2015 SkS Weekly News Roundup #12B

Amazon rainforest soaking up less carbon as trees die young

The Amazon rainforest's ability to soak up greenhouse gases from the air has fallen sharply, possibly because climate change and droughts mean more trees are dying, an international team of scientists said on Wednesday.

The world's biggest rainforest has soaked up vast amounts of carbon dioxide. Plants use the heat-trapping gas to grow and release it when they rot or burn, but the report said that role in offsetting global warming may be under threat.

The study, of 321 plots in parts of the Amazon untouched by human activities, estimated the net amount of carbon dioxide absorbed by the forest had fallen by 30 percent, to 1.4 billion tonnes a year in the 2000s from 2.0 billion in the 1990s.

"Forest growth has flatlined over the last decade," lead author Roel Brienen of the University of Leeds told Reuters of the findings in the journal Nature. At the same time "the whole forest is living faster - trees grow faster, die faster." 

Amazon rainforest soaking up less carbon as trees die young - study by Alister Doyle, Reuters, Mar 18, 2015


Annual greenhouse gas emissions from forests drop by a quarter

Yearly carbon emissions from the world's forests have dropped by more than 25 percent in the last 15 years, a U.N. agency said on Friday.

The decrease in annual emissions, which cause global warming, is largely due to slowing rates of global deforestation, the Food and Agriculture Organisation (FAO) reported.

Forests hold about three quarters as much carbon as the atmosphere and preserving them is crucial for combating climate change.

"Deforestation and forest degradation increase the concentration of greenhouse gases in the atmosphere, but forest and tree growth absorbs carbon dioxide, the main greenhouse gas emissions," FAO director-general Jose Graziano da Silva said in a statement.

Emissions from deforestation decreased to 2.9 Gigatonnes of carbon dioxide from 3.9 Gigatonnes between 2001 and 2015, the FAO said.

Annual greenhouse gas emissions from forests drop by a quarter, U.N. says by Chris Arsenault, Thomson Reuters Foundation, Mar 20, 2015


Australia's farmers challenged by climate change

From tasteless carrots to sunburned apples, a new report by two University of Melbourne researchers paints a challenging picture for Australia's agricultural sector and the impacts of climate change in the decades to come.

Through the examination of 55 food commodities and a breakdown of the ways each of the country's multiple climate regions will be affected by climate change, the study concludes the quality of beef, chicken and even kangaroo will suffer.

The biggest challenge to come from climate change is a hotter, drier country. And how Australia responds might present a road map for agriculture elsewhere as the Earth's climate warms.

Australia's Farmers Challenged by Climate Change by Brittany Patterson, Scientific American/ClimateWire, Mar 19, 2015


China, U.S. may be moving closer to a climate deal

A U.S. envoy for climate change said Friday that China and the U.S. are working more closely than ever ahead of a conference this year in Paris that raises hopes for a global plan to cut greenhouse emissions. 

Special Envoy Todd Stern told reporters in Beijing that he still expects hard negotiations between many countries in advance of the U.N. summit. But he told reporters there's "a greater level of convergence on some very important structural issues" compared to the months before the last major U.N. climate summit, which ended without a significant agreement in 2009. 

With China emitting more greenhouse gases than any other country, and the U.S. a distant second, many are watching if the two countries can agree to a plan before the Paris meeting. 

"I think we're on the same page on some issues, not every issue probably," Stern said of the U.S. and China. "But we are working I think in a closer and more cooperative basis than we ever have before."

China, U.S. May Be Moving Closer To A Climate Deal by Jack Lang, AP/The Huffington Post, Mar 20, 2015


Coastal development exposes billions to swelling seas

While residents in Vanuatu are still battling flash floods caused by a devastating tropical cyclone last week, a study says coastal population growth may make storm threats from the sea a global crisis within a few decades.

In a paper published recently in the journal PLOS ONE, a team of researchers from several Western institutes estimated the number of people living in low-elevation coastal zones, as well as the scale of the population at risk from one-in-100-year storm surge events, by using scenario-based projections.

Their findings show that even under the lowest growth assumptions, the global population in low-elevation coastal zones could rise by more than 40 percent, from 625 million in 2000 to 879 million in 2030. By 2060, the researchers say, more than a billion people worldwide could be living in those flood-prone areas.

Among them, 411 million people could be affected by extreme flooding by 2060, the study notes. By contrast, this figure was 189 million in 2000.

Coastal Development Exposes Billions to Swelling Seas by Coco Liu, ClimateWire/Scientific American, Mar 20, 2015


FactCheck: is global warming intensifying cyclones in the Pacific?

“It’s very clear global warming is intensifying cyclones in the Pacific.” – Greens Leader Chistine Milne, comments to reporters, March 17, 2015.

Christine Milne’s statements on global warming linked the devastation wreaked by Cyclone Pam in Vanuatu last weekend with climate change.

But while there is very real possibility that there is a causal relationship between cyclone behaviour and anthropogenic global warming, most climate scientists and meteorologists are hesitant to attribute any single event such as an extreme intensity tropical cyclone to global warming. This is because we know that the globe has experienced such events for many thousands of years.

The key to understanding whether global warming is causing a change in the behaviour of tropical cyclones is to look at the trends, usually over as many years as possible.

FactCheck: is global warming intensifying cyclones in the Pacific? by Jonathan Nott & Kevin Walsh, The Conversation, Mar 19, 2015


Fossil fuels are way more expensive than you think

A new paper published in Climatic Change estimates that when we account for the pollution costs associated with our energy sources, gasoline costs an extra $3.80 per gallon, diesel an additional $4.80 per gallon, coal a further 24 cents per kilowatt-hour, and natural gas another 11 cents per kilowatt-hour that we don’t see in our fuel or energy bills.

