK could subscribe. It is also possible that the UK could negotiate its own unique relationship with the EU.

Each option presents various choices and trade-offs that could impact climate change and energy policy, says the report. These include the degree of access that the UK has to Europe’s gas and electricity markets; the extent to which the UK would be able to influence EU decision-making on energy policies; and the ease with which a deal could be negotiated with other EU states and institutions.

The following table, taken from the report, summarises the various options that could be available to the UK in the case of a “Brexit”, and also what a remain vote would mean.

Summary of Brexit vs Remain models

Credit: UK Unplugged? Chatham House

In this table, EFTA stands for European Free Trade Association, an organisation that extends free trade to four non-EU states: Iceland, Liechtenstein, Norway and Switzerland. EEA stands for European Economic Area, which provides for the freedom of people, goods, services and capital between the 28 EU member states and Iceland, Liechtenstein and Norway. Acquis communautaire means the EU’s body of laws and rules.



97% global warming consensus paper surpasses half a million downloads

Posted on 23 June 2016 by dana1981

In 2013, a team of citizen science volunteers who collaborate on the climate myth debunking website published a paper finding a 97% expert consensus on human-caused global warming in peer-reviewed research. Over the past 3 years, that paper has been downloaded more than 500,000 times. For perspective, that’s 4 times more than the second-most downloaded paper in the Institute of Physics journals (which includes Environmental Research Letters, where the 97% consensus paper was published).

The statistic reveals a remarkable level of interest for a peer-reviewed scientific paper. Over a three-year period, the study has been downloaded an average of 440 times per day, and the pace has hardly slowed. Over the past year, the download rate has remained high, at 415 per day.

Follow-up paper second-most-read

The 97% study and other consensus research has been attacked and misrepresented, which led to a follow-up paper in which authors of seven previous climate consensus studies collaborated to settle the question once and for all. The two key conclusions from the paper were:

1) Depending on exactly how you measure the expert consensus, it’s somewhere between 90% and 100% that agree humans are responsible for climate change, with most of our studies finding 97% consensus among publishing climate scientists.

2) The greater the climate expertise among those surveyed, the higher the consensus on human-caused global warming.

That follow-up paper, published two months ago, has already been downloaded 45,000 times. Interestingly, the 2013 consensus paper has returned to the top spot as currently the most-read paper in Environmental Research Letters, with the 2016 follow-up study coming in second.



Analysis: Is the UK relying on ‘negative emissions’ to meet its climate targets?

Posted on 22 June 2016 by Guest Author

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

The Paris Agreement on climate change pledges to keep warming “well below 2C” and “pursue efforts” to limit the increase since preindustrial times to no more than 1.5C.

But what rarely gets discussed is that the modelling by scientists showing how this might be possible typically assumes that the world will deploy “negative emissions” technologies (NETs) later on this century.

In a week-long series of articles, Carbon Brief has been looking at NETs – the options,implicationshistory and feasibilityIn the last part of our series, we turn the spotlight on the UK to see if – and how – it might resort to “sucking” CO2 from the atmosphere, in order to help meet its climate targets in the future.


Does the UK need negative emissions?

A full seven years before the ink dried on the Paris Agreement, the UK was enshrining in law its own national commitment to tackling climate change.

In 2008, the UK’s parliament passed the Climate Change Act, which set a legally binding target for reducing greenhouse gas emissions in 2050 by 80%, relative to 1990 levels.

In light of the Paris Agreement’s tightened temperature limit – it was nudged from the older “below 2C compared to preindustrial levels” commitment to “well below” 2C – the Committee on Climate Change (CCC), the UK government’s independent advisory body, recently determined that the UK’s fifth carbon budget for the 2028-2032 period should remain unchanged. The government will formally respond to the CCC’s advice and set out the policies to meet the target later this year.

5th Carbon Budget, CCC, 2015.

Source: The Fifth Carbon Budget – The next step towards a low-carbon economy, Committee on Climate Change, 2015.

