Global surface warming enhanced by weak Atlantic overturning circulation

Palaeoceanographic records indicate that abrupt cooling of Northern Hemisphere during deglacial periods are linked to weakening of the Atlantic Meridional Overturning Circulation (AMOC). However, a  new article published in Nature argues that during a weak state of the AMOC, ocean heat is released to the atmosphere increasing the global surface temperature. This study further suggests that during... Continue Reading →

Antarctica and the Southern Ocean in 2070, under low and high emissions scenarios

A team of experts in biology, oceanography, glaciology, geophysics, climate science and policy, analyzed the potential impacts of two different future scenarios of carbon emissions, RCP2.6 (low emission & strong action) and RCP 8.5 (high emission & weak action), on Antarctica and the Southern Ocean. The team assessed key systems including  global average air temperature; Antarctic contribution... Continue Reading →

Antarctic ice sheet lost 2,720 ± 1,390 billion tonnes of ice between 1992 and 2017

A team of scientists leading the ice sheet mass balance inter-comparison exercise (IMBIE) combined satellite observations of the Antarctic ice sheet, its changing volume, flow and gravitational attraction with modelling of its surface mass balance from 1992 to 2017.  Their report, recently published in Nature, showed that the Antarctic ice sheet lost 2,720 ± 1,390 billion tonnes of... Continue Reading →

Antarctic ice shelf disintegration triggered by sea ice loss and ocean swell

Understanding the causes of recent catastrophic ice shelf disintegrations is a crucial step towards improving coupled models of the Antarctic Ice Sheet and predicting its future state and contribution to sea-level rise. An overlooked climate-related causal factor is regional sea ice loss. Here we show that for the disintegration events observed (the collapse of the... Continue Reading →

Man-made nutrient pollution could make coral reefs more vulnerable to ocean acidification

A team of scientists from California State University and University of Hawaii carried out a series of laboratory experiments adding nitrate and phosphate to aquariums that contain the coral reef community (corals, seaweeds and dead reef rubble). Their experiments showed that in nutrient polluted seawater, the calcification by coral reefs became less effective disrupting the relationship between... Continue Reading →

Sustained climate warming drives declining marine biological productivity

In the Southern Ocean, nutrient-rich North Atlantic Deep Water upwells to the surface, and the northward surface water sinks at mid-depth (as Subantarctic Mode Water and Antarctic Intermediate Water) and transports nutrients into the low-latitude thermocline. According to a recent article appeared in Science, climate model simulations under RCP 8.5 scenario project that the Antarctic... Continue Reading →

Antarctic volcanic eruption linked to the onset of the most rapid global climate change during the end of the last ice age

Cold and dry glacial-state climate conditions persisted in the Southern Hemisphere until approximately 17.7 ka, when paleoclimate records show a largely unexplained sharp, nearly synchronous acceleration in deglaciation. Detailed measurements in Antarctic ice cores document exactly at that time a unique, ∼192-y series of massive halogen-rich volcanic eruptions geochemically attributed to Mount Takahe in West... Continue Reading →

Hurricane Harvey links to ocean heat content and climate change adaptation

While hurricanes occur naturally, human‐caused climate change is supercharging them and exacerbating the risk of major damage. Here, using ocean and atmosphere observations, we demonstrate links between increased upper ocean heat content due to global warming with the extreme rainfalls from recent hurricanes. Hurricane Harvey provides an excellent case study as it was isolated in... Continue Reading →

Meridional overturning circulation conveys fast acidification to the deep Atlantic Ocean posing a severe threat to cold-water coral habitats.

Increasing atmospheric carbon dioxide concentrations are increasing the acidity of the oceans and reducing carbonate-ion concentrations, making it difficult for corals to maintain their calcium carbonate skeletons. This paper reports a roughly 40 per cent reduction in the transport of carbonate ions to the deep North Atlantic ocean since preindustrial times, with implications for cold-water... Continue Reading →

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