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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 war on coal is over. Coal lost.

Posted on 16 October 2017 by dana1981

Last week, Trump’s EPA administrator Scott Pruitt announced, “the war on coal is over.” If there ever was a war on coal, the coal industry has lost. According to a new report from the Union of Concerned Scientists, many old American coal power plants are being retired or converted to natural gas, and new coal power plants aren’t being built because they’ve become more expensive than natural gas, wind, and solar energy:

The share of US electricity coming from coal fell from 51 percent in 2008 to 31 percent in 2016—an unprecedented change. New UCS analysis finds that, of the coal units that remain, roughly one in four plans to retire or convert to natural gas; another 17 percent are uneconomic and could face retirement soon.

Natural gas has now surpassed coal to supply 32% of US electricity (up from 21% in 2008), and solar and wind are up to 10% (from 3% in 2008).

US power

 Evolution of the American power grid mix since 1960. Illustration: Carbon Brief

This trend will continue.



2017 SkS Weekly Climate Change & Global Warming Digest #41

Posted on 15 October 2017 by John Hartz

Story of the Week... El Niño/La Niña Update... Toon of the Week... Graphic of the Week... SkS Spotlights... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

Firefight in Sonoma County reaches second week as flames force thousands to evacuate

Sonoma County CA Wildfire

Firefighters from Compton put a scratch and wet line around a fire on Lovall Valley Road in Somona, Saturday, Oct 14, 2017. (Kent Porter/The Press Democrat) 2017

An army of firefighters with a larger aerial arsenal at their disposal held their ground and made some gains Saturday on devastating wildfires ravaging Wine Country, but evacuation orders that forced thousands from their homes before dawn and a rising death toll were clear reminders of the peril that still grips the region.

Northeast winds that arrived early Saturday whipped up a new fire in the hills outside eastern Santa Rosa, and spread an existing blaze outside Sonoma, prompting another round of nighttime evacuation orders.

Thousands of Santa Rosa residents were forced to leave — some for the second time since last Sunday — while others faced their first mandatory orders in Sonoma. 

Firefight in Sonoma County reaches second week as flames force thousands to evacuate by Kevin McCallum & Randi Rossmann, The Press Democrat, Oct 15, 2017 



2017 SkS Weekly Climate Change & Global Warming News Roundup #41

Posted on 14 October 2017 by John Hartz

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

Editor's Pick

Record Amazon fires stun scientists; sign of sick, degraded forests

Amazon Fire 

If climate change continues to worsen unchecked, and forest degradation continues unabated, then unstoppable Amazon mega-fires could be seen in this century; such fires would greatly increase the release of carbon into the atmosphere worsening climate change. Photo courtesy of IBAMA 
  • With the fire season still on-going, Brazil has seen 208,278 fires this year, putting 2017 on track to beat 2004’s record 270,295 fires. While drought (likely exacerbated by climate change) worsens the fires, experts say that nearly every blaze this year is human-caused.
  • The highest concentration of fires in the Amazon biome in September was in the São Félix do Xingu and Altamira regions. Fires in Pará state in September numbered 24,949, an astonishing six-fold increase compared with 3,944 recorded in the same month last year.
  • The Amazon areas seeing the most wildfires have also seen rapid change and development in recent years, with high levels of deforestation, and especially forest degradation, as loggers, cattle ranchers, agribusiness and dam builders move in.
  • Scientists warn of a dangerous synergy: forest degradation has turned the Amazon from carbon sink to carbon source; while globally, humanity’s carbon emissions are worsening drought and fires. Brazil’s rapid Amazon development deepens the problem. Researchers warn that mega-fires could be coming, unless trends are reversed. 

Record Amazon fires stun scientists; sign of sick, degraded forests by Sue Branford & Maurício Torres, Mongabay, Oct 11, 2017 



New research, October 2-8, 2017

Posted on 13 October 2017 by Ari Jokimäki

A selection of new climate related research articles is shown below.

