Tag Archives: DMSP

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The sea ice in the Arctic is at maximum extent in February and retreats through to mid September.

This movie shows the Arctic sea ice extent from 1 Feb to 25 July 2017. The data come from the DMSP SMMI sensor, and it shows the retreat of the sea ice as summer progresses.

You can see from the NSDIC that Arctic sea ice extent is tracking close to the 2012 minimum, and about ~1.6 million km2 below 1981-2010 median.

Arctic sea ice extent to 26 July 2017 from NSIDC.
Arctic sea ice extent to 26 July 2017 from NSIDC.

To see where the sea ice "isn't" you can see the gif I made for a post last week.

The mean Arctic sea ice for the years 1989-93 on 27 July, the sea ice concentration on 27 July 2017 and the difference between the two data sets. Blue shades imply more sea ice and reds imply decreased sea ice compared with the mean. The original data come from the DMSP SMMI data set at the NSIDC.
The mean Arctic sea ice for the years 1989-93 on 27 July, the sea ice concentration on 27 July 2017 and the difference between the two data sets. Blue shades imply more sea ice and reds imply decreased sea ice compared with the mean. The original data come from the DMSP SMMI data set at the NSIDC.

In that post I said

Things that stand out for me are the virtually open water in the Barents and Kara Seas.

~6-8 weeks of melt to go...

Today the NASA Earth Observatory Website has published a beautiful image from 29 June 2017 of Hudson Bay in a post called Lingering Sea Ice on Hudson Bay.

Lingering Sea Ice on Hudson Bay
Lingering Sea Ice on Hudson Bay. Image NASA Earth Observatory.

To the untrained eye the sea ice in the bay looks like cloud, but if you look at the still from the movie above on the same day, the sea ice is clear.

Hudson Bay 28 June 2017
Hudson Bay 28 June 2017

The NASA blog post talks about how polar bears were hunting in this sea ice.

 

Sea ice is still relatively low in both the the Arctic spring and Antarctic autumn. A geographical perspective always helps so here is the status of the sea ice concentration 23 April 2017 for both polar regions.

The Arctic

Here is the sea ice concentration 23 April 2017 compared with the  1989-1993 mean on the 23 April. Red shades = less sea ice than the 1989-93 mean on 23 April, and Blue shades = more sea ice than the 1989-93 mean on 23 April.

The mean Arctic sea ice for the years 1989-93 on 23 April, the sea ice concentration on 23 April 2017 and the difference between the two data sets. Blue shades imply more sea ice and reds imply decreased sea ice compared with the mean. The original data come from the DMSP SMMI data set at the NSIDC.
The mean Arctic sea ice for the years 1989-93 on 23 April, the sea ice concentration on 23 April 2017 and the difference between the two data sets. Blue shades imply more sea ice and reds imply decreased sea ice compared with the mean. The original data come from the DMSP SMMI data set at the NSIDC.

The stand out regions for me are once more (as in my post in January), the Northern Barents Sea is relatively low, along with the Bering Sea and the Sea of Okhotsk. There is a consistent retreat of the ice edge almost everywhere, and comparatively a lot of open water in Hudson Bay.

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