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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?

 


Trump has launched a blitzkrieg in the wars on science and Earth’s climate

Posted on 28 March 2017 by dana1981

Today, Trump signed executive orders taking aim at America’s climate policies. On the heels of a report finding that the world needs to halve its carbon pollution every decade to avoid dangerous climate change, Trump’s order would instead increase America’s carbon pollution, to the exclusive benefit of the fossil fuel industry. 

Trump’s anti-climate executive orders

One part of the executive order tells the EPA to review and revise (weaken) its Clean Power Plan and methane regulations. However, revising these regulations isn’t so simple. It requires proceeding through the same years-long rulemaking process the EPA used to create the rules in the first place. This involves considering the scientific evidence, crafting draft rules, responding to millions of public comments, and defending the new plan in court. Environmental attorneys are confident “this is another deal President Trump won’t be able to close.

A second part of the executive order tells the EPA to ignore the government’s estimated price on carbon pollution. The Republican Party wants to lower the current estimate, but most evidence indicates the government is dramatically underestimating the cost of carbon pollution. Trump gets around this inconvenient evidence by ordering the EPA to simply deny the existence of those costs.

A third part of the executive order ends a moratorium on new coal leases on public lands before a review is completed to determine if taxpayers are being shortchanged due to the lands being sold too cheaply. Environmental groups are set to immediately challenge this order. Regardless, lifting the moratorium would have little effect on coal production or mining jobs.

EPA administrator Scott Pruitt would undoubtedly be happy to follow Trump’s orders. In his previous job as Oklahoma Attorney General and fossil fuel industry puppet, one of Pruitt’s 14 lawsuits against the EPA was aimed at the Clean Power Plan. However, the Clean Air Act requires the government to cut carbon pollution. Trump and Pruitt may not like it, but the law, scientific evidence, and public opinion fall squarely against them.

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PBS is the only network reporting on climate change. Trump wants to cut it

Posted on 27 March 2017 by dana1981

Media Matters for America has published its annual review of American evening newscast climate coverage for 2016, and the results are stunning:

In 2016, evening newscasts and Sunday shows on ABC, CBS, and NBC, as well as Fox Broadcast Co.’s Fox News Sunday, collectively decreased their total coverage of climate change by 66 percent compared to 2015

In all of 2016, these news programs spent a combined grand total of 50 minutes talking about climate change. More than half of that come from CBS Evening News, which nevertheless only spent half as much time talking about climate change in 2016 as it had in 2015.

coverage

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2017 SkS Weekly Climate Change & Global Warming Digest #12

Posted on 26 March 2017 by John Hartz

Story of the Week... El Niño/La Niña Update... Toon of the Week... Quote of the Week... He Said What?... Graphic of the Week... SkS in the News... Photo of the Week... SkS Spotlights... Video of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

Ice at Both Poles Shrinks to Record Lows

Arctic Sea Ice and melt ponds in the ChukchiSea 

Here's another entry in the parade of sobering climate change records: The National Snow and Ice Data Center announced Wednesday that Arctic sea ice hit its maximum extent for the year on March 7, and it was the lowest in the 38 years of satellite records.

The total ice coverage as the winter drew to a close was 471,000 square miles less than the 1981-2010 average—meaning ice larger than the combined size of California, Oregon, Washington and Nevada failed to form this year.

"We have had three record-setting low years of maximum sea ice extent in a row," said Walter Meier, a research scientist specializing in sea ice at NASA's Goddard Space Flight Center.

After decades of expansion, the sea ice surrounding Antarctica, where the summer is just ending, also hit a record low, NSIDC reported. Its minimum extent for year was reached on March 3, and was roughly 900,000 square miles below the 1981-2010 late-summer average.

Ice at Both Poles Shrinks to Record Lows by Sabrina Shankman, InsideClimate News, Mar 22, 2017

El Niño/La Niña Update

The odds of El Niño's development by the late summer or early fall have increased, according to the latest output from forecast model guidance.