Climate change

1. Comment on “Scrutinizing the carbon cycle and CO2 residence time in the atmosphere” by H. Harde

"As we will show, this alternative scheme is too simple, is based on invalid assumptions, and does not address many of the key processes involved in the global carbon cycle that are important on the timescale of interest. Harde (2017) therefore reaches an incorrect conclusion about the role of anthropogenic CO2 emissions."

2. A state-dependent quantification of climate sensitivity based on paleo data of the last 2.1 million years

"Finally, from data covering the last 2.1 Myr we show that — due to state dependency — the specific equilibrium climate sensitivity which considers radiative forcing of CO2 and land ice sheet (LI) albedo ... is larger during interglacial states than during glacial conditions by more than a factor two."

3. Heavy precipitation is highly sensitive to the magnitude of future warming

"We find that the frequency of annual heavy precipitation at a global scale increases in both 1.5 and 2 °C scenarios until around 2070, after which the magnitudes of the trend become much weaker or even negative."



SkS Analogy 10 - Bathtubs and Budgets

Posted on 12 October 2017 by Evan, jg

Tag Line

Adding 101 gallons to a 100-gallon bathtub causes it to overflow, even if added slowly.

Elevator Statement

No matter how slowly a bathtub is filled, adding more than 100 gallons of water to a 100-gallon bathtub causes it to overflow. This principle is clear, obvious, and one we encounter every time we take a bath.

Similar to the finite volume of a bathtub, Earth’s atmosphere has a finite volume. Because Earth’s atmosphere has a fixed volume, human emissions of greenhouse gases (GHGs) are increasing the atmospheric concentration of CO2, because we keep adding GHGs into this closed system, similar to running water into a bathtub.1 The concentration of CO2 does not depend on how rapidly we add GHGs to the atmosphere, but only on the total amount added.2 Lowering emission rates is important for improving the air quality in a large city, but carbon emission rates are meaningless for determining the global warming we will eventually experience due to a revved-up greenhouse effect: only the total amount emitted matters.3

Climate Science

The atmosphere has a budget of carbon it can accept to keep overall warming below a certain level, and the bathtub in this analogy is intended to be a visual representation of such a budget. Although scientists do not know with certainty how much the climate will warm for a doubling of CO2 (the so-called climate sensitivity), a climate sensitivity of 3°C/doubling of CO2 (see Ocean Time Lag)4 is consistent with the warming observed since the 1970’s, and is mid-range in the IPCC estimates that range from a low of 1.5 to a high of 4.5°C. Using a climate sensitivity of 3°C/doubling of CO2, a rough guide of the carbon budget corresponding to a particular level of warming is as follows5



Despite Trump, American companies are still investing in renewable energy

Posted on 11 October 2017 by John Abraham

After the election of Donald Trump, many of us in the climate and energy fields were rightfully fearful. What would happen to international agreements to cut greenhouse gases? What would happen to funding for climate research? What would happen to the green energy revolution?

In most instances, Trump is worse than we could have imagined. But in one special area, Trump may not matter. That is in the growth of corporate purchasing of renewable energy. It turns out there are factors that even Trump cannot stop that make choosing renewable energy an easy decision for many companies.

New evidence about the unstoppable renewable energy wave recently came out in a report that was released by Apex Clean Energy and the GreenBiz Group. These groups surveyed corporations to determine their future plans on renewable energy installation and adoption. They wanted to know whether these plans had changed in the past few years and what motivated their decisions to implement renewable energy strategies. The outcome of this survey is available here for people who want to read the entire document.

The groups surveyed 153 major corporations (both public and private), whose combined revenue was in excess of $250 million. Among these companies, 84% are “actively pursuing or considering purchasing renewable energy over the next 5-10 years.” Surprisingly, they found that 43% of the corporations intend to be more aggressive in their pursuit of renewable energy in the next two years. 87% of those actively pursuing renewable energy purchases stated that the election of Trump had no impact on their decision. 

In fact, 11% were more inclined to purchase renewable energy. Most surprising to me was that of the 128 companies that are actively pursuing or considering purchase of renewable energy over the next two years, all but 1 responded that they were “positive about either continuing forward or becoming more aggressive in their attempts to pursue renewables.” 



