Daily Global Sea Ice Area and Trend

Per NASA GSFC, a satellite-based data record starting in late 1978 shows that rapid changes have been occurring in the Arctic, where the ice coverage has been declining at a substantial rate, particularly in summer. In contrast, in the Antarctic the sea ice coverage has been increasing although at a lesser rate than the decreases in the Arctic. Shown below are up-to-date satellite observations of the sea ice covers of both the Arctic and the Antarctic, along with comparisons with the historical satellite record of more than 40 years.

Context: Not subject to urban heat island effects, the trend in global sea ice extent is a primary indicator of climate change, or the lack thereof. The strong difference between the winter and summer anomalies indicates something is going on beyond just a warming. We recently published a peer reviewed paper on the cause of this - the importance of soot on ice and light-colored surfaces in climate modeling.

This page, alone, provides proof of the validity of this paper. This is among the observations that led to the paper. In the winter months, the ice extent and the ice coverage both come close to the earliest available records from the 1970s and 80s. This is true for both the Arctic and Antarctic. However, once the sun comes up over the Arctic in the spring, the black carbon/soot that lies on the ice and in the atmosphere over the ice leads to rapid melting and commensurate loss of ice. This does not happen in the Antarctic, where there is much less soot, both on the ice and in the air. These changes can be seen in the below NASA graphics.

If there is still doubt about the validity of this observation, please watch the Smithsonian Channel program on mighty cruise ships, where the ship Roald Amundsen goes through various parts of Antarctica. All the snow and ice is pristine white in the height of summer. An alternative is this video https://www.youtube.com/watch?v=3c-2TBXw6ls In contrast, the Arctic snow and ice is virtually black. As each layer of soot from prior years is reached during melting, it adds to the darkness, until finally the ground is reached. Whether on land-ice or on sea-ice, striations of black lines are dominant features. There is no unblemished whiteness in the summer Arctic, whereas there is no or little visible soot on summer Antarctic ice. Then, look at any YouTube photos or video of the Arctic. The ice is filthy. This is probably why the tour agency brochures don’t show the ice. You might not want to go! Here is an example from a tourist: https://www.youtube.com/watch?v=iFfcwfiLfn0 and from a BBC report: https://www.youtube.com/watch?v=vxu9C81ceVw . For those scientists who think that Arctic warming is due to melting ice that exposes more open water that is darker and soaks up more solar energy, and/or the soot in the Arctic air makes the air warmer, or the biota living in the ice makes it darker, I challenge you to view these videos and photos, then think again. It is clearly the dirty ice causing most or all of the warming and melting - not the CO2, nor the clear water, nor biota, nor the airborne soot.

The huge loss of summer ice makes it difficult for winter ice to rebuild. The water and land have residual heat providing too much inertia for rapid snow accumulation and ice formation on the sea. Even so, the Antarctic sea ice extent and area are within 5% of the earliest available data, throughout the year. The Arctic is about 12% less in winter than the earliest available data and 25% in summer. Of note is that this is some 25% more than in 2012 and 10% more than 2007.

Opportunities to collaborate on our programs or through tax-deductible donations are available at the Everett-Vehrs Conservation and Research Foundation.

For a full suite of graphics and videos showing sea ice at both poles go to the NASA Sea Ice site.

(Source: Cryospheric research at NASA's Goddard Space Flight Center).

Arctic Sea Ice Area and Trend

Arctic Sea Ice Area and Trend

Analysis: Global sea ice is a primary indicator of warming or cooling, but data only go back to 1979, when satellite sensors and analytical programs could get a handle on measuring the area covered by sea ice. Even today it has problems, such as dealing with water on ice, as happens after a warm spell. The sensor sees water, not ice, but this does not mean the underlying ice is gone. If the Arctic loses ice, but the global balance is about the same, there is a lower liklihood of global warming. Per the NOAA National Snow and Ice Data Center a couple years ago, "While Arctic sea ice has set record lows, Antarctic sea ice has set record highs." Something has gone awry when all we hear from the news media and the pro-warming community is that Antarctic is doing as poorly as the Arctic. This dichotomy is not explained by the CO2-based models. Both should be the same. Attempts to explain through evaluations of atmospheric flows or ocean currents do not appear credible. The modelers need to get up from their desks and walk around on the ice they are modelling. The truth depends on it.

In 1988, upon making the switch from natural cycle and pollution-based global cooling to CO2-based global warming, this author told his team working on Ocean and Coastal Zones during their first meeting in Moscow, that evidence of warming would be convincing when it included an acceleration in the steady rise of sea level (from the prior ice-age) and a drop in the amount of global sea-ice. Neither has happened. We still don't have an integrated assessment to analyze the global sea ice data. Nevertheless, here are the two poles that can be visually integrated to show that global sea ice is being strongly decreased by the Arctic and slightly increased by the Antarctic, whose trend line remains increasing at 0.7%/year. The Antarctic is much greater, so the loss overall is relatively small.

 




This page updated or reviewed in September 2022