But, as far back as 2010, the UK’s Department for Energy and Climate Change (DECC) recognised that “negative emissions” would likely need to feature in the world’s effort to keeping the global temperature rise to below 2C by the end of this century. A DECC-commissioned study into the potential for negative emissions in the UK concluded:

“It seems increasingly likely that CO2 emissions will overshoot the limit on the cumulative total needed to limit a global temperature rise to below 2C above pre-industrial levels. It may therefore become necessary to remove CO2 from the atmosphere.”

Recognising that the UK needed a “robust strategic plan” to uphold its part of the bargain, the study examined potential approaches, concluding that bioenergy with carbon capture and storage (BECCS) had “the most immediate negative emissions potential” in the UK.

Similarly, a 2015 report by the CCC outlining the scientific context for the UK’s fifth carbon budget described BECCS as a “sensible way to maximise emissions reduction”.

How much could BECCS lower the UK’s emissions?

According to the 2010 DECC-commissioned study, carried out as part of the AVOID2project, a middle estimate for the negative emissions potential of BECCS using only domestically-sourced biomass is just under 50m tonnes of carbon dioxide equivalent per year (MtCO2e) by 2030. This is equivalent to about 10% of the UK’s current emissions. The authors concluded:

“[T]his may provide significant flexibility in delivering long-term GHG [greenhouse gas] reduction targets by offsetting emissions that are difficult to capture (e.g. from agriculture and transportation point sources).”

It would take about 11 years to scale-up BECCS to its full potential, the study said. There is also a fair amount of uncertainty around the figures, with estimates of negative emissions in the literature ranging from 18-80 MtCO2e (or 3-16% of the UK’s emissions in 2015). 

The 10% figure assumes that all coal plants in the UK are replaced with BECCS and that 90% of the CO2 released in combustion can be captured and sequestered. It also assumes that biomass plants run at a similar efficiency to coal power plants (around 40%).



A brief history of fossil-fuelled climate denial

Posted on 21 June 2016 by John Cook

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

The fossil fuel industry has spent many millions of dollars on confusing the public about climate change. But the role of vested interests in climate science denial is only half the picture.

Interest in this topic has spiked with the latest revelation regarding coalmining company Peabody Energy. After Peabody filed for bankruptcy earlier this year, documentation became available revealing the scope of Peabody’s funding to third parties. The list of funding recipients includes trade associations, lobby groups and climate-contrarian scientists.

This latest revelation is significant because in recent years, fossil fuel companies have become more careful to cover their tracks. An analysis by Robert Brulle found that from 2003 to 2010, organisations promoting climate misinformation received more than US$900 million of corporate funding per year.

However, Brulle found that from 2008, open funding dropped while funding through untraceable donor networks such as Donors Trust (otherwise known as the “dark money ATM”) increased. This allowed corporations to fund climate science denial while hiding their support.

The decrease in open funding of climate misinformation coincided with efforts to draw public attention to the corporate funding of climate science denial. A prominent example is Bob Ward, formerly of the UK Royal Society, who in 2006 challenged Exxon-Mobil to stop funding denialist organisations.

John Cook interviews Bob Ward at COP21, Paris.

The veils of secrecy have been temporarily lifted by the Peabody bankruptcy proceedings, revealing the extent of the company’s third-party payments, some of which went to fund climate misinformation. However, this is not the first revelation of fossil fuel funding of climate misinformation – nor is it the first case involving Peabody.

In 2015, Ben Stewart of Greenpeace posed as a consultant to fossil fuel companies and approached prominent climate denialists, offering to pay for reports promoting the benefits of fossil fuels. The denialists readily agreed to write fossil-fuel-friendly reports while hiding the funding source. One disclosed that he had been paid by Peabody to write contrarian research. He had also appeared as an expert witness and written newspaper op-eds.

John Cook interviews Ben Stewart, Greenpeace at COP21, Paris.



New methods are improving ocean and climate measurements

Posted on 20 June 2016 by John Abraham

I have often said that global warming is really ocean warming. As humans add more heat-trapping gases to the atmosphere, it causes the Earth to gain energy. Almost all of that energy ends up in the oceans. So, if you want to know how fast the Earth is warming, you have to measure how fast the oceans are heating up.

