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The climate science behind this year’s wildfires and powerful storms

by Scott Pelley, 60 Minutes


Highlights

  • In 1988, NASA scientist James Hansen discovered that man made climate change would lead to a global rise in temperatures by the year 2020
  • “Career fires” or fire events that firefighters would likely only see once in their career, can typically burn up to 50,000 acres and are happening yearly in California
  • Though Hansen predicted climate changes three decades ago, he hoped that governments would have taken action:

“Well, if we don’t change anything, then we’re going to continue to see more and more of these extreme regional events because the physics is quite simple. As you add more greenhouse gases to the atmosphere, you increase the heating of the surface. So, at the times and places where it’s dry you get more extreme droughts. The fire seasons become longer. The fires burn hotter. But at the times and places where it’s wet, you get more evaporation of the water. And you get warmer, moist air, which provides greater rainfall. And it’s the fuel for storms.”

  • Many serious climate change effects such as mega-drought and melting ice sheets are occurring at a faster rate than what scientists previously predicted 
  • Hanson believes the best way to stop climate change would be to reduce all emissions to zero in order to allow the ocean and forests to sequester excess carbon
  • Another method Hanson suggests is taxing fossil fuels in order to make clean alternatives more cost-effective

Scientists are increasingly warning that to avoid catastrophic impacts from climate change, the world’s governments must implement massive reductions of warming emissions and begin a drawdown of greenhouse gases (GHG) from the atmosphere over the decade ahead.  For a safe and healthy future for all, endorse the Climate-Safe California Platform to implement scalable solutions that can reverse the climate crisis.


Read More: https://www.cbsnews.com/news/western-wilfires-record-temperatures-california-60-minutes-2020-10-04/

Timothy M. Lenton et al. (2008): Tipping elements in the Earth's climate system. In: Proceedings of the National Academy of the Sciences. February 2008, doi:10.1073/pnas.0705414105

Nine ‘tipping points’ that could be triggered by climate change

by Carbonbrief.org


Highlights

  • While climate records are being routinely broken, the cumulative impact of these changes could also cause fundamental parts of the Earth system to change dramatically and irreversibly. These “tipping points” are thresholds where a tiny change could push a system into a completely new state.
  • In some cases, there is evidence that once the system has jumped to a different state, then if you remove the climate forcing, the climate system doesn’t just jump back to the original state – it stays in its changed state for some considerable time, or possibly even permanently.
  • The nine tipping points discussed include: 1. Shutdown of the Atlantic Meridional Overturning Circulation
    2. West Antarctic ice sheet disintegration
    3. Amazon rainforest dieback
    4. West African monsoon shift
    5. Permafrost and methane hydrates
    6. Coral reef die-off
    7. Indian monsoon shift
    8. Greenland ice sheet disintegration
    9. Boreal forest shift
  • This is not an exhaustive list – there are other parts of the Earth system that have the potential to display tipping point behavior.
  • Human society may also have “tipping points” that favor climate action.

The Climate Center’s rapid decarbonization campaign uses a timeline based on the latest scientific findings and supports achieving carbon neutrality by 2030.


Read more: https://www.carbonbrief.org/explainer-nine-tipping-points-that-could-be-triggered-by-climate-change

Record hit for most ice to melt in Antarctica in one day, data suggests: “we are in a climate emergency”

by Kashmira Gander, News Week

The record in recent decades for the highest level of ice to melt in Antarctica in one day was reached on Christmas Eve, data suggests.

Around 15 percent of the continent’s surface melted on Monday, according to the Global Forecast System (GFS) by the National Centers for Environmental Prediction (NCEP). The data comes from the Modèle Atmosphérique Régional (MAR), a model used for meteorological and climatic research.

Read more: https://www.newsweek.com/record-hit-ice-melt-antarctica-day-climate-emergency-1479326?utm_medium=Social&utm_source=Twitter#Echobox=1577452266

After a rough year, farmers and Congress are talking about climate solutions

by Georgina Gustin, InsideClimate News

As millions of acres of American farmland sat under historic floodwaters this spring, a remarkable pattern began to emerge.

