Extreme heat waves like the current string of scorching days in the Midwest have become more frequent worldwide in the last 60 years, and climate scientists expect that human-caused global warming will exacerbate the dangerous trend in coming decades. It comes with potentially life-threatening consequences for millions of people.

Research has shown that overall mortality increases by 4 percent during heat waves compared to normal days in the U.S. A study in the journal Environmental Health Perspectives in 2011 suggested that rising summer temperatures could kill up to 2,200 more people per year in Chicago alone during the last two decades of the 21st century.

"The climate is changing faster than we've ever seen during the history of human civilization on this planet, and climate change is putting heat waves on steroids," Katharine Hayhoe, director of the Climate Science Center at Texas Tech University, said during a news conference on Thursday. "Heat waves are getting more frequent and stronger."

Temperatures this week soared into the 90s from Minnesota to Iowa, combining with high humidity to send heat indices well above the 100-degree Fahrenheit mark, considered a threshold for conditions dangerous to human health.

Current temperatures in large parts of the Midwest have been rising steadily for more than 100 years, with accelerated warming in the past few decades. According to the 2014 National Climate Assessment, the average temperature in the region increased by more than 1.5 degrees Fahrenheit between 1900 and 2010. Between 1950 and 2010, the rate of increase doubled, and since 1980, the pace of warming is three times faster than between 1900 and 2010.

But while the Midwest joins the overall warming trend, it has not been hit frequently by summer heat waves, according to Ken Kunkel of NOAA's National Centers for Environmental Information

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Analysis: How UK leaving the EU would increase climate targets for others

Posted on 28 July 2016 by Guest Author

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

The European Commission has laid out proposals on dividing up 2030 emissions reduction goals for buildings, transport and agriculture.

The proposed 2030 Effort Sharing Regulation would allocate binding annual targets to each member state for sectors not covered by the EU Emissions Trading System (EU ETS). Countries would have to cut non-ETS emissions in 2030 by between zero and 40%, against 2005 levels.

Though uncertainty shrouds the UK’s future within the bloc following the Brexit vote, the proposal still includes the UK. It will also hand binding targets to Norway and Iceland, both non-EU member states.

Carbon Brief runs through the key points of the proposal and analyses what would happen if the UK were no longer part of the 2030 effort-sharing targets.

2030 targets

The EU has pledged to cut its greenhouse gas emissions in 2030 by at least 40% below 1990 levels. The ETS sector, including power stations and industry, will cut emissions in 2030 by 43% below 2005 levels (note the confusingly inconsistent base year). Non-ETS sectors, such as buildings and transport, will cut emissions in 2030 by 30% below 2005 levels.

The EU maintains that its 2030 target is in line with the goals of the Paris Agreement, which aims to keep temperature increases “well below 2C”. However, it has not changed its goal since Paris and Climate Action Tracker, a group of scientists and policy experts, says the EU’s pledge is “not yet sufficient” to be considered a fair share of global ambition.
Today’s proposal sets out how the 2030 non-ETS target of 30% below 2005 levels should be divided between the EU’s 28 (current) member states. The division of labour ranges from a 0% cut on 2005 levels for Bulgaria to a 40% reduction for Luxembourg and Sweden (see chart, below).

Proposed 2030 non-ETS emissions reduction targets for each EU member state, and the EU average. The reductions are relative to 2005 emissions. Source: European Commission. Chart by Carbon Brief.

Effort is shared out using two factors: first, countries with higher per-capita GDP are expected to do more; and, second, for those with above-average per-capita GDP, contributions are adjusted to reflect their cost-effective emissions-reduction potentials.

Broadly speaking, this division of labour means that the EU’s richest nations, including Sweden, Germany and the UK, are at the top end of ambition within the EU, while eastern European member states including Poland and Bulgaria, are at the bottom end.

When the non-ETS targets for 2020 were handed out, only GDP per-capita was taken into account. The 2020 targets are shown below.

