"Several news source are reporting the likelihood of an impressive show of the Aurora Borealis visible as far south as Washington D.C.
this evening. Accuweather explains: 'On the Kp index, the flare has
been categorized at 6 to 8. This is a scale for measuring the intensity
of a a geomagnetic storm. The 6 to 8 rating means that the effects of
the radiation will have a greater reach. ... The radiation from such a
flare may cause radio wave disturbances to electronics such as cell
phones, GPS and radios, causing services to occasionally cut in and out.
While traveling slower than was originally anticipated, the flare
effects are moving towards Earth at 1000 km per second. ... The lights
are currently estimated for 8 p.m. EDT Saturday arrival, with a possible
deviation of up to seven hours.' Check the map; if you're in a
fair-to-good zone, head out after sunset to see the show."
Scientists from the National Oceanic and Atmospheric Administration have
published research into the shrinking levels of sea ice in the Arctic.
They wanted to figure out how long it would take before summer sea ice
disappeared entirely. Since there's no perfect model for predicting ice
levels, they used three different methods. All three predicted the Arctic would be nearly free of summer sea ice by the middle of the century,
and one indicated it could happen as early as 2020. Two of the methods
were based on observed sea ice trends. If ice loss proceeds as it has in
the past decade, we get the 2020 timeframe. If ice loss events are
large, like the 2007 and 2012 events, but happen at random some years,
the estimate is pushed back to 2030. The third method uses global
climate models to 'predict atmosphere, ocean, land, and sea ice
conditions over time.' This model pushes the timeframe back to 2040 at
the earliest, and around 2060 as the median (abstract).
One of the study's authors, James Overland, said, "Rapid Arctic sea ice
loss is probably the most visible indicator of global climate change;
it leads to shifts in ecosystems and economic access, and potentially
impacts weather throughout the northern hemisphere. Increased physical
understanding of rapid Arctic climate shifts and improved models are
needed that give a more detailed picture and timing of what to expect so
we can better prepare and adapt to such changes. Early loss of Arctic
sea ice gives immediacy to the issue of climate change."
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