Fires set stage for irreversible forest losses in Australia

Fires set stage for irreversible forest losses in Australia

SOURCE: AP DATE: January 19, 2020 SNIP: Heat waves and drought have fueled bigger and more frequent fires in parts of Australia, so far this season torching some 40,000 square miles (104,000 square kilometers), an area about as big as Ohio. With blazes still raging in the country’s southeast, government officials are drawing up plans to reseed burned areas to speed up forest recovery that could otherwise take decades or even centuries. But some scientists and forestry experts doubt that reseeding and other intervention efforts can match the scope of the destruction. The fires since September have killed 28 people and burned more than 2,600 houses. Before the recent wildfires, ecologists divided up Australia’s native vegetation into two categories: fire-adapted landscapes that burn periodically, and those that don’t burn. In the recent fires, that distinction lost meaning — even rainforests and peat swamps caught fire, likely changing them forever. Flames have blazed through jungles dried out by drought, such as Eungella National Park, where shrouds of mist have been replaced by smoke. “Anybody would have said these forests don’t burn, that there’s not enough material and they are wet. Well they did,” said forest restoration expert Sebastian Pfautsch, a research fellow at Western Sydney University. “I’m expecting major areas of (tree) loss this year, mainly because we will not have sufficient seed to sow them,” said Owen Bassett of Forest Solutions, a private company that works with government agencies to re-seed forests by helicopter following fires. In both Australia and western North America, climate experts say, fires will continue burning with increased frequency as warming temperatures and drier weather...
UN Warns of Extreme Weather Ahead After Declaring Hottest Decade in Recorded History

UN Warns of Extreme Weather Ahead After Declaring Hottest Decade in Recorded History

SOURCE: Science Alert DATE: January 16, 2020 SNIP: The past decade has been the hottest on record, the UN said Wednesday, warning that the higher temperatures were expected to fuel numerous extreme weather events in 2020 and beyond.​ The World Meteorological Organization, which based its findings on analysis of leading international datasets, said increases in global temperatures had already had dire consequences, pointing to “retreating ice, record sea levels, increasing ocean heat and acidification, and extreme weather”. WMO said its research also confirmed data released by the European Union’s climate monitor last week showing that 2019 was the second hottest year on record, after 2016. “Unfortunately, we expect to see much extreme weather throughout 2020 and the coming decades, fuelled by record levels of heat-trapping greenhouse gases in the atmosphere,” WMO chief Petteri Taalas said. The UN agency said that average global temperatures during both the past five-year (2015-2019) and 10-year (2010-2019) periods were the highest ever recorded. Since more than 90 percent of excess heat is stored in the world’s oceans, their heat content is a good way to quantify the rate of global warming, WMO said. Conservationists said the UN agency’s findings were to be expected. “It is no surprise that 2019 was the second hottest year on record – nature has been persistently reminding us that we have to pick up the pace,” said Manuel Pulgar-Vidal, leader of WWF’s global climate and energy practice, calling for dramatic measures to halt the warming...
Huge ‘hot blob’ in Pacific Ocean killed nearly a million seabirds

Huge ‘hot blob’ in Pacific Ocean killed nearly a million seabirds

SOURCE: The Guardian DATE: January 16, 2020 SNIP: A million seabirds died in less than a year as a result of a giant “blob” of hot ocean water off the coast of New Zealand, according to new research. A study released by the University of Washington found the birds, called the common murre, probably died of starvation between the summer of 2015 and the spring of 2016. Most dead seabirds never wash ashore, so while 62,000 dead or dying murres were found along the coasts of Alaska, Washington, Oregon and California, researchers estimate the total number is closer to 1 million. Alaska saw the most birds wash up. In Prince William Sound in southern Alaska, more than 4,500 bird carcasses were found every kilometer, or 0.62 miles. The blob stems from a years-long severe marine heatwave, believed to be caused by an anticyclone weather system that first appeared in 2013. A weather phenomenon known as El Niño accelerated the warming temperatures beginning in 2015 and, by 2016, the rising heat resulted in water temperatures nearly 11F (6C) above average. Anticyclones form when a mass of air cools, contracts and becomes more dense, increasing the weight of the atmosphere and the surface air pressure. Heat maps at the time showed a massive red blob growing, spanning more than 380,000 sq miles (1 million sq km). That’s nearly 1.5 times the size of Texas or four times larger than New Zealand. The study found that the murres mostly likely starved to death. The seabird must eat half its body weight to survive, but food grew scarce amid intense competition from other...
Ocean Warming Is Speeding Up, with Devastating Consequences, Study Shows