Non-ETS emissions reduction targets for 2020 for each member state, and the EU average. The reductions are relative to 2005 emissions. Source: European Commission. Chart by Carbon Brief.

The new adjustment for cost-effective reduction potentials reduces the effort required by Ireland, Spain and Finland while increasing it for Germany. Changes in relative GDP since 2009 mean some countries, particularly Greece, will have less stringent targets for 2030 than they do for 2020.

Differences between proposed 2030 emissions reduction targets and what would have been expected if the 2020 division of labour had been repeated. Source: Carbon Brief analysis.

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Climate models are accurately predicting ocean and global warming

Posted on 27 July 2016 by John Abraham

For those of us who are concerned about global warming, two of the most critical questions we ask are, “how fast is the Earth warming?” and “how much will it warm in the future?”.

The first question can be answered in a number of ways. For instance, we can actually measure the rate of energy increase in the Earth’s system (primarily through measuring changing ocean temperatures). Alternatively, we can measure changes in the net inflow of heat at the top of the atmosphere using satellites. We can also measure the rate of sea-level rise to get an estimate of the warming rate. 

Since much of sea-level rise is caused by thermal expansion of water, knowledge of the water-level rise allows us to deduce the warming rate. We can also use climate models (which are sophisticated computer calculations of the Earth’s climate) or our knowledge from Earth’s past (paleoclimatology). 

Many studies use combinations of these study methods to attain estimates and typically the estimates are that the planet is warming at a rate of perhaps 0.5 to 1 Watt per square meter of Earth’s surface area. However, there is some discrepancy among the actual numbers.

So assuming we know how much heat is being accumulated by the Earth, how can we predict what the future climate will be? The main tool for this is climate models (although there are other independent ways we can study the future). With climate models, we can play “what-if scenarios” and input either current conditions or hypothetical conditions and watch the Earth’s climate evolve within the simulation.

Two incorrect but nevertheless consistent denial arguments are that the Earth isn’t warming and that climate models are inaccurate. A new study, published by Kevin Trenberth, Lijing Cheng, and others (I was also an author) answers these questions.

The study was just published in the journal Ocean Sciences; a draft of it is available here. In this study, we did a few new things. First, we presented a new estimate of ocean heating throughout its full depth (most studies only consider the top portion of the ocean). Second, we used a new technique to learn about ocean temperature changes in areas where there are very few measurements. Finally, we used a large group of computer models to predict warming rates, and we found excellent agreement between the predictions and the measurements.

According to the measurements, the Earth has gained 0.46 Watts per square meter between 1970 and 2005. Since, 1992 the rate is higher (0.75 Watts per square meter) and therefore shows an acceleration of the warming. To put this in perspective, this is the equivalent of 5,400,000,000,000 (or 5,400 billion) 60-watt light bulbs running continuously day and night. In my view, these numbers are the most accurate measurements of the rate at which the Earth is warming.

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More CO2 won’t help northern forests or stave off climate change

Posted on 26 July 2016 by Guest Author

Noah Charney, Postdoctoral Research Associate of Ecology and Evolutionary Biology, University of Arizona

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

We’ve heard the predictions of how greenhouse gas emissions will drive changes in the temperatures and precipitation people experience. But how these changes affect the world’s forests has broad implications for the future as well.

Could warmer winters, and thus longer growing seasons, cause trees to grow faster? If so, perhaps faster tree growth could slow the pace of climate change, since trees suck carbon out of the air as they grow.

Or perhaps hotter summers will mean more drought-like conditions, thereby hampering trees' ability to grow and thus cause deterioration of our woodlands.

In a recent paper, my colleagues and I set out to make a map of how climate change might influence tree growth across the entire continent of North America. To do this, we dug into historical records of tree growth over the period 1900-1950 collected by many dedicated field ecologists over the decades and deposited in the International Tree Ring Data Bank.

