Veille 2.1

With current policies the Earth is on track to a warming of around 3 °C above preindustrial temperatures, a level of heat our planet has not seen for millions of years. Ecosystems, human society and infrastructure are not adapted to these temperatures. Due to non-linear effects, the impacts will be much more severe than just three times as bad as after 1 °C of warming. Land areas will continue to warm much more than the global average, many regions twice as much or even more. Extreme heat will become far more frequent and a major cause of human mortality, making large parts of the tropical land area essentially too hot to live. In addition, extreme rainfall and flooding, droughts, wildfires and harvest failures will increase in frequency and severity. The destructive power of tropical cyclones will also increase. Sea-level rise will accelerate further, and the destabilization of ice sheets will commit our descendants to loss of coastal cities and island nations. The risk of crossing devastating and irreversib

A crucial system of ocean currents may already be on course to collapse, according to a new report, with alarming implications for sea level rise and global weather — leading temperatures to plunge dramatically in some regions and rise in others. Using exceptionally complex and expensive computing systems, scientists found a new way to detect an early warning signal for the collapse of these currents, according to the study published Friday in the journal Science Advances. And as the planet warms, there are already indications it is heading in this direction.

With the help of the contingency concept, the article explores the reasons behind these surprises by introducing a new category of threats that complements the ones in the existing literature on surprise. It adds the concept of ‘known—corporally unknown’ threats to the list of known-unknowns, unknown-unknowns as a way to emsphasize the difference between abstract knowledge of ‘facts and figures’ (of e.g., global warming) and the acquiring of knowledge through personal, bodily experience (tangere) (of flooding and draughts). T

Without a phase out of fossil fuels, by 2100, 1 in 12 hospitals worldwide will be at high risk of total or partial shutdown from extreme weather events — a total of 16,245 hospitals. Without a phase out of fossil fuels, all of these 16,245 hospitals will require adaptation, where suitable. Even with this enormous investment, for many, relocation will be the only option.

Bonn and Geneva, 6 September 2023 (ECMWF and WMO) - Earth just had its hottest three months on record, according to the European Union-funded Copernicus Climate Change Service (C3S) implemented by ECMWF. Global sea surface temperatures are at unprecedented highs for the third consecutive month and Antarctic sea ice extent remains at a record low for the time of year.

As we mark 100 days until the COP28 UN climate summit, the urgency of addressing the climate crisis has never been more palpable. Global failures to mitigate emissions and adapt to the impacts continue to wreak havoc on the planet, and we’re seeing this in a range of ways. Unprecedented extreme weather events have occurred with frightening regularity in 2023. In March, over 500 people lost their lives when Cyclone Freddy struck Malawi. Last month, flooding in the Philippines caused by Typhoons Doksuri and Khanun displaced more than 300,000 people, and the recent wildfires that ravaged Hawaii – in part exacerbated by climate change – continue to make for distressing headlines. This list is likely to become even longer by the end of the year, when COP28 gets underway in the United Arab Emirates (UAE).

Heatwaves, wildfires and floods are just the ‘tip of the iceberg’, leading climate scientists say

It’s the middle of winter in South America, but that hasn’t kept the heat away in Chile, Argentina and surrounding locations. Multiple spells of oddly hot weather have roasted the region in recent weeks. The latest spell early this week has become the most intense, pushing the mercury above 100 degrees Fahrenheit, while setting an August record for Chile.

De extreme hittegolven deze maand in grote delen van de VS, Zuid-Europa en China zouden ‘vrijwel onmogelijk’ geweest zijn zonder de door de mens veroorzaakte klimaatverandering. Dat is de conclusie van het World Weather Attribution-initiatief (WWA).

Following a record hot June, large areas of the US and Mexico, Southern Europe and China experienced extreme heat in July 2023, breaking many local high temperature records.

The method used to conduct an attribution study consists of eight steps, described here. The first step is the selection of an extreme event to study. After selecting an extreme weather event to study, the first step is to define the event, which provides a framework for the study. Researchers determine the geographical boundaries of the most impacted area, the best index to quantify the meteorological extreme (eg. maximum temperature, average rainfall, etc), and the duration of the event.

Un guide sur l’attribution pour les journalistes - traduction

From deadly floods in Nigeria to devastating drought in Somalia, Africa has faced a run of severe – and sometimes unprecedented – extreme weather events since the start of 2022. But while the US hurricane season and 40C heat in the UK have captured headlines, many of Africa’s most extreme and life-changing weather events went largely unreported in global-north media.

