Understanding Sea Level Rise, p4: ice sheet dynamics and (13) melting feedbacks – a background to 21st century SLR acceleration

In 2016 two influential new publications raised the possibility of a rapid acceleration of sea level rise in the 21st century – to ±2 metres (DeConto & Pollard) or more (2-5m, Hansen et al). In this background article we take … Continue reading

Understanding Sea Level Rise, p3: it’s about timescales, speed of change & carbon budget – world aims for 29-55m sea level rise

In our previous article of the series we’ve looked at an overview of global sea level rise forecasts for the year 2100 – and seen that these forecasts have a very large spread, and also seem to increase with time … Continue reading

Largest known sea level rise took less than 350 years

Ocean level rise is known as one of the most disquieting effects of global warming, with more than three billion people living on the coast or less than 200 kilometres land inward and one tenth of the world population living … Continue reading

Amount of deep cold Antarctic bottom water decreasing over last decades

Antarctic bottom water

A layer of Antarctic Bottom Water colder than 0ºC (Credit: NOAA)

Scientists have found a large reduction in the amount of the coldest deep ocean water, called Antarctic Bottom Water, all around the Southern Ocean using data collected from 1980 to 2011.

These findings, in a study now online, will likely stimulate new research on the causes of this change.

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New NRC report on the state of the polar regions

GlacierThe U.S. National Research Council has just released a synthesis of reports from thousands of scientists in 60 countries who took part in the International Polar Year (IPY) 2007-08, the first in over 50 years to offer a benchmark for environmental conditions and new discoveries in the polar regions.

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Carbon dioxide’s climate effects confirmed: temperatures followed rising CO2 levels during last deglaciation

There has been much speculation about what exactly caused the end of the last ice age 10,000 years ago. Some say the Earth’s orbital changes were the cause, others say it was an increase in atmospheric CO2. But although a … Continue reading

2 degrees warmer climate in late Pliocene meant 12-32 meters higher sea levels

That would likely mean that also the official UN climate goal of limiting the average world temperature rise to no more than 2 degrees Celsius – a target linked to 450 ppm CO2 equivalent stabilisation scenarios (practically ambitious, theoretically weak) … Continue reading