What we found was that the daily life of trees across much of North America will become more challenging, despite the potential benefit that rising carbon dioxide concentrations may have for trees. This is contrary to some scientists' hopes that climate change will strongly benefit northern latitude forests.

How trees respond to climate

The first hurdle in predicting future tree growth is to understand how trees in different ecosystems respond to climate fluctuations.

You might guess that in cold northern forests, a little heat might help trees grow, whereas more heat in the desert Southwest is likely the last thing trees there want. This observation motivated previous scientists to formulate a “boreal greening” hypothesis – that global warming will cause northern boreal forests to grow faster and help mitigate climate change.

We used the historic tree ring data to map the relationship between regional climate and tree growth. Matching each growth ring to the weather patterns in the corresponding year, we can get a sense for how trees respond to climate fluctuations. For instance, we saw that above-average June temperatures caused faster tree growth in places with climates similar to Fairbanks, Alaska, but slower growth in Phoenix-like climates.

Boreal forests such as this one in Alaska are projected to enter into a different climatic zone from rising temperatures due to climate change and fare worse in the future. akgypsy37/flickr, CC BY-NC-ND

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These are the best arguments from the 3% of climate scientist 'skeptics.' Really.

Posted on 25 July 2016 by dana1981

When I give a presentation and mention the 97% expert consensus on human-caused global warming, I’m often asked, “what’s the deal with the other 3%?”. These are the publishing climate scientists who argue that something other than humans is responsible for the majority of global warming, although their explanations are often contradictory and don’t withstand scientific scrutiny.

A few months ago, the world’s largest private sector coal company went to court, made its best scientific case against the 97% expert consensus, and lost. One of coal’s expert witnesses was University of Alabama at Huntsville climate scientist Roy Spencer - a controversial figure who once compared those with whom he disagreed to Nazis, and has expressed his love for Fox News.

Last week, Spencer wrote a white paper for the Texas Public Policy Institute (TPPI) outlining the contrarian case against climate concerns. TPPI is part of the web of denial, having received substantial funding from both the tobacco and fossil fuel industries, including $65,000 from ExxonMobil and at least $911,499 from Koch-related foundations since 1998, and over $3 million from “dark money” anonymizers Donors Trust and Donors Capital Fund.

Spencer’s arguments should of course be evaluated on their own merits, regardless of who commissioned them. However, it turns out that they have little merit on which to stand. The white paper is a classic example of a Gish Gallop – producing such a large volume of nonsense arguments that refuting all of them is too time-consuming. NASA Goddard director Gavin Schmidt rightly described Spencer’s paper as:

A mishmash of myths

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2016 SkS Weekly Digest #30

Posted on 24 July 2016 by John Hartz

SkS Highlights

The best strategies to keep bodies cool in a heatwave, according to researchers by John Abraham (Climate Consensus-the 97%, Guardian) attracted the highest number of comments of the articles posted on SkS during the past week. Study links heatwave deaths in London and Paris to climate change by Robert McSweeney (Carbon Brief) garnered the second highest number of comments.

Toon of the Week

Hat tip to I Heart Climate Scientists

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2016 SkS Weekly News Roundup #30

Posted on 23 July 2016 by John Hartz

Sun July 17, 2016

• Reshuffle: DECC folded into new department headed by Greg Clark by Sophie Yeo, Carbon Brief, July 14, 2016
• Hooked! The Unyielding Grip of Fossil Fuels on Global Life by Michael Klare, TomDispatch/Alternet, July 15, 2016
• Alaska has been breaking heat records as if it's going out of style by Andrew Freedman, Mashable, July 14, 2016
• High temperatures, 'corn sweat' form dangerous heat dome over U.S. by Jennifer Gray and Dave Hennen, CNN, July 17, 2016
• Cyclones set to get fiercer as world warms by Alex Krby, Climate News Network, July 16, 2016
• Earth's 5th Costliest Non-U.S. Weather Disaster on Record: China's $22 Billion Flood by Jeff Masters & Bob Henson, WunderBlog, Weather Underground, July 16, 2016
• The Carbon Brief Interview: Mark Watts by Sophie Yeo, Carbon Brief, July 13, 2016
• Climate change needs to be treated with more urgency, says scientist by Jamie Morton, NZ Herald, July 18, 2016

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Study links heatwave deaths in London and Paris to climate change

Posted on 22 July 2016 by Guest Author

This is a re-post from Carbon Brief by Robert McSweeney

In 2003, more than 70,000 people across Europe died in a sweltering heatwave that spanned much of the summer.