Analysis: How well have climate models projected global warming?

Posted on 10 October 2017 by Zeke Hausfather

This is a re-post from Carbon Brief.  For further details on this issue, see Dana's Lessons from Past Predictions series and book Climatology versus Pseudoscience.

Scientists have been making projections of future global warming using climate models of increasing complexity for the past four decades.

These models, driven by atmospheric physics and biogeochemistry, play an important role in our understanding of the Earth’s climate and how it will likely change in the future.

Carbon Brief has collected prominent climate model projections since 1973 to see how well they project both past and future global temperatures, as shown in the animation below. (Click the play button to start.)



Trump’s plan to bail out failing fossil fuels with taxpayer subsidies is perverse

Posted on 9 October 2017 by dana1981

The conservative philosophy of allowing an unregulated free market to operate unfettered often seems to fall by the wayside when the Republican Party’s industry allies are failing to compete in the marketplace. Trump’s Energy Secretary Rick Perry recently provided a stark example of this philosophical flexibility when he proposed to effectively pull the failing coal industry out of the marketplace and instead prop it up with taxpayer-funded subsidies.

Trump’s proposed coal bailout

The Trump administration has made no secret of its love for the coal industry. However, that industry has been losing badly in the free market, due largely to its inability to compete with cheaper natural gas and renewables. That was in fact the finding of Perry’s own Energy Department’s report, published just 3 months ago. The report also concluded:

Most of the common metrics for grid reliability suggest that the grid is in good shape despite the retirement of many baseload power plants … The power system is more reliable today due to better planning, market discipline, and better operating rules and standards

Perry’s new proposed rules directly contradict his department’s report, claiming “the resiliency of the electric grid is threatened by the premature retirements of these fuel-secure traditional baseload resources.” Perry tried to shift the goalposts from reliability to “resiliency” of the electric grid, essentially arguing that we need power plants that can store 90 days’ worth of fuel (i.e. huge piles of coal) to ensure that the grid remains “resilient.”

However, Perry also made the mistake of referencing the 2014 Polar Vortex to try and support this argument. The cold temperatures associated with that weather pattern caused electricity demand to spike, but as experts have noted, while wind energy produced above expectations during the Polar Vortex, coal power failed (emphasis added):

However, [Perry’s proposal] conveniently fails to mention that nearly 14 gigawatts (GW) of coal capacity was forced offline during the Polar Vortex, roughly 25 percent of all coal capacity in [the region]. 1.4 GW of nuclear was forced offline as well. Most of these generator outages were due to temperatures below the operating limit of power plant equipment ... Additional coal capacity was unavailable due to frozen coal piles.



2017 SkS Weekly Climate Change & Global Warming Digest #40

Posted on 8 October 2017 by John Hartz

Story of the Week... Editorial of the Week... El Niño/La Niña Update... Toon of the Week... SkS Spotlights... Video of the Week... Coming Soon on SkS... Poster of the Week... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

Science Says: Era of monster hurricanes roiling the Atlantic

Max Mayfield and Hurricane Wilma

In this Oct. 19, 2005 file photo, Max Mayfield, the former director of the hurricane center (now retired), draws a line showing one of the possible trajectories of Hurricane Wilma in Miami. It’s not just this year. The monster hurricanes Harvey, Irma, Maria, Jose and now Lee that have raged across the Atlantic are contributing to what appears to be the most active period for major storms on record. AP Photo/Alan Diaz)

It’s not just this year. The monster hurricanes Harvey, Irma, Maria, Jose and Lee that have raged across the Atlantic are contributing to what appears to be the most active period for major storms on record.

And the busiest part of hurricane season isn’t even over.

An analysis of 167 years of federal storm data by The Associated Press found that no 30-year period in history has seen this many major hurricanes, this many days of those whoppers spinning in the Atlantic, or this much overall energy generated by those powerful storms. 

