- Every morning at 8 a.m., Louise Hallberg walks through
her butterfly garden to a weather station on the family farm just north
of San Francisco. She checks the thermometer and the rain gauge, and carefully
records the information.
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- The 81-year-old volunteer weather observer later calls
it in to a National Weather Service office, as she has for 30 years. Well,
30 years minus the two days that she missed.
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- Her daily routine, and those of many like her, contributes
to an enormous network of volunteer and professional thermometer-watchers
around the world. They track temperatures that help researchers figure
out whether the Earth is indeed heating up for the long haul and what exactly
that means.
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- Mind-numbing numbers
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- Weather enthusiasts, forecasters and climate researchers
track temperatures at airports, city parks, universities, corporations,
military bases, mountain tops, desert basins, farms, and in the back yards
of private citizens. Instruments on weather balloons, commercial jets,
and satellites measure the temperature of the upper air, while ocean buoys
and ships monitor the sea surface temperature. Torpedo-like devices dropped
from ocean liners measure the cold and murky depths, and pulsing sound
waves gauge changing temperatures across the world's ocean basins.
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- The mind-numbing mountain of data collected so far allowed
climatologists to declare with confidence that 1998 was indeed a record-breaking
year for the planet, the warmest in 1,200 years. From January to November,
the Earth's average temperature was 58.4 degrees Fahrenheit, 1.2 degrees
warmer than the average mean temperature from 1880-1997. What exactly this
means and whether humans are the cause of this latest round of global warming
in the planet's stormy climatic history is heavily debated.
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- Each day computers at the National Climate Data Center
in North Carolina gobble up and feed new information into the world's largest
archive of climate records. In addition to day-to-day information, the
center also tracks down, verifies and archives as many historical records
from farmers, sailors, scientists, and colonial settlers as it can find.
In its own way, the Earth itself has been keeping historical climate records,
and researchers mine them by chiseling information and trends from studies
of glacier ice cores, ocean and lake sediments, tree rings, sea ice and
sea levels.
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- "Gigabits of data come in daily," says Steve
Delgreco, chief of quality control for data operations at NCDC. "We're
looking at terabits in our archives."
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- Weather pioneers
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- Individual weather enthusiasts alone have taken over
300 million temperature readings since 1714 when Mr. Fahrenheit invented
the mercury thermometer, estimates Tom Peterson, a research meteorologist
for the center.
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- Thomas Jefferson kept meticulous rainfall and temperature
records at his plantation and proposed that the country establish a grid
of weather stations to keep track of the climate. The National Weather
Service's Cooperative Observing Network, an array of 12,000 weather stations
scattered in back yards, city streets, and institutions from Maine to California,
does just that.
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- Louise was recruited as an official weather watcher in
1968. In a way, it was destiny: Louise's father started keeping track
of weather on the Sebastopol farm in 1930, and she kept up the meticulous
records after his death.
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- Unfortunately, there aren't enough Louises to go around
and the National Weather Service is depending more and more on automated
stations to collect weather data. San Francisco's official weather station,
now in a city park, has been automated since 1983. Located in the same
seven-block area since it was established in 1849, the station has sweeping
views of the downtown skyline and bay -- a vista wasted on the thermometer
and rain gauge that sit atop a two-story building in Duboce Park.
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- Keeping watch
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- What automated stations lack in human touch they make
up for in the collection of voluminous data. The instruments are always
on, continuously monitoring temperature and rainfall, and sending reports
by modem or radio signal every minute of every day.
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- And Louise keeps her daily watch on her farm, charting
rhythms of weather there and sending what she sees along to those creating
larger global pictures.
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- "I never thought I'd be doing this for 30 years,"
she says, "but here I am."
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- _____________
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- Mary K. Miller, a freelance writer based in California,
works as a senior science writer for The Exploratorium in San Francisco.
She recently co-authored the book Watching Weather: A Low Pressure Book
About High Pressure Systems and Other Weather Phenomena.
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