
-
Indian army says new exchange of gunfire with Pakistan
-
Epstein accuser Virginia Giuffre takes own life in Australia: family
-
Hundreds of buildings damaged, dozens injured in 6.3 Ecuador quake
-
India and Pakistan's Kashmir fallout hits economy too
-
Francis's funeral to be grand farewell to 'pope of the poor'
-
Pogacar faces defiant Evenepoel at Liege-Bastogne-Liege
-
Chelsea eye great escape against Barcelona in Women's Champions League
-
Iran, US to hold new round of high-level nuclear talks
-
'Energy and effort' pay off for Reds as Blues' woes continue
-
Albatross and closing birdie lift China's Liu to LPGA Chevron lead
-
On the horizon? Wave of momentum for high seas treaty
-
Developing countries should fast-track US trade deals: World Bank president
-
Grizzlies' Morant 'doubtful' for must-win game 4 v Thunder
-
Trump in Rome for pope funeral in first foreign trip of new term
-
Trump says Russia-Ukraine deal 'very close' after new Kremlin talks
-
US rookies lead PGA pairs event with McIlroy and Lowry in hunt
-
Trump tariff promises get a reality check
-
Warriors coach Kerr 'relatively optimistic' injured Butler will play game 3
-
Postecoglou hopes 'Stonecutter's Credo' can inspire Spurs
-
PSG lose unbeaten Ligue 1 record ahead of Arsenal showdown
-
Venezuela accuses El Salvador president of 'human trafficking'
-
Own goal takes Sundowns to African final against Pyramids
-
Scores of buildings damaged, 20 injured in Ecuador quake
-
US stocks extend rally as market eyes busy calendar next week
-
Pope's death triggers surge of disinformation he fought against
-
Rovanpera takes control of Rally Islas Canarias
-
Zelensky insists Crimea is Ukrainian as US envoy meets Putin
-
Patel and Mendis help Sunrisers beat Kings in Dhoni's 400th T20
-
Copa del Rey ref statements 'unacceptable': Real Madrid after boycotting final build-up
-
Insurance CEO's accused killer pleads not guilty to federal murder charges
-
FBI arrests Wisconsin judge for shielding undocumented migrant
-
Brazil ex-president Collor de Mello jailed for corruption
-
Zelensky insists Crimea 'belongs' to Ukraine as US envoy meets Putin
-
Real Madrid boycott Copa del Rey build-up over referee complaints
-
Trinidad and Tobago votes for parliament, PM, with opposition in lead
-
IMF chief hails 'constructive' Spring Meetings held under tariff uncertainty
-
Iran FM Araghchi in Oman ahead of nuclear talks with US
-
Dozens of buildings destroyed, 20 injured in Ecuador quake
-
Young Barca must 'enjoy' Real Madrid Copa final fight: Flick
-
Pakistan and India border closure separates families
-
Brazil's Bolsonaro 'stable' after post-surgery setback
-
Catholics in secular Cuba hail Francis as 'bridge'
-
US envoy Witkoff, Putin discuss 'possibility' of direct Russia-Ukraine talks
-
Community seeks answers after French school knife killing
-
German prosecutors seek jail terms in VW 'dieselgate' trial
-
Sabalenka makes winning start at Madrid Open
-
EU, US should de-escalate and negotiate trade deal: IMF Europe director
-
Russia accuses Ukraine of killing general in car bombing
-
Emery wants FA Cup glory and Champions League berth for Villa
-
Buildings destroyed, one injured in Ecuador quake

Study quantifies link between greenhouse gases, polar bear survival
Polar bears have long symbolized the dangers posed by climate change, as rising temperatures melt away the Arctic sea ice which they depend upon for survival.
But quantifying the impact of a single oil well or coal power plant on the tundra predators had eluded scientists, until now.
A new report published in the journal Science on Thursday shows it is possible to calculate how much new greenhouse gas emissions will increase the number of ice-free days in the bears' habitats, and how that in turn will affect the percentage of cubs that reach adulthood.
By achieving this level of granularity, the two authors hope to close a loophole in US law.
Although the apex carnivores have had endangered species protections since 2008, a long-standing legal opinion prevents climate considerations from affecting decisions on whether to grant permits to new fossil fuel projects.
"We have presented the information necessary to rescind the Bernhardt Memo," first co-author Steven Amstrup, a zoologist with Polar Bears International and the University of Wyoming, told AFP, referring to the legal caveat which was named after an attorney in former president George W. Bush's administration.
The memo stated it was beyond the scope of existing science to distinguish the impacts of a specific source of carbon emissions from the impacts of all greenhouse gasses since the beginning of the industrial age.
- Cub survival imperiled -
Polar bears rely heavily on the sea ice environment for hunting seals, traveling, mating and more.
When sea ice melts in summer, the apex carnivores retreat onto land or unproductive ice far from the shore, where they endure long stretches of fasting. These periods are growing longer as global temperatures rise.
A landmark paper published in Nature in 2020 was the first to calculate links between changes in the sea ice caused by climate and polar bear demographics.
Building on this work, Amstrup and Bitz established the mathematical relationships between greenhouse emissions and fasting days as well as cub survival, in 15 out of 19 of the polar bears' subpopulations, between 1979 and 2020.
For example, the world currently emits 50 billion metric tons of carbon dioxide or equivalent gasses into the atmosphere annually, and that is reducing the rate of cub survival by over three percentage points per year in the South Beaufort Sea subpopulation.
In healthy populations, cub survival during the first year of life is around 65 percent.
"You don't have to knock that down very far before you don't have enough cubs entering the next generation," said Amstrup.
In addition, the paper provides US policy makers the tools they need to quantify the impact of new fossil fuel projects slated to occur on public lands in the coming decades.
- Implications for other species -
Joel Berger, university chair of wildlife conservation at Colorado State University, praised the paper.
"Amstrup and Bitz render an incontrovertible quantitative link among (greenhouse gas) emissions, sea ice decline, fasting duration -- a physiological response to lost hunting opportunities for seals -- and subsequent polar bear demographics -- declining recruitment of young," said Berger, who was not involved in the research.
Beyond providing a potential policy solution to the legal loophole, the new research could have implications that reach far beyond polar bears, second co-author Cecilia Bitz, a climatologist at the University of Washington, told AFP.
Methods laid out in the paper can be adapted for other species and habitats, such as coral reefs, or Florida's Key deer.
"I really hope this stimulates a lot of research," Bitz said, adding she was already reaching out to new collaborators.
M.Thompson--AMWN