The amount of heat accumulating in the ocean is accelerating and penetrating ever deeper, with widespread effects on extreme weather events and marine life, according to a new scientific review.

Can we talk about it now? I mean the subject most of the media and most of the political class has been avoiding for so long. You know, the only subject that ultimately counts – the survival of life on Earth. Everyone knows, however carefully they avoid the topic, that, beside it, all the topics filling the front pages and obsessing the pundits are dust. Even the Times editors still publishing columns denying climate science know it. Even the candidates for the Tory leadership, ignoring or downplaying the issue, know it. Never has a silence been so loud or so resonant.

Chief meteorologist says extreme temperatures ‘entirely consistent’ with human-induced climate crisis

Extreme event attribution aims to elucidate the link between global climate change, extreme weather events, and the harms experienced on the ground by people, property, and nature. It therefore allows the disentangling of different drivers of extreme weather from human-induced climate change and hence provides valuable information to adapt to climate change and to assess loss and damage. However, providing such assessments systematically is currently out of reach. This is due to limitations in attribution science, including the capacity for studying different types of events, as well as the geographical heterogeneity of both climate and impact data availability. Here, we review current knowledge of the influences of climate change on five different extreme weather hazards (extreme temperatures, heavy rainfall, drought, wildfire, tropical cyclones), the impacts of recent extreme weather events of each type, and thus the degree to which various impacts are attributable to climate change.

In March, the north and south poles had record temperatures. In May in Delhi, it hit 49C. Last week in Madrid, 40C. Experts say the worst effects of the climate emergency cannot be avoided if emissions continue to rise

À chaque événement météorologique extrême, c'est la même interrogation : le réchauffement climatique est-il responsable ? Pour répondre à cette question, un nouveau champ de la science se dessine : la science de l'attribution. Entretien avec Robert Vautard, membre du World Weather Attribution.

Depuis le début du mois de mars, l’Inde et le Pakistan étouffent sous une vague de chaleur prolongée inédite. Selon une étude (en anglais) conduite par le World Weather Attribution, le changement climatique l’aurait rendu trente fois plus probable. Pour quantifier l’effet de celui-ci, une équipe internationale de vingt-neuf chercheurs a analysé des données météorologiques et des simulations informatiques, afin de comparer le climat tel qu’il est aujourd’hui — soit 1,2 °C plus chaud qu’à la fin des années 1800, avec le climat antérieur à cette période.

Une nouvelle étude du World Weather Attribution, qui travaille sur l’attribution des événements climatiques extrêmes, estime que l’épisode de fournaise dans le sous-continent indien «aurait été extraordinairement rare» dans le passé.

Many are still missing after this month’s floods. Extreme weather is becoming more frequent, and it can be devastating

The Gulf Stream has weakened substantially in the past decades, as revealed by the latest data and new studies. Weather in the United States and Europe depends strongly on this ocean current, so it’s important we understand the ongoing changes and what they mean for our weather now and in the near future.

De klimaatimpact van reclames voor auto’s en vliegtuigreizen in de Europese Unie is vergelijkbaar met de totale uitstoot van België, stelt een studie door Greenpeace en het New Weather Institute. De organisaties pleiten voor een Europees verbod zoals dat bestaat voor tabaksreclame.

On Sunday, Kodiak Island in southern Alaska hit 67 degrees. That's warmer than it was in Southern California that same day. This set a record for the warmest December day in Alaska, according to the National Weather Service in Anchorage. Statewide temperature records in Alaska date back to 1953.

Warmer winters are happening across the globe, and can be drivers of catastrophic weather events and profound changes

The Australian Bureau of Meteorology has declared a La Niña weather event is under way, with modelling predicting it “will persist until the late southern hemisphere summer or early autumn 2022”.

We also asked about organisations’ risk response and approaches to planning. Our survey results support a picture of UK organisations that are taking steps to prepare for similar extreme weather, with the top three actions of organisations affected being capacity training or some form of knowledge transfer, investment in new technologies, and making an insurance claim. While just 16% of organisations reported having an adaptation plan, a considerable proportion (37%) said their organisation was planning to develop one.

Comment faire le lien entre des événements météorologiques extrêmes récents et le dérèglement climatique global causé par les activités humaines ? Entretien avec le chercheur au CNRS Robert Vautard, membre du réseau World Weather Attribution.