Mers et océans

The story of Greenland keeps getting greener—and scarier. A new study provides the first direct evidence that the center—not just the edges—of Greenland's ice sheet melted away in the recent geological past and the now-ice-covered island was then home to a green, tundra landscape.

There is increasing concern that the Atlantic Meridional Overturning Circulation (AMOC) may collapse this century with a disrupting societal impact on large parts of the world. Preliminary estimates of the probability of such an AMOC collapse have so far been based on conceptual models and statistical analyses of proxy data. Here, we provide observationally based estimates of such probabilities from reanalysis data. We first identify optimal observation regions of an AMOC collapse from a recent global climate model simulation. Salinity data near the southern boundary of the Atlantic turn out to be optimal to provide estimates of the time of the AMOC collapse in this model. Based on the reanalysis products, we next determine probability density functions of the AMOC collapse time. The collapse time is estimated between 2037-2064 (10-90% CI) with a mean of 2050 and the probability of an AMOC collapse before the year 2050 is estimated to be 59±17%.

Warning after intensification of storm aided by unusually hot ocean waters in much of Beryl’s path. Hurricane Beryl, which slammed into Texas on Monday after wreaking havoc in the Caribbean, was supercharged by “absolutely crazy” ocean temperatures that are likely to fuel further violent storms in the coming months, scientists have warned.

Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say

An intense heat wave gripping South and South-East Asia since late March comes as no surprise to leading meteorologists who have been warning of steadily rising temperatures in the Indian Ocean.

The law will come into force in national parks within two years and in all of the country’s marine protected areas by 2030

A long-term sea level dataset shows ocean surface heights continuing to rise at faster and faster rates over decades of observations. Global average sea level rose by about 0.3 inches (0.76 centimeters) from 2022 to 2023, a relatively large jump due mostly to a warming climate and the development of a strong El Niño. The total rise is equivalent to draining a quarter of Lake Superior into the ocean over the course of a year.

Elizabeth Kolbert on a record-breaking rise in global sea-surface temperatures, which suggests that scientists may not understand how fast the climate is changing.

Rapid ocean warming and unusually hot winter days recorded as human-made global heating combines with El Niño

Marine heat waves will become a regular occurrence in the Arctic in the near future and are a product of higher anthropogenic greenhouse-gas emissions, according to a study just released by Dr. Armineh Barkhordarian from Universität Hamburg's Cluster of Excellence for climate research CLICCS. Since 2007, conditions in the Arctic have shifted, as confirmed by data recently published in the journal Communications Earth & Environment. Between 2007 and 2021, the marginal zones of the Arctic Ocean experienced 11 marine heat waves, producing an average temperature rise of 2.2 degrees Celsius above seasonal norm and lasting an average of 37 days. Since 2015, there have been Arctic marine heat waves every year.

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.

Scientists now have a better understanding of the risks ahead and a new early warning signal to watch for.

Collapse in system of currents that helps regulate global climate would be at such speed that adaptation would be impossible

Anthropogenic emissions drive global-scale warming yet the temperature increase relative to pre-industrial levels is uncertain. Using 300 years of ocean mixed-layer temperature records preserved in sclerosponge carbonate skeletons, we demonstrate that industrial-era warming began in the mid-1860s, more than 80 years earlier than instrumental sea surface temperature records. The Sr/Ca palaeothermometer was calibrated against ‘modern’ (post-1963) highly correlated (R2 = 0.91) instrumental records of global sea surface temperatures, with the pre-industrial defined by nearly constant (<±0.1 °C) temperatures from 1700 to the early 1860s. Increasing ocean and land-air temperatures overlap until the late twentieth century, when the land began warming at nearly twice the rate of the surface oceans. Hotter land temperatures, together with the earlier onset of industrial-era warming, indicate that global warming was already 1.7 ± 0.1 °C above pre-industrial levels by 2020. Our result is 0.5 °C higher than IPCC estim

Jakarta’s subsidence crisis illustrates the conflation of two threats: global climatic sea-level rise and the local environmental crisis. It also sheds light on the city’s longstanding issues of urban flooding and chronic piped water supply shortages.

Plastic waste in aquatic environments may be severely disrupting the reproductive behavior of marine animals. 

Daily Sea Surface Temperature

ibrio are bacteria that cause an estimated 80,000 illnesses each year in the United States. About a dozen species of Vibrio are pathogenic to humans. V. parahaemolyticus causes the most infections in the United States, accounting for about 40% of reported cases of vibriosis, followed by V. alginolyticus, which accounts for about 20%. Most people with Vibrio infection have diarrhea. Some people might also have stomach cramping, nausea, vomiting, fever, and chills. One species, V. vulnificus, is known to cause life-threatening infections. About 150–200 V. vulnificus infections are reported to CDC each year and about one in five people with this infection die—sometimes within 1–2 days of becoming ill.

In March and April 2023, some Earth scientists began to point out that average sea surface temperatures had surpassed the highest levels seen in a key data record maintained by NOAA. Months later, they remain at record levels, with global sea surface temperatures 0.99°C (1.78°F) above average in July. That was the fourth consecutive month they were at record levels.

RealClimate: For various reasons I'm motivated to provide an update on my current thinking regarding the slowdown and tipping point of the Atlantic Meridional Overturning Circulation (AMOC). I attended a two-day AMOC session at the IUGG Conference the week before last, there's been interesting new papers, and in the light of that I have been changing