France was among the worst-affected countries, with 15,000 deaths in August alone. In the UK, the summer saw more than 2,000 heat-related fatalities.

A new first-of-a-kind study works out how many of the deaths in Paris and London are down to the heatwave being intensified by human-caused climate change.

The findings suggest that 506 of the 735 summer fatalities in Paris in 2003, and 64 of the 315 in London, were a result of human influence on the climate.

Human influence

The European summer heatwave of 2003 has been something of a focal point for scientists looking at if and how human-caused climate change influences extreme weather events.

In 2004, the heatwave was the subject of the first ever attribution study, which found that climate warming from human activity had at least doubled the likelihood of such an event. In 2014, another study found that a similar “extremely hot” summer in Europe has become 10 times more likely over the last 10-15 years because of climate change.

Taking this a step further, the new study, published in Environmental Research Letters, attributes the number of deaths during the 2003 heatwave to our warming climate.

The study makes use of the weather@home project, where members of the public offer spare capacity on their home computers for scientists to run model simulations.

The researchers ran thousands of simulations of European weather in 2003. One set of model runs simulated the weather according to the climate as it was – i.e. in a world warmed by past greenhouse gas emissions. The second set simulated the weather in a hypothetical world with no human influences on climate.

The researchers then compared the heat and humidity between the hypothetical world and the one better matched to reality to see how they affect the number of premature deaths in the summer of the same year. Lead author Dr Daniel Mitchell, a researcher in the Department of Physics at the University of Oxford, explains to Carbon Brief:

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The best strategies to keep bodies cool in a heatwave, according to researchers

Posted on 21 July 2016 by John Abraham

As we hit high-heat season in the Northern Hemisphere, it is useful to clarify tactics that can be used to help maintain healthy body temperatures. These tips are not commonly known and can be adopted by anyone, anywhere. While I am a climate scientist, my funded work is in the area of heat transfer, particularly in the human body. I work with medical companies to maintain healthy body temperatures during surgeries or other situations. I also deal with scald burns and I often serve in burn injury litigation.

Here are some key tips. First, avoid hyperthermia in the first place – drink plenty of fluids, avoiding direct sunlight, trying to get a respite from heat each day, avoiding physical exertion during the hottest parts of the day are all great suggestions. But, if you need to lower a body temperature, Dr. Robert Huggins, VP of Research and Athlete Performance at the Korey Stringer Institute suggests:

The general rule is to cool as much of the body’s surface as possible …. the larger the area you cool and the colder the device you use to cool it the faster the cooling rate. An appropriate goal is to use a method that cools at a rate of 0.15°C per minute. This can typically be achieved by immersion techniques using a tub or other basin filled with ice cold water or via rotating cold ice towels over the body.

During exercise if there is limited access to the entire body (e.g. football or fire-fighters), cooling the hands, face and feet will help, and if possible, use a fan to increase evaporation from these surfaces. However, when heat stroke is suspected, these strategies are not nearly as effective as whole body methods; opt for immersion cooling.

So how do you know if someone is suffering from hyperthermia or heat stroke? A great resource is the Korey Stringer Institute, which lists many symptoms for heat stress such as fatigue, weakness, pale appearance, headache, nausea, vomiting, fainting, dizziness, and others. The heat stroke treatment they recommend, while geared toward athletes, is still useful for the rest of us. 

