Arctic Sea Ice September 2016 - Update

[ click on images to enlarge ]

On September 10, 2016, Arctic sea ice reached the second lowest extent measured by satellites since 1979, as the image on the right shows. Arctic sea ice took over second-lowest position with an extent of 4.137 million square km. This was 17,000 square km lower than the 2007 minimum, which was 4.154 million square km on September 18, 2007, according to NSIDC data.

Also note the purple line for 2010 on this image. In early September 2010, some people thought a low was reached (on September 12, 2010), but then a much lower extent was reached later (on September 21, 2010).

Arctic sea ice extent may well decline further over the coming days. The image on the right shows a temperature anomaly forecast for September 24, 2016. This gives an idea of the temperature anomalies that can be expected over the Arctic Ocean over the upcoming week. Temperature anomalies over the Arctic as a whole will be above 2 degrees Celsius for almost that entire period.

In conclusion, there is scope for further sea ice decline, for a number of reasons:
- high air temperatures over the Arctic Ocean
- warm river water runoff
- high temperatures of the water in the Arctic Ocean
- very thin and fractured sea ice
- high levels of greenhouse gases, especially methane

The danger is that, as temperatures of the water of the Arctic Ocean keep rising, heat will reach sediments at the bottom of the Arctic Ocean containing methane hydrates that are on the verge of destabilization. A small increase in temperatures could trigger huge abrupt release of methane from the seafloor of the Arctic Ocean.

The image below shows that on September 14, 2016, methane levels at 367 mb were as high as 2697 ppb and global mean methane level was as high as 1865 ppb.