In this day of superfast computers, instant news on our phones and round-the-clock coverage on our televisions, it's humbling to be reminded just how crude is our understanding of weather.
Yes, meteorologists have made tremendous strides in the past 60 years, but the science of weather forecasting still is relatively young.
It's remarkable to consider that one of the ways in which scientists have been gathering information to forecast Sandy's path and intensity has been to launch extra weather balloons each day from the more than 120 National Weather Service offices around the country.
Weather balloons collect information on wind speed and direction, temperature, air pressure and humidity levels. Balloons normally are launched daily at 6 a.m. and 6 p.m. Since Friday, however, two additional balloons have been launched each day — at noon and midnight. Scientists launched the last, extra balloon at noon Monday.
Information gathered by the sensors on these balloons is beamed to a supercomputer in the Washington, D.C., area for use in complex weather modeling. Without real-world data, computer modeling essentially builds from educated assumptions, and a small error early on can become magnified. This is why accurate, raw data is the holy grail of forecasting.
The computer also collects raw data from other sources: sensors on airplanes, buoys in the oceans and satellites.
In total, more than 2 billion bits of data are fed into the supercomputer to come up with forecasting information. The computer selects only the best data — about 240 million bits — and runs its calculations at a rate of at least 15.5 trillion a second to project weather conditions. This information is then further vetted and refined by humans.
As impressive as this effort is, it's amazing to ponder the connection between the incredibly costly and high tech calculus of a supercomputer and the simple act of lofting a balloon, with its tiny cargo, skyward.
The balloon ascends to about 100,000 feet before popping. At that point, a small parachute slows the fall of the packet of sensors. The packet includes information for its return, via the mail, to the federal government for refurbishing.
Source: National Oceanic and Atmospheric Administration, National Weather Service/Valley, World-Herald archives
Video: The National Weather Service in Valley launching weather balloons to help in the forecasting for hurricane Sandy.