Sounds easy enough at first, but when we recognize that the oceans are vast (and deep) we can appreciate the difficulties. How can we get enough measurements, at enough locations, and enough depths, to measure the oceans’ temperatures? Not only that, but since climate change is a long-term trend, it means we have to measure ocean temperature changes over many years and decades. We really want to know how fast the oceans’ temperatures are changing over long durations.

But that isn’t all. Throughout the years, we have made changes to the measurement methods. From old canvas buckets that were dipped into waters which were then measured, to insulated buckets, to temperature probes on the hulls of ships, devices that would be dropped into deep ocean waters, and now the ARGO fleet, which is approximately 3,000 autonomous devices that are more-or-less equally distributed across the oceans. Each of these devices measures temperatures a little differently; they have biases. As you change from one set of instruments to another, you might see a cooling or warming effect related to the change in instruments, not because the water temperatures are changing. 

The seeming intractability of this problem is why I began studying it a few years ago. I have worked with colleagues to answer a very specific equation related to one of the most commonly employed ocean measurement devices, the eXpendable BathyThermograph (or XBT for short). For many years, these devices formed the backbone of ocean temperature measurements. My colleagues and I want to ensure measurements from XBTs are as accurate as possible.

These devices are used by navies to measure the depth of the thermocline. While that was their original mission, climate scientists have adopted the devices for determining long-term ocean temperature changes. The problem is that the devices are relatively simple; they are freely dropped into ocean waters. As they descend, like a spinning torpedo, they unwind a wire connected to a computer system on-board the ship. A sensor in the probe sends temperature information to the computer system and a recording is made. When the device expends its wire, the wire breaks and the device continues to fall until it impacts the ocean floor.

It’s important for scientists to know the depth of each temperature measurement that the probe makes. The problem is, the probe does not detect its depth. Rather, its depth is estimated by knowing how fast the probe falls in water. The probe weight is balanced by drag forced between the water and the device. If the knowledge of probe speed is not known accurately, it means a scientist may think the probe is at one depth when in fact, it’s at a different depth. This subtle uncertainty can lead to large uncertainties in the overall ocean heat content.



2016 SkS Weekly Digest #25

Posted on 19 June 2016 by John Hartz

SkS Highlights... Toon of the Week... Quote of the Week... They Said What?... SkS in the News... SkS Spotlights... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

SkS Highlights

John Cook's original cartoon, The Climate Contraian Guide to Managing Risk is the seventh in The Climate Reality Project's blog post, Climate Change Explained in 10 Cartoons. The cartoon and the accompanying text:

7. Risky Behaviour

 Climate Risk

Say you surveyed 100 structural engineers, and 97 said a nearby bridge is structurally unsound and driving over it would be dangerous. Would you take the advice of the only three who disagreed, and proceed to drive over that bridge day in and day out?

It’s the same thing with climate change: 97 percent (or more) of climate scientists say climate change is real, and caused by humans. So do you believe that other remaining 3 percent and ignore the risks? Here’s what would happen if you apply that same reasoning to other areas, according to Skeptical Science.

Toon of the Week

2016 Toon 25 



2016 SkS Weekly News Roundup #25

Posted on 18 June 2016 by John Hartz

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

Sun June 12, 2016



Timeline: How BECCS became climate change’s ‘saviour’ technology

Posted on 17 June 2016 by Guest Author

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

Bioenergy with carbon capture and storage – better known by the acronym “BECCS” – has come to be seen as one of the most viable and cost-effective negative emissions technologies.

Even though they have yet to be demonstrated at a commercial scale, negative emissions technologies – typically BECCS – are now included by climate scientists in the majority of modelled “pathways” showing how the world can avoid the internationally agreed limit of staying “well below” 2C of global warming since the pre-industrial era.

Put simply, without deploying BECCS at a global scale from mid-century onwards, most modellers think we will likely breach this limit by the end of this century.

But where did the idea for this “saviour” technology come from? Who came up with it? Who then developed and promoted the concept?