Ocean Warming Is Speeding Up, with Devastating Consequences, Study Shows

SOURCE: Inside Climate News DATE: January 14, 2020 SNIP: The world’s oceans are warming at a rapidly increasing pace, new research shows, and the heat is having devastating effects on marine life and intensifying extreme weather. Last year, the oceans were warmer than any time since measurements began over 60 years ago, according to a study published Monday in the journal Advances in Atmospheric Sciences. While global surface temperature measurements go back farther in time, the measurement of ocean heat content is considered one of the most effective ways to show how fast Earth is warming because more than 90 percent of the heat trapped by greenhouse gases goes into the oceans. The new study, the first to analyze ocean temperatures for 2019, was based on two independent data sets and used a new way of filling data gaps to measure ocean temperatures going back to the 1950s. When the scientists compared ocean temperature data from the last three decades (1987-2019) to the three decades before that (1955-1986), they found the rate of warming had increased 450 percent, “reflecting a major increase in the rate of global climate change.” Measured by a common energy unit used in physics, the oceans absorbed 228 sextillion joules of heat in the past 25 years. That’s equivalent to adding the energy of 3.6 billion Hiroshima-size atom bomb explosions to the oceans, said the study’s lead author, Lijing Cheng, with the International Center for Climate and Environmental Sciences at the Institute of Atmospheric Physics. The warming of the oceans has widespread effects. It causes marine heat waves that kill fish and coral reefs, fuels...
New climate models suggest Paris goals may be out of reach

New climate models suggest Paris goals may be out of reach

SOURCE: Phys.Org DATE: January 14, 2020 SNIP: New climate models show carbon dioxide is a more potent greenhouse gas than previously understood, a finding that could push the Paris treaty goals for capping global warming out of reach, scientists have told AFP. Developed in parallel by separate teams in half-a-dozen countries, the models—which will underpin revised UN temperature projections next year—suggest scientists have for decades consistently underestimated the warming potential of CO2. Vastly more data and computing power has become available since the current Intergovernmental Panel on Climate Change (IPCC) projections were finalised in 2013. “We have better models now,” Olivier Boucher, head of the Institut Pierre Simon Laplace Climate Modelling Centre in Paris, told AFP, adding that they “represent current climate trends more accurately”. The most influential projections from government-backed teams in the US, Britain, France and Canada point to a future in which CO2 concentrations that have long been equated with a 3C world would more likely heat the planet’s surface by four or five degrees. For more than a century, scientists have puzzled over a deceptively simple question: if the amount of CO2 in the atmosphere doubles, how much will Earth’s surface warm over time? The resulting temperature increase is known as Earth’s “climate sensitivity”. That number has been hard to pin down due to a host of elusive variables. Whether oceans and forests, for example, will continue to absorb more than half of the CO2 emitted by humanity is hard to predict. “How clouds evolve in a warmer climate and whether they will exert a tempering or amplifying effect has long been a major source...
Native Species or Invasive? The Distinction Blurs as the World Warms

Native Species or Invasive? The Distinction Blurs as the World Warms

SOURCE: Yale e360 DATE: January 14, 2020 SNIP: Across the warming globe, a mass exodus of tens of thousands of species is transforming the distribution of biodiversity — and challenging fundamental tenets in conservation policy and science. Are policymakers, land managers, and conservationists prepared? In recent years, scientists have documented countless species shifting their ranges toward the poles, higher into the mountains, and deeper into the seas in response to the changing climate. Deciduous shrubs of willow, birch, and alder have spread into the low Arctic tundra. Brightly colored tropical parrotfish and rabbitfish have arrived in the temperate kelp forests of the eastern Mediterranean. Elkhorn corals from the Caribbean now sprout in thickets off the coast of Galveston, Texas. The trend is expected to continue as the climate crisis deepens, with species that societies rely upon for a wide range of economic, cultural, and recreational value shifting their ranges to survive. “The entire trajectory of natural capital, from aesthetic to economic,” says University of Florida wildlife ecologist Brett Scheffers, “is going to be moving.” The coming exodus, Scheffers and other scientists say, will require a transformation in the way we think about wildlife management and conservation — and a reevaluation of the traditional native-alien dichotomy that has governed it. For decades, conservation biology has characterized the movement of species into new habitats as potential invasions of alien species with the capacity to threaten local ecosystems and already resident species, leading to the formulation of policies to reflexively repel the newcomers. This approach, and its underlying classification of wild species as either “native” (and thus worthy of protections) or “alien”...