Guardian ‘There was a dramatic melting of Greenland’s ice sheet in the summer of 2019, researchers have confirmed, in a study that reveals the loss was largely down to a persistent zone of high pressure over the region. The ice sheet melted at a near record rate in 2019, and much faster than the average of previous decades. Figures have suggested that in July alone surface ice declined by 197 gigatonnes – equivalent to about 80 million Olympic swimming pools.
Now experts have examined the level of melting in more detail, revealing what drove it. Crucially, the team note, the high pressure conditions lasted for 63 of the 92 summer days in 2019, compared with an average of just 28 days between 1981 and 2010. A similar situation was seen in 2012, a record bad year for melting of the ice sheet. The team say the climate models of the Intergovernmental Panel on Climate Change (IPCC) have not taken into account such unusual conditions. If such high pressure zones become a regular annual feature, future melting could be twice as high as currently predicted, a result that could have serious consequences for sea level rise.’ Click here to read more
Glaciologists have described Thwaites as the “the most important glacier in the world, the riskiest glacier and even the ‘doomsday glacier. It already accounts for 4% of world sea level rise each year and it is melting faster than we thought.
World’s glaciers melting fast – EU Report
Excluding the Greenland and Antarctic Ice Sheets, glaciers cover approximately 706 600 km2 worldwide, with an estimated total volume of 170 000 km3. Melting glaciers have the potential to add significantly to sea level rise, but past best estimates of their contributions have been based on data from just a few hundred glaciers. This new study provides up-to-date estimates of changes in global glacier mass from 1961 to 2016, based on data from over 19 000 glaciers — these represent 19 regions of the world and around 10% of the glaciers in existence. The data comprised both in situ observations of changing glacier mass and information from various satellite missions, including those launched by the US, Japan and Germany. The scientists also benefited from advances in glacier measurement techniques and extrapolated their results to provide global estimates.