global warming

A study led by ISGlobal researchers has analysed how the loss of Arctic sea ice influences climate in isolation from other factors related to climate change. Their results, published in the journal Communications Earth and Environment, show that, on a time scale of decades, the loss of Arctic sea ice favours a drier climate in the southwestern United States -in particular in California-, especially in winter. This phenomenon would also affect the climate of Spain and Portugal, leading to wetter conditions in winter, although the effect is weaker.

The maximum number of artificial satellites that can safely orbit the Earth could be reduced due to the increase in greenhouse gas emissions of human origin, according to a modelling study. The increase in these gases may result in a reduction in the density of the planet's orbital space. Between 2000 and 2100, the carrying capacity of satellites between 200 and 1,000 kilometres altitude could be reduced by between 50 and 66%, estimates the study published in Nature Sustainability.

Research has analyzed how extreme heat influences the biological age of elderly populations, specifically in the United States. The study, published in Science Advances, used blood samples from more than 3,600 adults with an average age of 68 collected between 2010 and 2016. The team compared epigenetic aging trends with the number of days of extreme heat in the participants' places of residence. The models showed that more days of heat or long-term heat — over a period of one to six years — increased the biological age of the participants by more than two years.

Two papers published in Nature Climate Change analyse the possibility of exceeding the Paris Agreement targets of limiting warming to 1.5°C above pre-industrial temperatures. Both papers suggest that having exceeded this warming threshold by 2024 could indicate that we have entered a period of several decades with average global warming of 1.5 °C. According to the authors, rigorous climate mitigation efforts are needed to keep the Paris Agreement targets within reach.

As announced, the new US president, Donald Trump, has signed on his first day in office an executive order for the United States to withdraw from the Paris Agreement. This is the second time Trump has withdrawn his country from the signatory states of the most important climate change agreement, as he did in 2020.

The largest carbon balance report shows that carbon dioxide emissions have not yet peaked and are projected to reach 37.4 billion tonnes by 2024. In a briefing organised by SMC Spain, Pep Canadell, one of the people in charge of the Global Carbon Budget 2024, analysed these data and what Donald Trump's return as US president means for climate action in the framework of COP29 in Baku.

There are still no clear signs that global fossil carbon dioxide (CO₂) emissions have peaked, according to the 2024 Global Carbon Budget. The report - which is published in the journal Earth System Science Data in preprint format and will be launched at COP29 in Baku - estimates that these emissions will grow by 0.8% this year compared to 2023, to 37.4 billion tonnes of CO₂. If this rate continues, there is a 50% chance that global warming will exceed the 1.5°C limit in six years.

Next Monday sees the start of COP29 in Baku, the capital of Azerbaijan, a summit marked by Donald Trump's victory as president of the United States on Tuesday. His denial of climate change and his commitment to fossil fuels during his previous term in office will weigh down a meeting from which no major agreements are expected and from which experts are calling for greater ambition. 

Research published in Nature analyses future scenarios in which the 1.5°C temperature limit set in the Paris Agreement would be temporarily exceeded, assuming that temperatures could be lowered in the long term by reducing carbon dioxide emissions using different techniques. The authors stress that exceeding this threshold would have irreversible consequences for the Earth system in key areas such as biodiversity, sea level and carbon stocks. ‘Only rapid, short-term emission reductions are effective in reducing climate risks,’ they stress in the paper.

More frequent and severe wildfires increase the temperature of the exposed land surface one year after the fire, according to an analysis of forest satellite data collected from 2003 to 2016. In recent decades, large wildfires have doubled or tripled their average size in eastern Spain, Canada, and western United States, as noted in the research published in Nature. The authors call for consideration of these effects on surface temperature when managing forests.