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Showing posts from May, 2017

Arctic Warming - Update May 2017

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The image below illustrates how much and how fast oceans are warming on the Northern Hemisphere. Trend points at 1.5°C warmer NH oceans in 2025. Shaded area covers seasonal fluctuations and natural variability. As ocean warming continues, prospects for the sea ice in the Arctic are grim. Warmer water is melting the sea ice from below. The image on the right shows ever less sea ice volume in the Arctic, reflecting huge thinning of the sea ice over the years. As the sea ice gets thinner, it becomes ever more prone to break up in pieces that will melt quicker (as more surface area becomes exposed to heat from the atmosphere and heat from the water). [ images from:  Arctic Sea Ice May 2017 ] Moreover, with more open water, stronger waves and winds can develop, increasing the chances that sea ice will melt and get pushed out of the Arctic Ocean. El Niño looks set to strike again this year and the Arctic looks set to be hit much stronger than the rest of the world, as illustrated by the ima

Earthquake east of Greenland triggers methane releases

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An earthquake with a magnitude of M 4.5 on the Richter scale hit the seafloor 204 km East of Nord, Greenland, on May 8, 2017 at 04:48:53 (UTC) . Location: 81.684°N 5.076°W. Depth: 10.0 km. The inset shows that methane levels over 1950 ppb (magenta color) were recorded on the morning of May 8, 2017, by two satellites. This is a reminder that earthquakes can destabilize methane hydrates, which can hold huge amounts of methane in sediments at the seafloor of the Arctic Ocean. As temperatures keep rising, snow and ice on Greenland and Svalbard keeps melting, taking away weight from the surface, making that isostatic rebound can increasingly trigger earthquakes on the faultline that crosses the Arctic Ocean. Methane releases have followed earthquakes in the Arctic before, e.g. see this 2016 post , illustrating the danger of potentially huge methane releases in case of larger earthquakes in the Arctic. Why is methane so important again? Below follow some images from the methane page .  Over

Abrupt Warming - How Much And How Fast?

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How much could temperatures rise? As the image shows, a rise of more than 10°C (18°F) could take place, resulting in mass extinction of many species, including humans . How fast could such a temperature rise eventuate? As above image also shows, such a rise could take place within a few years. The polynomial trend is based on NASA January 2012-February 2017 anomalies from 1951-1980, adjusted by +0.59°C to cater for the rise from 1750 to 1951-1980. The trend points at a 3°C rise in the course of 2018, which would be devastating. Moreover, the rise doesn't stop there and the trend points at a 10°C rise as early as the year 2021. Is this polynomial trend the most appropriate one? This has been discussed for years, e.g. at the Controversy Page , and more recently at  Which Trend Is best? The bottom part of above image shows the warming elements that add up to the 10°C (18°F) temperature rise. Figures for five elements may be overestimated (as indicated by the ⇦ symbol) or underestimate

Arctic Sea Ice May 2017

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Last year, the Arctic was some 3.5°C warmer than it was at the start of the Industrial Revolution. Was this 3.5°C a spike or was it part of a trend pointing at even higher temperature anomalies this year and the following years? Above image shows NASA annual mean 64°N-90°N land-ocean temperature anomalies from 1951-1980, with +0.59°C added for the rise from 1750 to 1951-1980. A polynomial trend is added (based on 1880-2016 data), pointing at 4.5°C anomaly by 2019. Will the Arctic keep warming over the coming years in line with this trend? Let's have a look at what affects temperatures in the Arctic most, specifically Ocean Heat, Sea Ice, Land Temperatures and Emissions. 1. Ocean Heat Warmer Oceans on the Northern Hemisphere will contribute strongly to warming in the Arctic. Here's a graph showing a trend pointing at continued warming of the oceans on the Northern Hemisphere. Will oceans keep warming like that, in particular the North Atlantic? The Coriolis force keeps pushing