Even among fields that sat side-by-side, with the same crops and the same soil type, researchers and farmers noticed that some bounced back faster than others.

What made the difference?

The fields that were slow to drain and remained waterlogged longer had been farmed conventionally—tilled, left bare and unplanted over the winter. The fields that drained quickly and were ready for sowing hadn’t been tilled in years and had been planted every winter with cover crops, like rye and clover, which help control erosion, improve soil health and trap carbon in the soil.

Read more: https://insideclimatenews.org/news/26122019/agriculture-climate-change-flood-recovery-sustainable-farming-cover-crops-2019-year-review

‘Bleak’ U.N. Report on a Planet in Peril Looms Over New Climate Talks

  • Deeper and faster cuts are now required
  • Global greenhouse gas emissions have grown by 1.5 percent every year over the last decade. To stay within relatively safe limits, emissions must decline sharply, by 7.6 percent every year, between 2020 and 2030.
  • Even if every country fulfills its current pledges under the Paris Agreement — and many, including the United States, Brazil and Australia, are currently not on track to do so — the Emissions Gap Report found average temperatures are on track to rise by 3.2 degrees Celsius from the baseline average temperature at the start of the industrial age.
  • The International Energy Agency recently singled out the proliferation of sport utility vehicles, noting that the surge of S.U.V.s, which consume more gasoline than conventional cars, could wipe out much of the oil savings from a nascent electric-car boom.

By Semini Sengupta Read full NYTimes article here

With world leaders gathering in Madrid next week for their annual bargaining session over how to avert a climate catastrophe, the latest assessment issued by the United Nations said Tuesday that greenhouse gas emissions are still rising dangerously.

“The summary findings are bleak,” said the annual assessment, which is produced by the United Nations Environment Program and is formally known as the Emissions Gap Report. Countries have failed to halt the rise of greenhouse gas emissions despite repeated warnings from scientists, with China and the United States, the two biggest polluters, further increasing their emissions last year.

The result, the authors added, is that “deeper and faster cuts are now required.”

As if to underscore the gap between reality and diplomacy, the international climate negotiations, scheduled to begin next week, are not even designed to ramp up pledges by world leaders to cut their countries’ emissions. That deadline is still a year away….

….Separately, the World Meteorological Organization reported on Monday that emissions of three major greenhouse gases — carbon dioxide, methane and nitrous oxide — have all swelled in the atmosphere since the mid-18th century.

“We are sleepwalking toward a climate catastrophe and need to wake up and take urgent action,” said Alden Meyer, director of policy and strategy at the Union of Concerned Scientists, on a phone call with reporters Tuesday after the publication of the report….

….There are many ways to reduce emissions: quitting the combustion of fossil fuels, especially coal, the world’s dirtiest fossil fuel; switching to renewable energy like solar and wind power; moving away from gas- and diesel-guzzling cars; and halting deforestation….

….A number of countries around the world, including Canada and Norway, have made plans to reduce emissions at home while expanding fossil-fuel production for sale abroad, that report noted….

 

Why ranches, cattle, and meat-eating may play a role in fighting climate change.

by Lynne Curry, New Food Economy

As if the beef industry didn’t already have a bad rap, Brazil’s farmers have reportedly set the Amazon on fire to create more grazing land for the country’s booming beef industry. They are part of a global stampede to meet demand in developing markets—even as ruminant livestock, with cattle at the top of the list, take the heat for agriculture’s nearly 25 percent share of annual greenhouse gas (GHG) emissions worldwide.

Emissions related to agriculture are a primary cause of the current climate crisis—and, as major consumers of beef, Americans carry a large share of the blame. Although the American diet has shifted away from beef toward chicken, we still eat four times as much beef per capita, on average, as the rest of the world.