NOAA's Climate Prediction Center (CPC) officially declared La Niña's end in early February as sea temperatures have steadily warmed in the equatorial region of the central and eastern Pacific, and we're now in the neutral phase of the oscillation. Neutral means that neither La Niña or El Niño conditions exist.

As shown below, models currently suggest we'll be in the neutral category through the spring and into the early summer months (April-May-June, or AMJ), but after that, sea temperatures could be warm enough for El Niño conditions to take over.

Mid-March IRI/CPC Model-Based Probabilisitc ENSO Forecast

The chance for various phases of El Niño, according to IRI's mid-March model-based probabilistic forecast. Red bars show the probability of El Niño's development during each three-month period. (International Research Institute for Climate and Society)

El Niño's Odds to Return By Late Summer or Fall Increasing by Jonathan Belles & Brian Donegan, WunderBlog, Weather Undergound, Mar 23, 2017 

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2017 SkS Weekly Climate Change & Global Warming News Roundup #12

Posted on 25 March 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. Articles of signifigance as determined by the editor are highlighted in the Editor's Picks' section.

Editor's Picks

Record-breaking climate change pushes world into ‘uncharted territory’

 dry Cedro reservoir in Quixadá, Brazil

A boat lies in the dry Cedro reservoir in Quixadá, Brazil. Climate change increases the risk of extreme weather events like drought. Photograph: Evaristo Sa/AFP/Getty Images

The record-breaking heat that made 2016 the hottest year ever recorded has continued into 2017, pushing the world into “truly uncharted territory”, according to the World Meteorological Organisation.

The WMO’s assessment of the climate in 2016, published on Tuesday, reports unprecedented heat across the globe, exceptionally low ice at both poles and surging sea-level rise.

Global warming is largely being driven by emissions from human activities, but a strong El Niño – a natural climate cycle – added to the heat in 2016. The El Niño is now waning, but the extremes continue to be seen, with temperature records tumbling in the US in February and polar heatwaves pushing ice cover to new lows.

Record-breaking climate change pushes world into ‘uncharted territory’ by Damian Carrington, Guardian, Mar 20, 2017

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Elevator Pitches - Chapter 02 - Radiative Gases

Posted on 24 March 2017 by Rob Honeycutt

This is another excerpt from my book 28 Climate Change Elevator Pitches. I'll be publishing one chapter here on SkS each month.

[Click here for larger image]

Chapter 02

Radiative Gases

A Musical Basis for Scattering Heat

The scientific basis for understanding climate goes back to the 1820’s when brilliant French mathematician Joseph Fourier first proposed the idea that our planet’s atmosphere had heat-trapping properties. Fourier was trying to calculate what should be the temperature of a planet at our distance from the sun. He derived a figure about 33°C (59°F) colder than the actual average temperature of the Earth. For his figures to be correct, he thought gases in our atmosphere must have “radiative properties” with the capacity to absorb and re-emit heat energy. When visible sunlight passes through our atmosphere it warms the surface of the Earth. The heat that is emitted upward we refer to as infrared radiation, or IR. Infrared radiation is just another wavelength of energy which is invisible to the human eye, but we can feel that energy as heat. It’s this heat energy that is scattered by radiative gases in the atmosphere.

In the 1850’s a British scientist, John Tyndall, devised an apparatus enabling him to measure the heat absorbing properties of various gases. Earth’s atmosphere is composed primarily of nitrogen (78%) and oxygen (21%). The remaining 1 percent of gases are known as “trace gases.” Tyndall discovered that the radiative properties of nitrogen and oxygen are insignificant and transparent to infrared radiation (heat). But, he further discovered that some trace gases do efficiently block heat. 

But, how does this work? Why would one gas be transparent to heat and another gas block it? 

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New Video: It’s Alive – Microbes and Melt on the Greenland Ice Sheet

Posted on 23 March 2017 by greenman3610

This is a re-post from Climate Denial Crock of the Week

5 years ago the idea that microbial, or algal, growth on the Greenland ice sheet was not getting very much attention, although scientists have known for decades that ice was, in fact a habitat for some kinds of micro organisms.

