Science Daily

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica's ice sheets. An international research team has now used sediments taken from the South Pacific to reconstruct the flow speed in the last 5.3 million years. Their data show that during glacial periods, the current slowed; during interglacials, it accelerated. Consequently, if the current global warming intensifies in the future, it could mean that the Southern Ocean stores less CO2 and that more heat reaches Antarctica.

Ground-based measuring devices and aircraft radar operated in the far northeast of Greenland show how much ice the 79 N-Glacier is losing. According to recent measurements, the thickness of the glacier has decreased by more than 160 meters since 1998. Warm ocean water flowing under the glacier tongue is melting the ice from below. High air temperatures cause lakes to form on the surface, whose water flows through huge channels in the ice into the ocean. One channel reached a height of 500 meters, while the ice above was only 190 meters thick.

Researchers sought to understand how diatoms -- microscopic, photosynthetic algae that make up an estimated 20 percent of global carbon sequestration and oxygen production -- are able to bloom in an ice-covered Lake Erie and how ice decline across the Great Lakes is impacting the algae.

When climate scientists look to the future to determine what the effects of climate change may be, they use computer models to simulate potential outcomes such as how precipitation will change in a warming world. Some scientists are also looking at something a little more tangible: coral.

In order to limit the increase in global average temperature to 1.5 C, it is essential to drastically reduce carbon dioxide emissions in the atmosphere. This would mean not exploiting most of the existing coal, conventional gas and oil energy resources in regions around the world, according to new research. The study presents the atlas of unburnable oil in the world, a world map designed with environmental and social criteria that warns which oil resources should not be exploited to meet the commitments of the Paris Agreement signed in 2015 to mitigate the effects of climate change.

The period that liquid water was present on the surface of Mars may have been shorter than previously thought. Channel landforms called gullies, previously thought to be formed exclusively by liquid water, can also be formed by the action of evaporating CO2 ice, according to a new study.

Emperor penguin populations have been exceedingly difficult to monitor because of their remote locations, and because individuals form breeding colonies on seasonal sea ice fastened to land (known as fast ice) during the dark and cold Antarctic winter. New research that incorporates very high-resolution satellite imagery with field-based validation surveys and long-term data has provided the first multi-year time series that documents emperor penguin global population trends.

Researchers have conducted the first large-scale observation and modeling study of northwest Greenland's Petermann Glacier. Their findings reveal the intrusion of warm ocean water beneath the ice as the culprit in the accelerated melting it has experienced since the turn of the century, and their computer predictions indicate that potential sea level rise will be much worse than previously estimated.

A comprehensive study of the floristic diversity of Agguttinni Territorial Park, Nunavut's newest and largest Territorial Park, has documented 141 vascular plant, 69 bryophyte, and 93 lichen species from this unique protected area on northern Baffin Island. Through a combination of extensive fieldwork in 2021 and examination of hundreds of existing herbarium specimens, the authors have documented species newly reported for Baffin Island and have crafted a biodiversity baseline important for park management and conservation.

Arctic sea ice is shrinking as the world continues to warm, and a new study may provide a better understanding of how the loss of this ice may impact daily weather in the middle latitudes, like the United States.

Will ice floating in the Arctic Ocean move faster or slower over the coming decades? The answer to this question will tell us whether marine transportation can be expected to get more or less hazardous. It might also have important implications for the rate of ice cover loss, which is hugely consequential for Northern Indigenous communities, ecosystems, and the global climate system. While observational data suggest the trend has been towards faster sea ice speeds, climate models project that those speeds will slow down during the summer season. This contrast has led to some questions around the plausibility of the model projections.

Scientists recently combined satellite data, field observations and sophisticated numerical modeling to paint a picture of how 22.45 million square kilometers of the Arctic will change over the next 80 years. As expected, the overall region will be warmer and wetter, but the details -- up to 25% more runoff, 30% more subsurface runoff and a progressively drier southern Arctic, provides one of the clearest views yet of how the landscape will respond to climate change.

While summer sea ice loss in the Arctic is inevitable, it can be reversed if the planet cools down, researchers say.

Most of the sunlight reaching the Arctic Ocean is reflected to space by sea ice, effectively shielding ocean ecosystems from sunlight. As the Arctic sea ice continues its downward trend, larger areas of the ocean become exposed to sunlight for longer periods, potentially allowing more primary production on the seafloor. However, according to a new study, this anticipated increase in primary production does not seem to be occurring uniformly across the Arctic Ocean.

Scientists found unexpected evidence the area of polynyas around Antarctica is increasing dramatically, and it follows an intriguing cycle, growing and shrinking roughly every 16 years.

Research unearthed new information to help scientists better understand circulation patterns of ocean water around glaciers. In the summers of 2014 and 2019, a group of pioneers in glacial research attached GPS devices to 13 icebergs and tracked hourly changes in their positions as they passed through Greenland's Ilulissat Icefjord toward the ocean. Study results showed circulation in the primary fjord is greatly affected by freshwater flow from connecting tributary fjords, which is critically important to consider in circulation models.

Glacier-fed streams are undergoing a process of profound change, according to scientists. This conclusion is based on the expeditions to the world's major mountain ranges by members of the Vanishing Glaciers project.

Massive volcanic events in Earth's history that released large amounts of carbon into the atmosphere frequently correlate with periods of severe environmental change and mass extinctions. A new method to estimate how much and how rapidly carbon was released by the volcanoes could improve our understanding of the climate response, according to an international team.

Global melting is prying the lid off methane stocks, the extent of which we do not know. A researcher has now discovered high concentrations of the powerful greenhouse gas in meltwater from three Canadian mountain glaciers, where it was not thought to exist -- adding new unknowns to the understanding of methane emissions from Earth's glaciated regions.

New research documents the fastest-known large-scale breakage along an Antarctic ice shelf. A 6.5-mile crack formed in 2012 over 5-and-a-half minutes, showing that ice shelves can effectively shatter -- though the speed is limited by seawater rushing in. The results help inform large-scale ice sheet models and projections of future sea level rise.