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Friday, June 1, 2012

Heidi Cullen, NYT: Clouded Forecast

Clouded Forecast

by Dr. Heidi Cullen, The New York Times, May 31, 2012

OUR ability to forecast the weather is in big trouble.
Last month, the National Research Council concluded that the nation’s system of Earth-observing satellites is in a state of “precipitous decline” and warned of a “slowing or even reversal of the steady gains in weather forecast accuracy over many years.”
This worrisome development puts all of us in harm’s way and should particularly trouble us as the annual six-month hurricane season begins today.
Gathering timely and accurate weather data is, of course, vital to saving lives. The deadliest hurricane ever to strike the United States hit Galveston, Texas, on September 8, 1900, killing as many as 8,000 people. Scientists had lacked the tools to predict the storm’s severity.
We have made tremendous progress in the accuracy of our hurricane forecasting (and overall weather forecasting) since then, much of it a result of government-owned satellites that were first launched in the 1960s and now provide about 90% of the data used by the National Weather Service in its forecasting models. Satellite and radar data and the powerful computers that crunch this information are the foundation of the weather information and images we get. Thanks to these instruments, for instance, the 5-day hurricane track forecast we get today is more accurate than the 3-day forecast from just 10 years ago.
These satellites also monitor volcanic eruptions, rising sea levels, melting ice sheets, the depletion of stratospheric ozone and ocean surface temperatures. Emergency beacons from aviators and mariners in distress can also be pinpointed by these satellites. Scientists who study the atmosphere and the ocean need continuous weather data to track large-scale climate variations (like El Niño) and long-term environmental trends like global warming.
Weather observations even bear on national security. Accurate wind and temperature forecasts are critical in deciding whether to launch an aircraft that will require midflight refueling.
But those capabilities, and our overall ability to monitor the planet, are slipping. The causes identified by the research council, an arm of the National Academy of Sciences, are many: technological failures, cost increases, changes in Congressional and administration priorities and — above all — the failure to devote adequate resources. For example, the annual budget for NASA’s Earth Science Division has fallen to below $1.5 billion from about $2 billion a decade ago, far below what scientists agree is needed.
The new report found that the number of actual and planned satellite missions could decline from 23 this year to only 6 in 2020, reducing the number of Earth-observing instruments in space from 90 now to about 20 in 2020.
To make matters worse, in the last three years, two Earth-observing satellites costing more than $700 million failed to reach orbit and crashed into the ocean.
In its May report, the council warned of a “coming crisis” in which “our ability to observe and understand the Earth system will decline.” The National Oceanic and Atmospheric Administration, which includes the National Weather Service, expects a data gap of at least 12 months, beginning in 2017, between the time one satellite crucial for accurate weather forecasts and warnings stops functioning and its replacement is up and running. Without such data, the Weather Service would have been at a serious disadvantage sizing up the dangerous snowmaggedon blizzard of 2010 that paralyzed the East Coast. Forecasters would have underestimated the snowfall by 10 inches, according to the Weather Service.
We live on a small planet with increasingly big problems. Extreme weather, climate change, population pressure and the depletion of our natural resources are all expected to worsen in our lifetimes. This is not the time to take our eyes off the planet we call home.
[ENVISAT stopped working this year, meaning I have no eye in the sky on the Greenland ice sheet changes, anymore.]
Heidi Cullen is a scientist at Climate Central, which communicates scientific findings to the public.

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