In recent years, several research groups have been looking in detail at the darkening of the ice sheet – and understanding that, as the planet warms, and ice melts, more liquid water means more habitat for bugs, more darkening, more melt,..you get the picture.

I’ve been fortunate to be part of one of these groups, Dark Snow Project, from the beginning, and again fortunate to spend time on ice with members of a new initiative, called “Black and Bloom”, so named as it focuses not just on Black Carbon, a significant source of darkening and melt, but the specialized organisms “blooming” on the ice, shielding themselves from the intense glacial

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Global warming is increasing rainfall rates

Posted on 22 March 2017 by John Abraham

he world is warming because humans are emitting heat-trapping greenhouse gases. We know this for certain; the science on this question is settled. Humans emit greenhouse gases, those gases should warm the planet, and we know the planet is warming. All of those statements are settled science.

Okay so what? Well, we would like to know what the implications are. Should we do something about it or not? How should we respond? How fast will changes occur? What are the costs of action compared to inaction? These are all areas of active research.

Part of answering these questions requires knowing how weather will change as the Earth warms. One weather phenomenon that directly affects humans is the pattern, amount, and intensity of rainfall and the availability of water. Water is essential wherever humans live, for agriculture, drinking, industry, etc. Too little water and drought increases risk of wild fires and can debilitate societies. Too much water and flooding can occur, washing away infrastructure and lives.

It’s a well-known scientific principle that warmer air holds more water vapor. In fact, the amount of moisture that can be held in air grows very rapidly as temperatures increase. So, it’s expected that in general, air will get moister as the Earth warms – provided there is a moisture source. This may cause more intense rainfalls and snow events, which lead to increased risk of flooding. 

But warmer air can also more quickly evaporate water from surfaces. This means that areas where it’s not precipitating dry out more quickly. In fact, it’s likely that some regions will experience both more drought and more flooding in the future (just not at the same time!). The dry spells are longer and with faster evaporation causing dryness in soils. But, when the rains fall, they come in heavy downpours potentially leading to more floods. The recent flooding in California – which followed a very intense and prolonged drought – provides a great example.

Okay so what have we observed? It turns out our expectations were correct. Observations reveal more intense rainfalls and flooding in some areas. But in other regions there’s more evaporation and drying with increased drought. Some areas experience both.

Some questions remain. When temperatures get too high, there’s no continued increase in intense rain events. In fact, heavy precipitation events decrease at the highest temperatures. There are some clear reasons for this but for brevity, regardless of where measurements are made on Earth, there appears to be an increase of precipitation with temperature up until a peak and thereafter, more warming coincides with decreased precipitation. 

A new clever study by Dr. Guiling Wang from the University of Connecticut and her colleagues has looked into this and they’ve made a surprising discovery. Their work was just published in Nature Climate Change. They report that the peak temperature (the temperature where maximum precipitation occurs) is not fixed in space or time. It is increasing in a warming world. 

The idea is shown in the sketch below. Details vary with location but, as the world warms, there is a shift from one curve to the next, from left to right. The result is a shift such that more intense precipitation occurs at higher temperatures in future, while the drop-off moves to even higher temperatures. 

rainfall diagram

An idealized example of increasing precipitation curves as the world warms for the Midwest. Illustration: John Abraham

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In-depth: What Donald Trump’s budget means for US spending on climate change

Posted on 21 March 2017 by Guest Author

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

On Thursday, President Trump unveiled his first budget proposal. Entitled “America First: A budget blueprint to make America Great Again”, the document outlines how the new administration plans to “reprioritise Federal spending”, redirecting funding away from a suite of government agencies in favour of increases in defence and immigration enforcement spending.

A statement by President Trump insists the proposed cuts are “sensible and rational”, adding:

“Every agency and department will be driven to achieve greater efficiency and to eliminate wasteful spending in carrying out their honorable service to the American people.”