Science Says: Era of monster hurricanes roiling the Atlantic by Seth Borenstein, AP, Oct 5, 2017



2017 SkS Weekly Climate Change & Global Warming News Roundup #40

Posted on 7 October 2017 by John Hartz

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

Editor's Pick

International concern as US moves to end clean power plan 

 US and Chinese presidents Barack Obama and Xi Jinping

US and Chinese presidents Barack Obama and Xi Jinping found common ground on climate change after the US announced the clean power plan (Pic: White House/Flickr) 

News that the Trump administration will move to repeal and replace the clean power plan (CPP) – a major initiative to cut emissions from the US electricity sector – has been met with concern overseas.

On Wednesday, the Reuters news agency reported on a document leaked from the Environment Protection Agency (EPA) outlining a plan to scrap the Obama-era measure.

It also called for input on a replacement policy that would reduce carbon emissions in fossil fuel power plants. Industry is reportedly lobbying for a weaker rule.

The policy underpinned the US commitment to the Paris Agreement, which Donald Trump says he wants to leave. It would also have had a real impact on the amount of carbon dioxide going into the atmosphere. By 2030, the clean power plan would have reduced power plant emissions in the world’s second biggest polluter by 32% below 2005 levels. 

International concern as US moves to end clean power plan by Karl Mathiesen, Climate Home,. Oct 4, 2017



New research, September 25 - October 1, 2017

Posted on 6 October 2017 by Ari Jokimäki

A selection of new climate related research articles is shown below.

Climate change

1. Diurnal Cycle Variability of Surface Temperature Inferred from AIRS data

" is found that the DTR of the surface (skin) temperature over the global Earth has a temporal small positive trend in the decade of the AIRS measurements indicating that the day temperatures grew slightly more rapidly than the night temperatures. A possible cause of the observed DTR increase is a decrease of the low cloud fraction at nighttime found for the same time period from the AIRS retrievals."

2. The influence of ice sheets on temperature during the past 38 million years inferred from a one-dimensional ice sheet–climate model

"We find that ice volume variability has a strong enhancing effect on atmospheric temperature changes, particularly in the regions where the ice sheets are located. As a result, polar amplification in the Northern Hemisphere decreases towards warmer climates as there is little land ice left to melt. Conversely, decay of the Antarctic ice sheet increases polar amplification in the Southern Hemisphere in the high-CO2 regime. Our results also show that in cooler climates than the pre-industrial, the ice–albedo feedback predominates the surface–height–temperature feedback, while in warmer climates they are more equal in strength."



Factcheck: Climate models have not ‘exaggerated’ global warming

Posted on 5 October 2017 by Zeke Hausfather

This is a re-post from Carbon Brief

A new study published in the Nature Geosciences journal this week by largely UK-based climate scientists has led to claims in the media that climate models are “wrong” and have significantly overestimated the observed warming of the planet.

Here Carbon Brief shows why such claims are a misrepresentation of the paper’s main results. In reality, the results obtained from the type of model-observation comparisons performed in the paper depend greatly on the dataset and model outputs used by the authors.

Much of the media coverage surrounding the paper, Millar et al, has focused on the idea that climate models are overestimating observed temperatures by around 0.3C, or nearly 33% of the observed warming since the late 1800s. For example, the Daily Mail reported:

According to these models, temperatures across the world should now be at least 1.3 degrees above the mid-19th century average, which is taken as a base level in such calculations. But the British report demonstrates that the rise is only between 0.9 and 1 degree.

Lead author Dr Richard Millar and his co-authors have pushed back against such media coverage, releasing a statement which says:

A number of media reports have asserted that our [study] indicates that global temperatures are not rising as fast as predicted by the Intergovernmental Panel on Climate Change (IPCC), and hence that action to reduce greenhouse gas emissions is no longer urgent. Both assertions are false. Our results are entirely in line with the IPCC’s 2013 prediction that temperatures in the 2020s would be 0.9-1.3 degrees above pre-industrial [levels].

[Carbon Brief’s guest post by Dr Millar earlier this week includes the paper’s key figures. Additionally, one of his co-authors, Prof Piers Forster, provides further reaction at the end of this article.]