Continuing our week-long series of articles on negative emissions, Carbon Brief has looked back over the past two decades and pieced together the seminal moments – the conferences, the conversations, the papers – which saw BECCS develop into one of the key assumed options for avoiding dangerous climate change.

The interactive timeline above shows these moments in sequential order. But Carbon Brief has also spoken to the scientists who were instrumental to the concept first taking hold…

Beginnings of BECCS

In April 2001, a PhD student from Sweden travelled to the University of Cambridge to present his latest unpublished work to the 12th Global Warming International Conference and Expo. Kenneth Möllersten, who was studying at the Royal Institute of Technology in Stockholm, had spent much of the past 12 months thinking about how the Swedish paper industry might be able to financially benefit from the Kyoto carbon emissions trading system through capturing its factory emissions and sequestering them underground.

Kenneth Möllersten

Kenneth Möllersten

Sitting in the audience at Möllersten’s talk was a scientist called Michael Obersteiner based at Austria’s International Institute for Applied Systems Analysis (IIASA). Obersteiner approached Möllersten afterwards.

“He was quite excited and wanted to collaborate, so we decided that we should try to do something together,” says Möllersten, who now works as a senior scientific advisor for the Swedish Energy Agency.

A few weeks later, the two men picked up the conversation over the phone, explains Obersteiner:



Development banks threaten to unleash an infrastructure tsunami on the environment

Posted on 16 June 2016 by Guest Author

The ConversationBill Laurance, James Cook University

We are living in the most explosive era of infrastructure expansion in human history. The G20 nations, when they met in Australia in 2014, argued for between US$60 trillion and US$70 trillion in new infrastructure investments by 2030, which would more than double the global total value of infrastructure.

Some of the key players in this worldwide infrastructure boom are huge investors such as the World Bank. The past few years and decades have seen the rise of major new investment banks, such as the recently founded Asian Infrastructure Investment Bank (AIIB), and the dramatic growth of funds such as the Brazilian Development Bank (BNDES).

The new banks, along with traditional big lenders such as the World Bank, the International Monetary Fund, and the Asian, African, and Inter-American Development Banks, are very fond of funding big infrastructure such as roads, dams, gas lines, mining projects, and so on.

Some people had hoped that these banks would promote sustainable and socially equitable development, but it now seems that they could end up doing precisely the opposite.

The world’s rivers are imperilled by thousands of planned hydroelectric dams. Shown here is the Tapajós River in Brazil, for which a dozen mega-dams are currently planned. William Laurance



New study finds evidence for a 'fast' dinosaur extinction

Posted on 15 June 2016 by howardlee

Boring is beautiful when you’re studying a calamity, especially one as spectacular as the mass extinction that wiped out the dinosaurs. That’s because exciting sediments, full of variations and gaps, make it hard to disentangle the extinction signal from the noise of natural variability.

So you could say that James Witts, of the University of Leeds in the UK, lucked-out with an especially boring batch of sediments in Seymour Island on the Antarctic Peninsula (the part on the map that points up to South America). His study, recently published in the journal Nature Communications, catches the extinction of marine life in one of the most detailed records ever published for the end-Cretaceous. As Witts describes it:

The sedimentology is consistently, remarkably boring. More than 1,000 meters of sandy silt and silty sand! 

James Witts describes his new study

It took about 4 million years to deposit that sand in a sea bed over the crucial time before, during, and after the mass extinction. In all that time fossils accumulated steadily – mollusks, sharks, corals, crustaceans, marine reptiles – until suddenly they all stopped. The sediments continued steadily accumulating, but all the Cretaceous fossils disappeared within a few meters of each other. Rare fossils disappeared sooner, common fossils disappeared later, but there’s a fossil-free gap right below the layer that marks the end of the Cretaceous.

It doesn’t look like the environmental setting over the extinction itself changed significantly, so we can discount any rapid changes in water depth having an effect on the pattern of extinction we see from the fossil record.

Then there is a layer of dead fish.