It’s worth noting that the document is only a “blueprint”, laying out the president’s priorities for the 2018 fiscal year. The full federal budget will be released later this Spring and must first pass through Congress for approval. In the meantime, it’s worth looking at which research programmes the new administration has in its sights and the consequences of the proposed cuts for climate science.

Four ‘Earth-viewing’ programmes scrapped at NASA

The president’s proposed budget allocates $19.1bn for the US National Aeronautics and Space Administration (NASA), representing a 0.8% cut from current levels.

In a statement on Thursday, NASA’s acting administrator Robert Lightfoot called this a “positive budget overall for NASA” that was “in line with our funding in recent years” and which is sufficient to enable NASA to “effectively execute our core mission for the nation”.

However, keeping an overall headline figure belies major changes to the agency’s priorities.

The budget proposes cutting NASA’s Earth science budget by $102m to $1.8bn, with four Earth science missions scrapped completely; DSCOVR, OCO-3, PACE and CLARREO Pathfinder.

The SpaceX Falcon 9 rocket set to launch NOAA’s Deep Space Climate Observatory spacecraft, or DSCOVR, awaits liftoff, 8 February 2015.

The SpaceX Falcon 9 rocket set to launch NOAA’s Deep Space Climate Observatory spacecraft, or DSCOVR, awaits liftoff, 8 February 2015. Credit: NASA/Kim Shiflett.

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19 House Republicans call on their party to do something about climate change

Posted on 20 March 2017 by dana1981

While the Trump administration is veering sharply toward climate science denial, 19 House Republicans have taken steps to pull the party in the direction of reality, and the need to combat the threats posed by human-caused climate change.

The Republican Climate Resolution

Last week, Congresswoman Elise Stefanik (R-NY), Congressman Carlos Curbelo (R-FL), and Congressman Ryan Costello (R-PA) led a group of 17 House Republicans in introducing a resolution that calls on Congress to develop policies to tackle climate change. 

The Republican Climate Resolution recognizes that environmental stewardship is a conservative principle, that policies should be based on scientific evidence and quantifiable facts, that climate change is having negative impacts and is viewed by the Department of Defense as a threat multiplier, and that we can and must take meaningful action to address these threats in a manner that doesn’t constrain the American economy:

...be it Resolved, That the House of Representatives commits to working constructively, using our tradition of American ingenuity, innovation, and exceptionalism, to create and support economically viable, and broadly supported private and public solutions to study and address the causes and effects of measured changes to our global and regional climates, including mitigation efforts and efforts to balance human activities that have been found to have an impact.

The Resolution has thus far been signed by House Republicans representing districts in New York, Pennsylvania, Florida, Nevada, Nebraska, Virginia, New Jersey, Utah, Washington, and South Carolina. 

The bipartisan Climate Solutions Caucus

Eleven of the Resolution’s signatories are also members of the Climate Solutions Caucus, as are Darrell Issa (R-CA) and Lee Zeldin (R-NY), who have not yet signed the Resolution. The Climate Solutions Caucus is a bipartisan group in the US House of Representatives – currently comprised of 13 Republicans and 13 Democrats – that explores policy options to address climate change.

Caucus members include some prominent conservative Republicans. Darrell Issa is the former chair of the House Oversight and Government Reform Committee, and Mia Love is viewed as a rising star in the party. Love featured in an episode of the acclaimed program Years of Living Dangerously:

Mia Love in Years of Living Dangerously

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2017 SkS Weekly Climate Change & Global Warming Digest #11

Posted on 19 March 2017 by John Hartz

Stories 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... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Stories of the Week...

Coral reef survival hinges on ‘urgent and rapid’ emissions cuts

Graveyard of Staghorn coral, Yonge reef, Northern Great Barrier Reef, October 2016.

Graveyard of Staghorn coral, Yonge reef, Northern Great Barrier Reef, October 2016. Credit: Greg Torda, ARC Centre of Excellence for Coral Reef Studies

The future of the Great Barrier Reef – and other reefs around the world – will ultimately depend on how successfully we can limit ocean warming.