Read more: https://newfoodeconomy.org/climate-change-eat-less-meat-plant-based-impossible-burger-regenerative-ranching/

The IPCC global warming report spares politicians the worst details

by Bob Ward, The Guardian

A report by the Intergovernmental Panel on Climate Change confirms the enormous wisdom that governments showed in Paris in December 2015, when they agreed to the goal of “pursuing efforts” to limit global warming to 1.5C.

The report’s summary for policymakers paints a sobering picture of the potentially terrible impacts of allowing global mean surface temperature to rise by 2C compared with pre-industrial levels: more extreme weather, sea level riseand ocean acidification, with detrimental effects on wildlife, crops, water availability and human health.

Read more: https://amp.theguardian.com/commentisfree/2018/oct/08/world-leaders-climate-change-ipcc-report

99% of these sea turtles were born girls. Scientists suspect climate change is why

by Sean Rossman, USA Today

Researchers suggest a generation of sea turtles in the Great Barrier Reef were born mostly female because they were nested in warmer areas, raising concerns global warming might threaten the species.

The study, published Monday in the journal Current Biology, found 99.8% of green sea turtles near adulthood and originating from the northern — and warmer — part of the Great Barrier Reef were born female. A slightly younger group of juvenile turtles was found to be 99.1.% female.

“It was surprising and we were not expecting it at all,” said co-author Camryn Allen of the Joint Institute for Marine and Atmospheric Research in Honolulu, Hawaii. “We didn’t expect it to be that extreme.”

The study analyzed more than 400 turtles and was conducted by researchers from the U.S. National Oceanic and Atmospheric Administration (NOAA), as well as the Queensland Department of Environment and Heritage Protection in Australia.

The lopsided gender split, the authors point out, could cause the population to collapse, or the species to go extinct, unless efforts are made to lower nesting temperatures.
In the southern part of the Great Barrier Reef, where sand temperatures are cooler, females still outpaced males, but by far less. The study found juvenile and subadult turtles were 67.8% and 64.5% female, respectively.

The northern Great Barrier Reef, the site of the overwhelming female population, has one of the largest populations of green sea turtles in the world, the study said. It has a population of about 200,000 nesting females.

A shift of just a few degrees can have big impacts on sex outcomes in sea turtles. Sea turtle gender is dependent on the incubation temperature while a turtle is an embryo, a characteristic common in some reptiles. Cooler temperatures produce more males in sea turtles, while warmer temperatures produce more females. The temperature which produces the perfect ratio of half females and half males serves as the “pivotal temperature” marker. Researchers found temperatures in nesting spots in the northern Great Barrier Reef consistently skewed higher than the pivotal temperature since the 1990s. The juvenile and subadult groups were born within the past two decades.

The study shows the female percentages have increased in the northern Great Barrier Reef. Of the older adult-sized turtles analyzed, 86.8% were female, the study said.

“These results suggest that increased sand temperatures affect the sex ratios of the (northern Great Barrier Reef) population such that virtually no male turtles are now being produced from these nesting beaches,” the study said. “Our findings add another dimension to the growing body of evidence that increasing temperatures are broadly affecting (Great Barrier Reef) ecosystems.”

The question now, said co-author Michael Jensen, a research scientist working for NOAA, is how the turtles adapt to the temperatures. Instead of nesting in the heat of summer, Jensen said, turtles could nest earlier or later in the year when it’s cooler. They also could find cooler places to store their eggs.

But it can take generations to adapt, and that could be a long time for this sampling of turtles, which reach maturity at roughly 25 years old. That means in just a few generations, temperatures might increase by several degrees.

“Our study raises new concerns over the immediate threats of climate change to sea turtle populations,” the study read. “We need to learn more about how (temperature-dependent sex determination) species cope with rapid climate change.”

source: https://www.usatoday.com/story/news/nation-now/2018/01/09/99-these-sea-turtles-were-born-girls-global-warming-blame/1017020001/?csp=