Contrary to media claims, the study found that warming is consistent with the range of IPCC models, albeit a bit lower than the average of all the models.

Indeed, as Carbon Brief explains in detail below, the difference between models and observations turns out to depend largely on what climate model outputs and observational temperature series are used. The 0.3C value is based on a misinterpretation of the paper by the media and was not intended by the authors as an estimate of current model/observation temperature differences.



Global climate impacts of a potential volcanic eruption of Mount Agung

Posted on 4 October 2017 by Guest Author

Guest post by: 

Flavio Lehner ( and John Fasullo

National Center for Atmospheric Research, Boulder, CO, USA

An example of a stratovolcano eruption (note: not Mt. Agung). On July 13, 2015, the Operational Land Imager (OLI) on Landsat 8 took a close up of Mount Raung's summit caldera (on the Indonesian island of Java). Visible is afternoon cloud cover and an eruption plume. Image courtesy of NASA.

Recent weeks have seen an increase in the number of earthquakes happening below Mount Agung, a 9,944ft (3,031m) high volcano in eastern Bali, Indonesia. Authorities have evacuated nearly 50,000 people in the vicinity of the volcano in light of a potential eruption. In addition to concern for people’s lives and infrastructure, the tourism industry fears the potential for disrupted flight plans.

Mount Agung erupted last in 1963, killing over 1,000 people. As is common with large explosive eruptions, it also injected significant amounts of sulfur dioxide into the stratosphere (at least 16-18km above the surface). There, sulfur dioxide combined with water to form sulfuric acid aerosols. These aerosols reflect incoming solar radiation, causing cooling of the Earth’s climate. In fact, volcanic eruptions have been the most important external driver of interannual to decadal variability in global mean surface temperature for at least the past millennium1.



Inside the Experiment: Abrupt Change and Ice Cores

Posted on 3 October 2017 by greenman3610

This is a re-post from Yale Climate Connections.  Read the full post here.

Jørgen Peder Steffensen, of Denmark's Niels Bohr Institute, is one of the most experienced experts in ice core analysis, in both Greenland and Antarctica. Dr. Steffensen explained to videographer Peter Sinclair his concerns about possible abrupt climate changes.



Why the 97% climate consensus is important

Posted on 2 October 2017 by dana1981, John Cook

John Cook is a research assistant professor at the Center for Climate Change Communication at George Mason University, researching cognitive science.

Sander van der Linden is an Assistant Professor in Social Psychology, Director of the Cambridge Social Decision-Making Lab and a Fellow of Churchill College.

Anthony Leiserowitz is a Research Scientist and Director of the Yale Project on Climate Change at the School of Forestry and Environmental Studies at Yale University.

Edward Maibach is a University Professor and Director of Mason’s Center for Climate Change Communication.

Unfortunately, humans don’t have infinite brain capacity, so no one can become an expert on every subject. But people have found ways to overcome our individual limitations through social intelligence, for example by developing and paying special attention to the consensus of experts. Modern societies have developed entire institutions to distill and communicate expert consensus, ranging from national academies of science to the Intergovernmental Panel on Climate Change. Assessments of scientific consensus help us tap the collective wisdom of a crowd of experts. In short, people value expert consensus as a guide to help them navigate an increasingly complex and risk-filled world.

More generally, consensus is an important process in society. Human cooperation, from small groups to entire nations, requires some degree of consensus, for example on shared goals and the best means to achieve those goals. Indeed, some biologists have argued that “human societies are unable to function without consensus.” Neurological evidence even suggests that when people learn that they are in agreement with experts, reward signals are produced in the brain. Importantly, establishing consensus in one domain (e.g. climate science) can serve as a stepping stone to establishing consensus in other domains (e.g. need for climate policy).

The value of consensus is well understood by the opponents of climate action, like the fossil fuel industry. In the early 1990s, despite the fact that an international scientific consensus was already forming, the fossil fuel industry invested in misinformation campaigns to confuse the public about the level of scientific agreement that human-caused global warming is happening. As has been well-documented, fossil fuel companies learned this strategy from the tobacco industry, which invested enormous sums in marketing and public relations campaigns to sow doubt in the public mind about the causal link between smoking and lung cancer.