This is the blunt conclusion of a new study, just published in Nature, which examines the impacts of recent coral bleaching events on Australia’s Great Barrier Reef. The event in 2016, for example, left just 9% of surveyed reefs untouched.

The study finds that sea surface temperature is the biggest driver of bleaching, while local efforts to improve water quality or restrict fishing have little impact on limiting its severity.

This means that “immediate action to curb future warming” is essential if coral reefs are to survive, the authors warn. 

Coral reef survival hinges on ‘urgent and rapid’ emissions cuts by Robert McSweeney, Carbon Brief, Mar 16, 2017

Global Heat Continues With Second-Hottest February

February was the second hottest on record for the planet, trailing only last year’s scorching February — a clear mark of how much the Earth has warmed from the accumulation of heat-trapping greenhouse gases in the atmosphere.

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2017 SkS Weekly Climate Change & Global Warming News Roundup #11

Posted on 18 March 2017 by John Hartz

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

Sun Mar 12, 2017

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Paced version of Denial101x starting on March 21!

Posted on 16 March 2017 by BaerbelW

The next iteration of our free online course, Making Sense of Climate Science Denial, starts on March 21 and will run for 8 weeks as a paced course.

The MOOC (Massive Open Online Course) is a collaboration between Skeptical Science and The University of Queensland and takes an interdisciplinary look at climate science denial. We explain the psychological drivers of denial, debunk many of the most common myths about climate change and explore the scientific research into how to respond to climate misinformation. With all the misinformation and outright lies coming out of Washington regarding climate science - not to mention many other topics - our MOOC will give you the knowledge to spot and the tools to effectively counter them.

The course first launched in April 2015. Since then, over 30,000 students from over 160 countries have enrolled in the course. Last year, we were honoured to be named one of the finalists for the first-ever edX Prize for Exceptional Contributions in Online Teaching and Learning (the prize went to TU Delft's Arno Smets). We've received some wonderful feedback from students who've taken the course, particularly teachers who are using our course videos in their classes. Here is a video compilation of some feedback from the students:

You can sign up for free via the edX website.

Hope to see you there!

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Ben Santer on Seth Meyer’s Late Show – How Climate Deniers Lie

Posted on 15 March 2017 by greenman3610

This is a re-post from Climate Crocks

The reason most people have not heard of Ben Santer is that, while his contributions to climate science have been massive and epic in importance, and his courage in standing up to an almost unparalleled barrage of attacks is legendary, Ben himself is one of the quietest, most unassuming people you will ever meet.


My conversations with Ben a few months ago lead me to believe he had decided it was time to be more public in his advocacy, and I guess this is evidence of that.

One of the burrs under Ben’s saddle in the last year has been Senator Ted Cruz’s brazen and dishonest claims about climate science, on display most prominently in a December 2015 Senate Hearing, where a veritable clown car of climate criminals were brought out to repeat some of the most eminently crushable distortions.  And Ben, in truest form, rather than just “arguing from authority” as one of the world’s highest experts, spent a year going thru the various claims, and publishing a point by point rebuttal.

Now see the video that drove Senator Cruz, and Breitbart crazy – Dr. Santer and other key scientists show precisely how this climate denial lie was constructed.

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A Perfect (Twitter) Storm

Posted on 14 March 2017 by Rob Honeycutt

Last week an entertaining barrage of tweets erupted from Dr. Gavin Schmidt's account in response to a blog piece written by Dilbert creator Scott Adams. Being that Adams' original tweet promoting his blog post makes the presumptuous claim of "saving the world" by teaching climate scientists how to communicate science, you can only imagine how this would raise the ire of more than a few actual real-life experts.

 

Aside from the ludicrous notion that saving the world somehow pivots on convincing "skeptics", Adams' fundamental fallacy is the notion that it's the job of climate scientists to convince "skeptics" that climate change is real. What we know from research is, when someone has taken a specific position as a "skeptic" of man-made climate change, adding more information generally produces a backfire effect. They actually reject the science more in response to more information. It doesn't matter how persuasive you are. Most anyone who has already made this choice is not going to be persuaded, regardless of how the science is packaged.

