Weather Related Handy Facts
- Thunder and the distance to the Lightning
- Sound travels about five miles per second, so start counting "1 steamboat
- 2 steamboat - ..." [each steamboat is about a second] and then divide by
5 to get to the number of miles you are from the lightning. If you want decimal
miles, multiply by 2 and divide by 10 (eg, if you get to 7 steamboats, 7 x
2 is 14 , so the lightning strike is 1.4 miles from where you are.
- How much equivalent rainfall is there in snow?
- According to the National Snow and Ice Data Center (www.nsidc.org):
The commonly used ten-to-one ratio of snowfall to water content is a myth
for much of the United States. This ration varies from as low as 100-to-one
to as high as about three-to-one depending on the meteorological conditions
associated with the snowfall.
- When it is snowing, what is the average accumulation?
- Nationwide in North America, the average snowfall amount per day when
snow falls is about two inches, but in some mountain areas of the West,
an average of seven inches per snow day is observed. (www.nsidc.org)
- How much will the oceans rise if the glaciers melt?
- According to the United States Geological Service (www.usgs.gov),
if the glaciers on Greenland melt completely, the oceans will rise about
6.5 meters (over 21 feet). If the ice cap on Antartica melts completely,
the oceans will rise an additional 64.8 meters (over 212 feet). If all the
glaciers in the world melt, the total rise in the oceans worldwide will be
80.32 meters (over 263 feet - that is one quarter of the height of the Chrysler
If the oceans rise by only 10m (about 33 feet), at least one quarter of the
population of the USA will have to find somewhere else to live.
- Will the ocean rise happen slowly or quickly?
- Melting of the West Antarctic ice sheet would result in a
sea-level rise of about 8 meters (over 26 feed). The West Antarctic
ice sheet is especially vulnerable, because much of it is
grounded below sea level. Small changes in global sea level
or a rise in ocean temperatures could cause a breakup
of the two buttressing ice shelves (Ronne/Filchner and Ross).
The resulting surge of the West Antarctic ice sheet would
lead to a rapid rise in global sea level.
(From the United States Geological Service
In one area, around the Amundsen Sea in West Antarctica,
glaciers are dumping more than 110 cubic kilometres of
ice into the ocean each year, Eric Rignot of NASA's
Jet Propulsion Laboratory in California, US, told a
meeting at the Royal Society in London, UK. This loss,
which is increasing each year, is many times faster than
the ice can be replaced by snowfall inland, he says.
The impending ice disaster centres on Pine Island Bay
on the shores of the Amundsen Sea, where the Pine Island
and Thwaites glaciers enter the sea. These glaciers,
like many in West Antarctica, are perched on underwater
mountains. The meeting heard that warmer ocean waters
are circulating beneath the ice and melting their bases
at a rate of 50 metres a year.
As this happens, the glaciers float clear of the submarine
mountains and slide into the ocean. According to
Andy Shepherd at the University of Cambridge, UK,
they are discharging ice three times faster than a decade ago.
These glaciers are being dubbed the "plug hole"
of the West Antarctic Ice Sheet.
If the Pine Island and Thwaites glaciers disappeared,
they alone could raise sea levels worldwide by more than a metre, says Rignot.