However, some academics have recently argued that communicators and educators should not inform the public about the strong scientific consensus on climate change. UK sociologist Warren Pearce and his colleagues recently published a commentary (and corresponding Guardian op-ed) arguing that communicating the scientific consensus is actually counter-productive. John Cook published a reply, which we summarize here.



2017 SkS Weekly Climate Change & Global Warming Digest #39

Posted on 1 October 2017 by John Hartz

Story of the Week... Toon 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...

September is the most energetic month for hurricanes ever recorded in the Atlantic

Hurricane Maria Sep 20, 2017 

Satellite image of Hurricane Maria making landfall on Puerto Rico on Sep 20, 2017 

The 2017 hurricane season has certainly been one for the record books. Whether it be Harvey’s scale-tipping rains, Irma’s off-the-chart winds, or the sheer number of storms that have spun up, this year is clearly anything but normal.

But how wacky has the weather in the tropics been? For that, meteorologists refer to a figure known as ACE, a measure of every hurricane’s energy put together during its life span. September produced the most ACE in any month on record in the Atlantic Ocean.

ACE, or Accumulated Cyclone Energy, is manifest in stirred-up oceans, steamy downpours, crackling lightning and ferocious winds. The force to instigate these nasty conditions is extracted from the roasting waters of the tropical Atlantic and Caribbean, and transformed into motion through a hurricane’s natural “heat engine.”

To quantify this measure, scientists take into account the strength of the winds within each and every storm, as well as their duration. ACE is calculated every six hours, and a running tally is kept for each storm so long as it sticks around. The measure does not take into account a storm’s size. 

September is the most energetic month for hurricanes ever recorded in the Atlantic by Matthew Cappucci, Capital Weather Gang, Washington Post, Sep 27, 2017



2017 SkS Weekly Climate Change & Global Warming News Roundup #39

Posted on 30 September 2017 by John Hartz

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

Editor's Pick

People Are Dying’: Puerto Rico Faces Daunting Humanitarian Crisis

As the full scope of Hurricane Maria's devastation emerges, leaders are calling for urgent help. Many of the risks were spelled out in a 2013 climate assessment.

Puerto Rico Aftermath of Hurricane Maria 

Hurricane Maria swept mud and debris down streets and into homes across the U.S. territory of Puerto Rico, home to 3.4 million people, about 44 percent of whom live below the poverty line. Credit: Hector Retamal/AFP/Getty Images

A public health crisis is unfolding in Puerto Rico following Hurricane Maria, as millions of people face a frightening array of urgent dangers, some of which may drag on for weeks or months.

Nearly one week after the storm hit, federal emergency response personnel struggled to make contact with remote communities and restore critical medical infrastructure.



New research, September 18-24, 2017

Posted on 29 September 2017 by Ari Jokimäki

A selection of new climate related research articles is shown below. The graphic is from Lamsal et al. (paper #32).

Climate change

1. Inconsistent subsurface and deeper ocean warming signals during recent global warming and hiatus

"In general, the global SDO has sequestered a significant amount of heat – about 3.50*1022 joules with trends of 0.59 W m−2 on average among the four datasets – during the recent hiatus, demonstrating widespread and significant warming signals in the global SDO." (SDO = Subsurface and Deeper Ocean.)

2. Enhanced Decadal Warming of the Southeast Indian Ocean during the Recent Global Surface Warming Slowdown

"The rapid Indian Ocean warming during the early-21th century was a major heat sink for the recent global surface warming slowdown. Analysis of observational data and ocean model experiments reveals that during 2003-2012 more than half of the increased upper Indian Ocean heat content was concentrated in the southeast Indian Ocean (SEIO), causing a warming “hotspot” of 0.8-1.2 K decade-1 near the west coast of Australia." ... "Large-ensemble climate model simulations suggest that this warming event was likely also exacerbated by anthropogenic forcing and thus unprecedentedly strong as compared to previous IPO transition periods."

