*Projections for the future still loom large*
The seas are creeping higher as the planet warms. But how high could they go?
Projections for the year 2100 range from inches to several feet, or even more.
The sub-tropical islands of Bermuda and the Bahamas are two seemingly unlikely places scientists have gone looking for answers. (more…)
*History of influence of industrial revolution hidden in glacial ice*
New clues about how Earth’s remote ecosystems have been influenced by the industrial revolution have been uncovered. Until now they were locked away, frozen in the ice of glaciers.
So say scientist Aron Stubbins of the Skidaway Institute of Oceanography and colleagues. (more…)
A new University of Colorado Boulder-led study appears to answer contentious questions about the onset and cause of Earth’s Little Ice Age, a period of cooling temperatures that began after the Middle Ages and lasted into the late 19th century.
According to the new study, the Little Ice Age began abruptly between A.D. 1275 and 1300, triggered by repeated, explosive volcanism and sustained by a self- perpetuating sea ice-ocean feedback system in the North Atlantic Ocean, according to CU-Boulder Professor Gifford Miller, who led the study. The primary evidence comes from radiocarbon dates from dead vegetation emerging from rapidly melting icecaps on Baffin Island in the Canadian Arctic, combined with ice and sediment core data from the poles and Iceland and from sea ice climate model simulations, said Miller. (more…)
A hemispherewide phenomenon – and not just regional forces – has caused record-breaking amounts of freshwater to accumulate in the Arctic’s Beaufort Sea.
Frigid freshwater flowing into the Arctic Ocean from three of Russia’s mighty rivers was diverted hundreds of miles to a completely different part of the ocean in response to a decades-long shift in atmospheric pressure associated with the phenomenon called the Arctic Oscillation, according to findings published in the Jan. 5 issue of Nature. (more…)
An international team of researchers, including physical oceanographers from the Woods Hole Oceanographic Institution (WHOI), has confirmed the presence of a deep-reaching ocean circulation system off Iceland that could significantly influence the ocean’s response to climate change in previously unforeseen ways.
The current, called the North Icelandic Jet (NIJ), contributes to a key component of the Atlantic Meridional Overturning Circulation (AMOC), also known as the “great ocean conveyor belt,” which is critically important for regulating Earth’s climate. As part of the planet’s reciprocal relationship between ocean circulation and climate, this conveyor belt transports warm surface water to high latitudes where the water warms the air, then cools, sinks, and returns towards the equator as a deep flow. (more…)
*Melting ice sheets contributed much more to rising sea levels than thermal expansion of warming ocean waters during the Last Interglacial Period, a UA-led team of researchers has found. The results further suggest that ocean levels continue to rise long after warming of the atmosphere levels off.*
Thermal expansion of seawater contributed only slightly to rising sea levels compared to melting ice sheets during the Last Interglacial Period, a University of Arizona-led team of researchers has found.
The study combined paleoclimate records with computer simulations of atmosphere-ocean interactions and the team’s co-authored paper is accepted for publication in Geophysical Research Letters. (more…)
Warming of the ocean’s subsurface layers will melt underwater portions of the Greenland and Antarctic ice sheets faster than previously thought, according to new University of Arizona-led research. Such melting would increase the sea level more than already projected.
The research, based on 19 state-of-the-art climate models, proposes a new mechanism by which global warming will accelerate the melting of the great ice sheets during this century and the next. (more…)
Global warming over the next 40 years will cut through Arctic transportation networks like a double-edged sword, limiting access in certain areas and vastly increasing it in others, a new UCLA study predicts.
“As sea ice continues to melt, accessibility by sea will increase, but the viability of an important network of roads that depend on freezing temperatures is threatened by a warming climate,” said Scott Stephenson, a UCLA graduate student in geography and the study’s lead author. (more…)