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Cold and calculating: what the two different types of ice do to sea levels

Posted on 20 July 2016 by Guest Author

Matt King, Professor, Surveying & Spatial Sciences, School of Land and Food, University of Tasmania; Ben Galton-Fenzi, Senior Scientist, and Will Hobbs, Physical Oceanographer, Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania

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

It was back in 250ʙⅽ when Archimedes reportedly stepped into his bathtub and had the world’s first Eureka moment – realising that putting himself in the water made its level rise.

More than two millennia later, the comments sections of news stories still routinely reveal confusion about how this same thing happens when polar ice melts and sea levels change.

This is in marked contrast to the confidence that scientists have in their collective understanding of what is happening to the ice sheets. Indeed, the 2014 Assessment Report of the Intergovernmental Panel on Climate Change reported “very high confidence” that the Greenland Ice Sheet was melting and raising sea levels, with “high confidence” of the same for the Antarctic Ice Sheet.

Despite this, commenters below the line on news stories frequently wonder how it can be true that Antarctica is melting and contributing to sea-level rise, when satellite observations show Antarctic ice expanding.

Unravelling the confusion depends on appreciating the difference between the two different types of ice, which we can broadly term “land ice” and “sea ice” – although as we shall see, there’s a little bit more to it than that. The two different types of ice have very different roles in Earth’s climate, and behave in crucially different ways.

Sea levels rise when ice resting on land, grounded ice, melts (often after forming icebergs). Floating sea ice that melts has a very important role in other areas of our climate system.

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Reshuffle: DECC folded into new department headed by Greg Clark

Posted on 19 July 2016 by Guest Author

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

Theresa May, the new prime minister, has axed the Department of Energy and Climate Change, by folding it into the Department for Business, Innovation & Skills and thereby creating a new ministry called the Department for Business, Energy and Industrial Strategy.

Greg Clark, who was the secretary of state for the Department for Communities and Local Government under David Cameron, was appointed head of the new department during a dramatic cabinet reshuffle on Thursday.

Reacting to his appointment, Clark said:

I am thrilled to have been appointed to lead this new department charged with delivering a comprehensive industrial strategy, leading government’s relationship with business, furthering our world-class science base, delivering affordable, clean energy and tackling climate change.

It is not Clark’s first brush with the climate change brief. Between 2008 and 2010, while the Conservatives were in opposition, he was shadow secretary for energy and climate change.

In this time, he made his views clear on climate change. Here are some quotes that might give us some idea of what to expect from him in the future.

2009: On climate science

2009: On extreme risks

2009: On climate sceptics

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Déjà vu: as with tobacco, the climate wars are going to court

Posted on 18 July 2016 by dana1981, JohnMashey

Investigative journalism has uncovered a “web of denial” in which polluting industries pay “independent” groups to disseminate misinformation to the public and policymakers. The same groups and tactics were employed first by the tobacco industry, then fossil fuel companies. Big Tobacco has been to court and lost; now it’s Big Oil’s turn. Political leaders are choosing sides in this war.

Research by Inside Climate News revealed that Exxon did top notch climate science research in the late 1970s and early 1980s, which revealed the dangers its products posed via climate change. Soon thereafter, Exxon launched misinformation campaigns by funding “think tanks” and front groups to manufacture doubt about climate science and the expert consensus on human-caused global warming.

What #ExxonKnew vs what #ExxonDid. Illustration: John Cook, SkepticalScience.com

Exxon wasn’t alone. Koch Industries, Peabody Energy, and other fossil companies have similarly funneled vast sums of money to these groups. Last week, Senate Democrats, including presidential candidate Bernie Sanders and vice presidential contenders Elizabeth Warren and Al Franken signed a Resolution expressing congressional disapproval of the fossil fuel industry’s misinformation campaign.19 Senate Democrats also took to the floor of the Senate to speak out against the web of denial, with repeated references to the tobacco/fossil connections.

Senator Elizabeth Warren speaking about the web of denial on the Senate floor.

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