The study was done by Drew Shindell, formerly of Nasa, now professor of climate sciences at Duke University, and Chair of the Scientific Advisory Panel to the Climate and Clean Air CoalitionShindell recently published research noting that aerosols and ozone have a bigger effect on the climate in the northern hemisphere, where humans produce more of those pollutants.

Fossil fuels are way more expensive than you think by Dana Nuccitelli, Climate Consensus - The 97%, The Guardian, Mar 19, 2015


Mitch McConnell’s dangerous new climate extremism: “A travesty of responsible leadership”

Mitch McConnell is going all in on his promise “do everything [he] can to try to stop” the EPA.

The Kentucky senator, who said last year that he feels a “deep responsibility” to thwarts the implementation of the agency’s Clean Power Plan, is now reaching “far beyond….[his] official reach and authority” to do so, directly appealing to state governors to refuse to comply with them.

In a letter sent Thursday to the National Governors Association, McConnell wrote that he has “serious legal and policy concerns” regarding the proposed rule, which aims to cut emissions from new coal-fired power plants 30 percent below 2005 levels by 2030. Building off the argument he first laid out in an editorial earlier this month, he claims that the EPA is going far beyond its legal authority, and that the rule is likely to be struck down by the courts.

Mitch McConnell’s dangerous new climate extremism: “A travesty of responsible leadership” by Lindsay Abrams, Salon, Mar 20, 2015


Obama to order cuts in Federal greenhouse gas emissions

President Obama will sign an executive order on Thursday to cut the federal government’s greenhouse gas emissions, a White House official said, his latest use of presidential power to address the root causes of climate change.

Having failed during his first term to push a cap-and-trade bill through Congress, Mr. Obama has begun a systematic effort to regulate pollution through the existing Clean Air Act, advancing new rules on emissions from cars and trucks, power plants and oil and gas wells.

Obama to Order Cuts in Federal Greenhouse Gas Emissions by Julie Hirschfeld Davis, New York Times, Mar 19, 2015


Overpumping of groundwater is contributing to global sea level rise

Pump too much groundwater and wells go dry – that’s obvious.

But there is another consequence that gets little attention as a hotter, drier planet turns increasingly to groundwater for life support.

So much water is being pumped out of the ground worldwide that it is contributing to global sea level rise, a phenomenon tied largely to warming temperatures and climate change.

Overpumping of groundwater is contributing to global sea level rise by Tom Knudson, Reveal, Mar 17, 2015


Scientists: Ted Cruz's climate theories are a "Load of Claptrap"

Last night, Sen. Ted Cruz (R-Texas), a probable candidate for the GOP presidential nomination, shared his thoughts about climate change with late-night host Seth Meyers (video above). Here's what he said:

CRUZ: I just came back from New Hampshire where there's snow and ice everywhere. And my view actually is simple. Debates on this should follow science and should follow data. And many of the alarmists on global warming, they've got a problem because the science doesn't back them up. And in particular, satellite data demonstrate for the last 17 years there's been zero warming, none whatsoever. It's why, you remember how it used to be called global warming, and then magically the theory changed to climate change?

MEYERS: Sure.

CRUZ: The reason is it wasn't warming. But the computer models still say it is, except the satellites show it's not.

We totally agree with his point that debates about climate "should follow science and should follow data." Right on! But according to Kevin Trenberth, a leading climate scientist at the National Center for Atmospheric Research, everything else in Cruz's quote is "a load of claptrap…absolute bunk."

Scientists: Ted Cruz's Climate Theories Are a "Load of Claptrap" by Tim McDonnell, Mother Jones, Mar 18, 2015


Ted Cruz goes full Orwell

n case you haven’t heard, Sen. Ted Cruz (R-Texas) is not a fan of reality.

The reality of science, that is. He has a history of saying global warming–denying talking points and used some of his political power just this past week to pressure NASA into downplaying its role in measuring the effects of global warming on the planet.

Earlier this week, Cruz went on Late Night With Seth Meyers, and they discussed the issue. What Cruz said, in its entirety, is what comes out of the south end of a north-facing bull. Watch:

Ted Cruz goes full Orwell by Phil Plait. Bad Astronomy. Slate, Mar 19, 2015


Two months in and 2015 is record warm

We may only be two months into 2015, but already the year is burning up the charts, setting up the possibility that it could topple 2014’s newly minted record for hottest year.

Together, January and February were the warmest such period on record, according to global data released Wednesday by the National Oceanic and Atmospheric Administration. With an El Niño (albeit a weak one) in place, there’s potential for that warmth to stick around and elevate temperatures for more of the year. 

Two months in and 2015 is record warm by Andrea Thompson, Climate Central, Mar 18, 2015


World could have 40 percent water shortfall by 2030, UN warns

The world could suffer a 40 percent shortfall in water in just 15 years unless countries dramatically change their use of the resource, a U.N. report warned Friday. 

Many underground water reserves are already running low, while rainfall patterns are predicted to become more erratic with climate change. As the world's population grows to an expected 9 billion by 2050, more groundwater will be needed for farming, industry and personal consumption.

The report predicts global water demand will increase 55 percent by 2050, while reserves dwindle. If current usage trends don't change, the world will have only 60 percent of the water it needs in 2030, it said.

World Could Have 40 Percent Water Shortfall By 2030, UN Warns by Katy Daigle, AP/The Huffington Post, Mar 20, 2015

Posted by John Hartz on Saturday, 21 March, 2015


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