3. Emission budgets and pathways consistent with limiting warming to 1.5°C

"If CO2 emissions are continuously adjusted over time to limit 2100 warming to 1.5°C, with ambitious non-CO2 mitigation, net future cumulative CO2 emissions are unlikely to prove less than 250GtC and unlikely greater than 540GtC. Hence, limiting warming to 1.5°C is not yet a geophysical impossibility, but is likely to require delivery on strengthened pledges for 2030 followed by challengingly deep and rapid mitigation."

4. More-Persistent Weak Stratospheric Polar Vortex States Linked to Cold Extremes

"Using hierarchical clustering, we show that over the last 37 years, the frequency of weak vortex states in mid to late winter (January and February) has increased which were accompanied by subsequent cold extremes in mid-latitude Eurasia. For this region 60% of the observed cooling in the era of Arctic amplification, i.e. since 1990, can be explained by the increased frequency of weak stratospheric polar vortex states, a number which increases to almost 80% when El Niño/Southern Oscillation (ENSO) variability is included as well."



Climate and energy are becoming focal points in state political races

Posted on 28 September 2017 by John Abraham

As soon as Donald Trump won the presidential election, people in the US and around the world knew it was terrible news for the environment. Not wanting to believe that he would try to follow through on our worst fears, we held out hope

Those hopes for a sane US federal government were misplaced. But they are replaced by a new hope – an emerging climate leadership at the state level and a continuation of economic forces that favor clean/renewable energy over dirty fossil fuels. In fact, it appears that some states are relishing the national and international leadership roles that they have undertaken. Support for sensible climate and energy policies is now a topic to run on in elections.

This change has manifested itself in American politics. One such plan stems from my home state, but it exemplifies work in other regions. I live in the state of Minnesota where we are gearing up for a gubernatorial election, which is where this plan comes from.

My state is well known as somewhat progressive, both socially and economically. The progressive policies resulted in a very strong 2007 renewable energy standard, which helped to reduce carbon pollution and create 15,000 jobs. 



Right-wing media could not be more wrong about the 1.5°C carbon budget paper

Posted on 27 September 2017 by dana1981

Last week, Nature Geoscience published a study suggesting that we have a bigger remaining carbon budget than previously thought to keep global warming below the 1.5°C aggressive Paris climate target. Many scientists quickly commented that the paper’s conclusion was based on some questionable assumptions, and this single study shouldn’t be blindly accepted as gospel truth.

Conservative media outlets did even worse than that. They took one part of the paper’s analysis out of context and grossly distorted its conclusions to advance their anti-climate agenda.

1.5°C might indeed be a geophysical impossibility

The study used the UK Met Office and Hadley Centre’s HadCRUT4 global temperature data set to conclude that so far we’ve warmed 0.93°C from the mid-1800s to 2015, compared to the Paris target of 1.5°C above pre-industrial temperatures. Several climate scientists immediately noted a problem here – HadCRUT4 excludes the Arctic region, which is the fastest-warming part of the planet. Hence it’s one of the least globally-representative temperature datasets. According to more globally-complete data sets like Berkeley Earth, the warming we’ve seen is closer to 1.1°C.

Defining “pre-industrial temperatures” is another issue. Humans caused some global warming prior to the mid-1800s; as one recent study showed, as much as 0.2°C.
A third problem discussed by climate scientists Stefan Rahmstorf at RealClimatei nvolves the way the study authors defined the budget itself. They looked at how much carbon will be emitted at the time we reach 1.5°C warming, but because of what’s known as the ‘thermal inertia’ of the oceans, and because sunlight-reflecting pollutants will fall out of the atmosphere as we shift away from dirty coal power, the planet will keep warming after that time.

If we take all these factors together, depending on how we decide to define “pre-industrial” in the Paris target, we may in fact already be committed to 1.5°C warming, and the headline conclusion that “the 1.5C warming limit is not yet a geophysical impossibility” may be incorrect.

But ultimately that’s a relatively unimportant point.



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