Glacial melting in Antarctica may become irreversible

Glacial melting in Antarctica may become irreversible

SOURCE: The Guardian DATE: July 9, 2019 SNIP: Antarctica faces a tipping point where glacial melting will accelerate and become irreversible even if global heating eases, research suggests. A Nasa-funded study found instability in the Thwaites glacier meant there would probably come a point when it was impossible to stop it flowing into the sea and triggering a 50cm sea level rise. Other Antarctic glaciers were likely to be similarly unstable. Recent research found the rate of ice loss from five Antarctic glaciers had doubled in six years and was five times faster than in the 1990s. Ice loss is spreading from the coast into the continent’s interior, with a reduction of more than 100 metres in thickness at some sites. The Thwaites glacier, part of the West Antarctic ice sheet, is believed to pose the greatest risk for rapid future sea level rise. Research recently published in the Proceedings of the National Academy of Sciences journal found it was likely to succumb to instability linked to the retreat of its grounding line on the seabed that would lead to it shedding ice faster than previously expected. Alex Robel, an assistant professor at the US Georgia Institute of Technology and the study’s leader, said if instability was triggered, the ice sheet could be lost in the space of 150 years, even if temperatures stopped rising. “It will keep going by itself and that’s the worry,” he said. Modelling simulations suggested extensive ice loss would start in 600 years but the researchers said it could occur sooner depending on the pace of global heating and nature of the...
Somali aid community faces up to a new reality of recurring drought

Somali aid community faces up to a new reality of recurring drought

SOURCE: Devex DATE: July 9, 2019 SNIP: If she were to meet someone from her past life, Halima Dahir Mahmoud is not sure they would recognize her. She’s lost weight and is constantly stressed. She was once a nomadic herder who would roam the Ethiopian countryside with her 200 sheep and goats, and 50 camels. Now she lives in a displacement camp on the outskirts of Somaliland’s capital city of Hargeisa. A few years ago, her animals started dying because of a regional drought. Eventually, there were none left. Her family left Ethiopia and walked 12 hours until they reached the displacement camp where they now live. Drought has burdened the region year after year since 2015, killing off livestock and crops. Globally, there has been an increase in the intensity and frequency of extreme weather events. In the Horn of Africa, scientists have linked climate change to frequent drought conditions. “We’ve faced five years of consecutive drought in this country. Livelihoods have collapsed,” said Mohamed Abdalle Hussein, director of administration and finance at the National Disaster Preparedness and Food Reserve Authority in Somaliland — a region that unilaterally declared independence from Somalia in 1991, although this is not internationally recognized. In the past, there was typically a buffer zone of good rainy seasons in between droughts that allowed people to recover and rebuild their assets, Hussein said. “Drought is a common disaster we’ve always faced, but the interval has changed. Before, it was a five to seven-year interval between [periods] when we experienced drought. Now that interval has decreased to one to two years,” he said. “If you...
Officials removed climate references from press releases

Officials removed climate references from press releases

SOURCE: E&E News DATE: July 8, 2019 SNIP: A March news release from the U.S. Geological Survey touted a new study that could be useful for infrastructure planning along the California coastline. At least that’s how the Trump administration conveyed it. The news release hardly stood out. It focused on the methodology of the study rather than its major findings, which showed that climate change could have a withering effect on California’s economy by inundating real estate over the next few decades. An earlier draft of the news release, written by researchers, was sanitized by Trump administration officials, who removed references to the dire effects of climate change after delaying its release for several months, according to three federal officials who saw it. The study, published in the journal Scientific Reports, showed that California, the world’s fifth-largest economy, would face more than $100 billion in damages related to climate change and sea-level rise by the end of the century. It found that three to seven times more people and businesses than previously believed would be exposed to severe flooding. “We show that for California, USA, the world’s 5th largest economy, over $150 billion of property equating to more than 6% of the state’s GDP and 600,000 people could be impacted by dynamic flooding by 2100,” the researchers wrote in the study. The release fits a pattern of downplaying climate research at USGS and in other agencies within the administration. While USGS does not appear to be halting the pursuit of science, it has publicly communicated an incomplete account of the peer-reviewed research or omitted it under President Trump. “It’s...
Breaching a ‘carbon threshold’ could lead to mass extinction

Breaching a ‘carbon threshold’ could lead to mass extinction

SOURCE: Phys.org and MIT DATE: July 8, 2019 SNIP: Daniel Rothman, professor of geophysics and co-director of the Lorenz Center in MIT’s Department of Earth, Atmospheric and Planetary Sciences, has found that when the rate at which carbon dioxide enters the oceans pushes past a certain threshold—whether as the result of a sudden burst or a slow, steady influx—the Earth may respond with a runaway cascade of chemical feedbacks, leading to extreme ocean acidification that dramatically amplifies the effects of the original trigger. This global reflex causes huge changes in the amount of carbon contained in the Earth’s oceans, and geologists can see evidence of these changes in layers of sediments preserved over hundreds of millions of years. Rothman looked through these geologic records and observed that over the last 540 million years, the ocean’s store of carbon changed abruptly, then recovered, dozens of times in a fashion similar to the abrupt nature of a neuron spike. This “excitation” of the carbon cycle occurred most dramatically near the time of four of the five great mass extinctions in Earth’s history. Scientists have attributed various triggers to these events, and they have assumed that the changes in ocean carbon that followed were proportional to the initial trigger—for instance, the smaller the trigger, the smaller the environmental fallout. But Rothman says that’s not the case. It didn’t matter what initially caused the events; for roughly half the disruptions in his database, once they were set in motion, the rate at which carbon increased was essentially the same. Their characteristic rate is likely a property of the carbon cycle itself—not the triggers,...
One climate crisis disaster happening every week, UN warns

One climate crisis disaster happening every week, UN warns

SOURCE: The Guardian DATE: July 7, 2019 SNIP: Climate crisis disasters are happening at the rate of one a week, though most draw little international attention and work is urgently needed to prepare developing countries for the profound impacts, the UN has warned. Catastrophes such as cyclones Idai and Kenneth in Mozambique and the drought afflicting India make headlines around the world. But large numbers of “lower impact events” that are causing death, displacement and suffering are occurring much faster than predicted, said Mami Mizutori, the UN secretary-general’s special representative on disaster risk reduction. “This is not about the future, this is about today.” This means that adapting to the climate crisis could no longer be seen as a long-term problem, but one that needed investment now, she said. “People need to talk more about adaptation and resilience.” Estimates put the cost of climate-related disasters at $520bn a year, while the additional cost of building infrastructure that is resistant to the effects of global heating is only about 3%, or $2.7tn in total over the next 20 years. Until now, most of the focus of work on the climate crisis has been on “mitigation” – jargon for cutting greenhouse gas emissions, and not to be confused with mitigating the effects of the climate crisis. The question of adapting to its effects has taken a distant second place, in part because activists and scientists were concerned for years that people would gain a false complacency that we need not cut emissions as we could adapt to the effects instead, and also because while cutting emissions could be clearly measured, the...