Study: Most fossil fuels unburnable without carbon capture

Posted on 14 June 2016 by Guest Author

This is a re-post from Simon Evans at Carbon Brief

The majority of fossil fuel reserves are unburnable if the world is to avoid dangerous climate change, but carbon capture and storage (CCS) could “unlock” greater use, a new study concludes.

The white paper, from Imperial’s Sustainable Gas Institute, challenges previous findings that CCS makes little difference to the quantity of fossil fuels that can be burned, within a 2C carbon budget.

Carbon Brief runs through the report’s findings and what it might mean for fossil fuel firms.

Fossil framing

CCS has a decidedly mixed reputation. Some strongly support it, whereas many view it with suspicion, as a technological fix that promises to allow existing energy firms to continue business as usual.

Indeed, oil and gas majors, such as BPShell and ExxonMobil, are among the loudest CCS advocates. So it’s worth noting that the Sustainable Gas Institute was set up in 2014 with an £8.2m grant from oil and gas firm BG Group, which was recently bought by Shell.

Setting out its purpose, the new report says:

“This white paper has considered whether carbon capture and storage (CCS) technology has the potential to enable access to more fossil fuel reserves in the future, where these reserves would otherwise be ‘unburnable’.”

Note that this explicitly frames the question in terms of enabling access to more fossil fuels, rather than in terms of securing the energy the world needs while avoiding dangerous climate change. Fossil fuels are useful, but using them is not an end in itself.



The Grand Oil Party: House Republicans denounce a carbon tax

Posted on 13 June 2016 by dana1981

On Friday, the US House of Representatives voted on a Resolution condemning a carbon tax. As The Hill reported:

Lawmakers passed, by a 237-163 vote, a GOP-backed resolution listing pitfalls from a tax on carbon dioxide emissions and concluding that such a policy “would be detrimental to American families and businesses, and is not in the best interest of the United States.”

Six Democrats voted with the GOP for the resolution. No Republicans dissented.

The oil industry is scared of a carbon tax

ExxonMobil officially supports a carbon tax, but the company did not comment on the House Resolution prior to the vote. Meanwhile, the American Petroleum Institute, which is a key lobbying group of the oil industry, including ExxonMobil, publicly supported the anti-carbon tax resolution, as did Koch Companies Public Sector, LLC. Senator Sheldon Whitehouse (D-RI) suspects that the Resolution itself originated from the oil industry:



2016 SkS Weekly Digest #24

Posted on 12 June 2016 by John Hartz

SkS Highlights... El Niño is Over... Toon of the Week... Quote of the Week... SkS Spotlights... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

SkS Highlights

Using the metric of comments garnered, the two most popular of the articles posted on SkS during the past week were:

El Niño is Over

On Thursday, the National Oceanic and Atmospheric Administration (NOAA) announced that the past year’s El Niño was no more. The declaration comes a few weeks after Australia’s Bureau of Meteorology, the other big El Niño monitoring group, also declared it dead and gone.

That means ocean temperatures in the eastern tropical Pacific are now near normal. But they might not stay that way for long as odds are pointing to a cooling in the region that could herald the arrival of a La Niña event later this fall.

El Niño Had a Good Run, But Now It’s Over by Brian Kahn, Climate Central, June 9, 2016

Toon of the Week

2016 Toon 24 



2016 SkS Weekly News Roundup #24

Posted on 11 June 2016 by John Hartz

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

Sun June 5, 2016



Climate scientists have warned us of coral bleaching for years. It's here

Posted on 10 June 2016 by John Abraham

Readers may have noticed that it’s been about a month since my last article. In recent weeks I presented guest articles in place of my own pieces. The reason for my absence was due to the adoption I was finalizing in the USA (my second successful adoption!). Anyone who has adopted a child can attest to the time and travel requirements. I intend that this article marks my return to near weekly posting and I thank my readers for their patience.

Coral reefs are important for the health of the ocean biosystem; they support and harbor a high density of diverse organisms. While there are reefs located in many locations around the world, people often think first about the Great Barrier Reef off the Australian coast. It is known for its size and beauty; it brings travelers close to nature.