Schmidt's initial response suggests that he fully understands this, saying upfront that his comment would be unlikely to change Adams' thinking. And subsequent tweets from Adams confirm his expectation. But, for those who follow climate science and the public debate, Schmidt's tweets serve as an entertaining take down of Adams' untethered world-view.

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The fossil fuel industry's invisible colonization of academia

Posted on 13 March 2017 by Guest Author

On February 16, the Harvard Kennedy School’s Belfer Center hosted a film screening of the “Rational Middle Energy Series.” The university promoted the event as “Finding Energy’s Rational Middle” and described the film’s motivation as “a need and desire for a balanced discussion about today’s energy issues.” 

Who can argue with balance and rationality? And with Harvard’s stamp of approval, surely the information presented to students and the public would be credible and reliable. Right? 

Wrong.

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2017 SkS Weekly Climate Change & Global Warming Digest #10

Posted on 12 March 2017 by John Hartz

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

Top Stories of the Week...

This soil study has some deeply disturbing predictions about CO2 emissions

Field

LightRocket via Getty Images

new study published Thursday in the journal Science has determined that if organic carbon in deep layers of soil warms at a rate similar to surface layers it could result in a dramatic increase in carbon dioxide emissions by the end of the century, if not sooner.

According to research by scientists at the Department of Energy’s Lawrence Berkeley National Laboratory, deeper stores of carbon are more sensitive to warming than previously thought.

“Our calculations suggest that by 2100 the warming of deeper soil layers could cause a release of carbon to the atmosphere at a rate that is significantly higher than today, perhaps even as high as 30% of today’s human-caused annual carbon emissions depending on the assumptions on which the estimate is based,” said Caitlin Hicks Pries, a postdoctoral researcher in Berkeley Lab’s Climate and Ecosystem Sciences Division.

This soil study has some deeply disturbing predictions about CO2 emissions by Ari Phillips, Fusion, Mar 9, 2017 

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2017 SkS Weekly Climate Change & Global Warming News Roundup #10

Posted on 11 March 2017 by John Hartz

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

Sun Mar 5, 2017

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How Green is My EV?

Posted on 9 March 2017 by David Kirtley

One of the largest sources of CO2 pollution from the average American consumer is the family car. The EPA states that 26% of greenhouse gas (GHG) emissions come from all forms of transportation (2014 figures). The largest source of GHG emissions, at 30%, is the electric power sector. However, just recently the Energy Information Administration (EIA) announced that transportation emissions have now surpassed those from electric power generation. Whatever the exact numbers, it's clear that if we want to reduce our GHG emissions we need to work to reduce them from these two sectors.

As individuals we can make choices which help decrease our electricity usage: LEDs over incandescent light bulbs, smart thermostats, etc. If we can afford it, and if we have the right house orientation, we can take an even bigger bite out of our CO2 emissions by installing solar PV panels to produce some or all of our electricity. But to get the biggest bang for our buck, perhaps the single best thing we can do to decrease our emissions is to switch from a normal car (internal combustion engine, or ICE, vehicle) to an all-electric vehicle (EV).

About two years ago my wife and I needed a second car and we decided to buy a 2013 Nissan Leaf. But because we live in Missouri, where most of the electric power is generated by coal, I was concerned that I would just be switching from ICE CO2 emissions to coal-electric emissions. Would we really be making any difference?

To answer that question (and others about how to compare MPG, fuel costs, etc. between a typical ICE and an EV) I kept track of data and made some calculations over a year-long period from September 2015 until August 2016. We bought the Leaf in June 2015 but it took me a few months to come up with a system and get a handle on what information I needed and where to find it.

