Why Half a Degree Really Matters
By Tim Radford
Researchers now know the difference half a degree can make. They can tell you why 1.5°C warming would be better than a 2°C climb in average global temperatures, because even half a degree Celsius could mean greater extremes of heat, more overwhelming rainfall and longer spells of warm weather.
And they know all this because they've seen it happen in the recent past. There is enough evidence, they say, in the observational record for the last half century to underline the importance of even half a degree.
Scientists from Germany and Switzerland outline the argument and identify the evidence in the journal Nature Climate Change.
In the last two centuries, the ratio of carbon dioxide, the result of extravagant fossil fuel use since the Industrial Revolution, has risen from around 280 parts per million to 400 ppm, and average global temperatures have risen around 1°C during that time.
The researchers matched temperature and climate records for the years 1960 to 1979 and 1991 to 2010, a period when the thermometer averages climbed by a whole half a degree.
Significant changes
They found that the intensity of extreme rainfall had increased by nine percent over that period. The coldest winters were measurably less cold, and half of the global land mass had experienced changes of what they called "warm spell duration" of more than six days.
It is not that perceptible global warming made these extremes happen—extremes happen anyway—but the researchers think it made them more likely. By raising the temperature, humans loaded the climate dice.
"The hottest summer temperatures increased by more than 1°C in a quarter of global land areas, while the coldest winter temperatures warmed by more than 2.5°C," said Peter Pfleiderer, a scientist with the Potsdam Institute for Climate Impact Research and for Climate Analytics.
And his colleague Carl-Friedrich Schleussner said, "As we're moving increasingly outside of the range of natural climate variability, we have to expect that impacts on agriculture, human and biological systems will be more pronounced."
The Intergovernmental Panel on Climate Change has begun to prepare a special report on the impacts of a warming of 1.5°C, the Paris agreement target set by the world's nations in 2015.
There is no certainty that the world's nations can meet the Paris target and contain global warming, and limit climate change, because enough carbon dioxide has been emitted to take air temperatures over land to that level already.
The next decade could be critical, which is why researchers feel they need the evidence in as clear a form as possible.
"One of the pressing questions for scientists today is whether we know that limiting warming to 1.5°C instead of 2°C would make a difference in the future. We have to rely on climate models to predict the future, but given we now have observational evidence of around 1˚C warming, we can also look at the real life impacts this warming has brought," Schleussner said.
And the third signatory, Erich Fischer of ETH Zurich, said, "Communicating abstract quantities like differences in global mean temperature is difficult.
"With the warming the world has already experienced, we have an actual record of warming to study, and we can see very clearly that a difference of 0.5˚C of warming really does matter."
Reposted with permission from our media associate Climate News Network.
Santa Barbara Becomes First California City to Pass Resolution Against Offshore Oil and Gas Drilling
The Santa Barbara City Council approved a resolution Tuesday opposing new drilling off the California coast and fracking in existing offshore oil and gas wells. The resolution is the first in a new statewide campaign to rally local governments against proposals to expand offshore fossil fuel extraction in federal waters.
The vote—which makes Santa Barbara the first California city to oppose both fracking and new offshore drilling—follows President Trump's April 28 executive order urging federal agencies to expand oil and gas leasing in federal waters. The order could expose the Pacific Ocean to new oil leasing for the first time in more than 30 years.
Find Out What's in Your Tap Water
Starting Wednesday, the vast majority of Americans can learn about every potentially harmful chemical in their drinking water and what scientists say are the safe levels of those contaminants. The Environmental Working Group's (EWG) new national Tap Water Database is the most complete source available on the quality of U.S. drinking water, aggregating and analyzing data from almost 50,000 public water systems in all 50 states and the District of Columbia.
The organization has earned a reputation for ambitious data-mining research projects that shake up policy debates and consumer markets. EWG's online Farm Subsidy Database, listing millions of subsidy recipients, and its Skin Deep guide to more than 70,000 personal care products, draw tens of millions of visitors every year.
Are Corporate Ties Influencing Reuters Science Coverage?
By Stacy Malkan
Ever since they classified the world's most widely used herbicide as "probably carcinogenic to humans," a team of international scientists at the World Health Organization's (WHO) cancer research group have been under withering attack by the agrichemical industry and its surrogates.
In a front-page series, The Monsanto Papers, the French newspaper Le Monde described the attacks as "the pesticide giant's war on science," and reported, "to save glyphosate, the firm [Monsanto] undertook to harm the United Nations agency against cancer by all means."
#UtilitiesKnew, Too, Since 1968
The U.S. electric utility industry recognized decades ago that burning fossil fuels would lead to increased warming, yet later opposed efforts to shift away from coal, according to a new report.
The lengthy report from the Energy and Policy Institute uses reams of archival documents to demonstrate that utility industry representatives knew as far back as 1968 that burning fossil fuels could trigger "catastrophic effects" on the climate.
Sunoco Ordered to Temporarily Suspend Drilling on Pipeline Project
By Sharon Kelly
The Pennsylvania's Environmental Hearing Board ordered Sunoco Pipeline LP Tuesday to temporarily halt some types of work on a $2.5 billion pipeline project designed to carry 275,000 barrels a day of butane, propane and other liquid fossil fuels from Ohio and West Virginia, across Pennsylvania, to the Atlantic coast.
On July 19, three environmental groups presented Judge Bernard Labuskes, Jr. with documentation showing that the project had caused dozens of drilling fluid spills and other accidents between April and mid-June.
UK Bans All New Petrol and Diesel Cars by 2040
By Andy Rowell
The UK has followed France in banning the sale of new petrol and diesel cars by 2040, as part of its plan to tackle chronic air pollution in cities. The government has been coming under intense pressure to act, with an estimated 40,000 people dying prematurely a year from air pollution.
This Man Visited 27 National Monuments in 2 Weeks to Protect Them From Destruction
By Colleen Curry
People traveling across America today can, if they're lucky, pitch a tent in the same exact spot that early American explorers and map-makers Lewis and Clark did, amid the jagged rocks and sweeping plains of the Upper Missouri River Breaks in central Montana.
Brent Rose, a journalist and filmmaker who has been traveling around the U.S. in a van for two years, was one of the lucky ones.
Baby Orca Born in Captivity Dies at SeaWorld
Kyara, a killer whale born at SeaWorld San Antonio just three months ago, died Monday at the park, as reported in this video from Newsy. Kyara is the last orca to be born in captivity under the SeaWorld breeding program, which shut down in 2016.
In a statement, SeaWorld said the cause of death was "likely pneumonia" and that "Kyara had faced some very serious and progressive health issues over the last week."