Scientists have investigated how reefs will fare in a changing world. The changing climate, poor management, pollution, overfishing, careless divers, and other factors may bring real risks to the health of reefs.

Just a few days ago, a world-leading organization released the results of a long-term study on the health of the Great Barrier Reef that may tell us about the health of reefs around the world. The organization ARC Centre of Excellence Coral Reef Studies found that a recent mass bleaching has killed 35% of corals on the northern and central Great Barrier Reef. 

The National Oceanic and Atmospheric Administration explains coral bleaching as events that cause the coral to expel algae that live in their tissues. Following the expelling, the corals whiten in color (which is why the term bleaching is used). The coral and the algae live in a symbiotic relationship; the algae provide nutrients for the coral. Without the algae, coral can be more susceptible to disease and death. It’s important to know that the coral can recover from a bleaching, but recovery depends on the extent and duration of the event and the general health of the coral.

This year’s incredible bleaching is not a one-time event. In fact, there have been many significant regional bleaching events and three global events over the past 18 years. In the current event, the extent of bleaching depends on location. The Great Barrier Reef extends over 2000 km. In the northern sector, almost all reefs experienced bleaching. The further south one travels, the less extensive the event because the warming was not as severe.

reef mortality

Map of estimated coral loss on the Great Barrier Reef in June 2016, Australia. Illustration: ARC Centre for Excellence in Coral Reef Studies



Ocean Heat Comes Back to Haunt Coral Reefs

Posted on 9 June 2016 by Rob Painting

As I predicted in August last year, the powerful El Niño of 2015-2016, in tandem with global warming, has seen a worldwide coral bleaching event unfold across the tropics. On Australia's Great Barrier Reef the bleaching is easily the worst on record with 93% of reefs experiencing bleaching ranging from minor to severe. However we won't know the full extent of  this global event until the end of the year, or perhaps 2017, when the bleaching is expected to have ended. Reports throughout the Pacific and Indian Ocean, however, hint that it could be the worst global bleaching event on record too, with a high rate of mortality likely. 

My prediction was rather stating the obvious as the oceans are warming and research in the last few decades has established that reef-building corals are near a high temperature tolerance threshold. Summer, combined with El Niño, is when sea surface temperatures in the tropics of each hemisphere tend to peak. As explained in my previous post, this has to do with year-to-year fluctuations in the rate at which the subtropical cell in the ocean transports heat poleward (meridionally) out of the tropics. The relaxation of the westward blowing trade winds, which accompanies El Niño, also allows heat buried in the subsurface ocean of the western tropical Pacific to surface and become entrained in the ocean's surface circulation. Accordingly, the climate model-based projections at NOAA's Coral Reef Watch were warning of thermal stress on the Great Barrier Reef, and elsewhere, as early as November 2015.

Figure 1 - Projected coral reef thermal stress (60% probability) for the period Dec 2015 to March 2016. Image from NOAA's Coral Reef Watch.

Although it only extends up to December 2014, and therefore excludes the 2015-2016 El Niño, the quality-controlled data provided by the Argo system of autonomous floats is able to provide a clearer picture of how this ENSO fluctuation affects the surface layers in the latitudes where almost all coral reefs reside - 30°N to 30°S. See Figure 2. 



Trump and global warming: Americans are failing risk management

Posted on 8 June 2016 by dana1981

Currently, about 40% of Americans support Donald Trump in the 2016 presidential election, and about 40% of Americans are not worried about global warming. While short of a majority, this is a substantial fraction of the American public failing to grasp the risks associated with a Donald Trump presidency and potentially catastrophic climate change impacts.

In Business InsiderJosh Barro recently wrote about the former:

Trump calls for a huge risk premium because, while he probably wouldn’t be a disastrous president, the low-probability disasters that he might cause would be immensely costly. Some of them involve nuclear weapons and global mass deaths. Pricing those risks in properly should push his share price comfortably below Clinton’s, even if you think she is very bad.

In most cases, Americans are good at managing risks. We buy insurance for our homes, cars, and health. We wear seat belts in cars, and far fewer Americans smoke today than just a few decades ago.




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