Gasoline vs. Kilowatt-hours

We have a good grasp of what a gallon of gas means in terms of how much it costs and probably how many miles it will take us in our ICE cars. The "fuel" for an EV is kilowatt-hours (kWh) of electricity. Comprehending something as amorphous as a kWh stored in my Leaf's battery took a bit of a mental leap for me. The Leaf has a gauge on the instrument panel which displays the battery's amount of charge in 2 kWh increments, which isn't a very fine gauge. But the Leaf also records and uploads information on every trip made: kWh consumed, miles driven, etc. I can access this finer-detailed information from a Nissan website (figure 1). Now that I knew how many miles and how many kWh I used each month, I could look at my monthly electricity bills to see how much the EV "fuel" cost.

Figure 1. Portion of a screenshot of the Nissan Leaf website showing data for August 1, 2016. I travelled 25.1 miles and used 6.2 kWh. The "CO2 Savings" is not very accurate because it doesn't take into consideration the CO2 emissions from the electricity produced to power the car.

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To tweet or not to tweet at Donald Trump? That was the question!

Posted on 8 March 2017 by BaerbelW , John Mason

Knowing Twitter to be the prefered means of communication for the current POTUS and that he “may” have a thing or two to learn about climate science, John Mason recently set out to explain the carbon cycle in a series of 49 tweets in a language we hoped Donald Trump would be able to grasp.

As John explained: “I often wonder if a lot of climate change communication follows formats that may be unattractive to some people. Lengthy posts complete with explanatory graphics are appreciated by many, but others simply may not have the time to work through them for all sorts of reasons. Yet, this should not exclude them from accessing information. So regardless of whether Trump read the tweets or not, I wanted to proceed with this as an experiment in making climate communication available to a wider demographic. The simpler the framing of information, the more quickly it may be scanned and absorbed. I picked a fairly complex aspect of planetary science - Earth’s Carbon Cycle - and set out to simplify it whilst keeping it consistent with what the science says.

So, on February 28, the tweets started to go out on Twitter in a little tweet storm:

Tweet-Storm-01

A good two hours later the final tweets were sent:

Tweet-storm-03

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Explainer: How much did climate change ‘cost’ in the 20th century?

Posted on 7 March 2017 by Guest Author

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

From heatwaves to hurricanes, working out the dollar cost of climate change is a tough task. Often used by policymakers to weigh up the costs and benefits of tackling rising emissions, the topic is not without controversy. A recent study suggesting that human-caused climate change brought benefits in the 20th century offers a good starting point to explore a few of the issues that surround this fraught, complex topic.

The research, published in the journal Public Library of Science, claims the world has experienced a “significant drop” in estimated climate impacts “since the late 1990s” and that the tendency for models to ignore natural fluctuations, not caused by greenhouse gases, could be “biasing the estimates”.

But climate scientists and economists that Carbon Brief spoke to say the study’s conclusions don’t stack up. What’s more, the paper’s odd use of outdated assumptions, old datasets and now-defunct models serve to muddy this already tricky-to-navigate subject.

The study uses a type of model that blends climate science and economics to retrospectively work out the cost of climate change in the 20th century. Known as Integrated Assessment Models (IAMs), these work by assigning monetary values to expected climate impacts at different levels of warming.

The authors use three different IAMs: DICE (Dynamic Integrated Climate-Economy model), developed by William Nordhaus, a professor of economics at Yale University; PAGE (Policy Analysis of the Greenhouse Effect model), developed by Chris Hope from the University of Cambridge; and FUND (Framework for Uncertainty, Negotiation and Distribution model), originally developed and now co-managed by Richard Tol, a professor at the University of Sussex and co-author on the new study.

Over time, all three models have been continually updated to reflect the evolving science on things such as climate sensitivity, adaptation, ice sheet melt and sea level rise. Despite the authors of the new paper stating that they employ “the most widely used IAMs”, they actually select outdated versions.

Agricultural wheeled irrigation sprinkling system in California Desert near a dirt road and a newly planted citrus grove. Credit: NicolasMcComber/iStock/Getty Images

Agricultural wheeled irrigation sprinkling system in California Desert near a dirt road and a newly planted citrus grove.  Credit: NicolasMcComber/iStock/Getty Images

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