Friday, June 20, 2008
Philip Gladstone makes weather statistics dependable
Philip Gladstone of Curve Street, who was recently honored as a National Oceanic and Atmospheric Administration (NOAA) Environmental Hero of 2008, should also be called a
“data quality hero.” Using his weather knowledge and data collection expertise he has made it possible for over 5,000 weather observers from across the country to automatically and accurately report data from their personal weather stations to NOAA via the Citizen Weather Observer Program (CWOP). The data collected from their observations are used by many federal and local agencies, colleges, universities and research firms to improve warnings for hurricanes, storms and floods.
A grandfather’s inspiration
Gladstone, who grew up in England, gained early experience collecting weather data with his
grandfather, Gavin Goodhart, “who lived in Inkpen, a small village near Newbury in the county of Berkshire,” said Gladstone. Goodhart was an extremely exact record keeper, who kept rainfall data for the United Kingdom Meteorological Office for 50 years. While visiting his grandfather, Gladstone explained, “I would go out and collect the little glass measuring tube from the brass rain gauge and read it.” His grandfather would then have him bring the tube to the house “for him to check my reading, and nobody except my grandfather was allowed to write in the official log. He was quite a stickler for rules.” This must have inspired Gladstone’s concern for accurate data.
The English have long been obsessed with weather records, and data can be found in ships’ logs, and farmers’ notes. In America, Thomas Jefferson was almost compulsive in compiling weather data, which he did daily from 1776 to 1816.
The first network of weather stations was set up as a result of an act of Congress in 1890, and
in 1953 the government began to install weather stations every 25 miles across the country, using volunteers to maintain government-installed stations. Gladstone notes many of these stations, located years ago in fields or other open spaces, are now jeopardized by development. He recalled finding a weather station close to the side of a paved road in New Hampshire, which was likely installed long ago when this was a “quiet side road.” To be valuable, weather stations need to have a continuous history, Gladstone pointed out: “You don’t want to move a station. It’s been there for 30 years.” To move it means to start a new history.
Creating CWOP tools
Gladstone’s technical background is extensive. He is currently a Distinguished Engineer at Cisco Systems working on computer security. He is an advocate of “freeware”: open-source software that is available free on the Internet. Gladstone volunteered his time to create the CWOP suite of reporting and quality assurance tools. Weather recorders use the online tools to report their data, including temperature, humidity, air pressure, wind speed, and direction, and rainfall, to NOAA’s Meteorological Assimilation Data Ingest System (MADIS). His quality assurance tools have also made it possible for data providers to correct issues with their weather station readings. “The original idea was a way that a person could sign up and get daily e-mails about the quality of their observations,” he explained. “There are now a few professional people who use this system as well.”
Gladstone’s system imports the data files from MADIS and e-mails the daily station performance results to CWOP members. As an added benefit, weather station owners can uplink improved readings once they make corrections.
The system creates a page at www.wxqa.com, the CWOP site, for each weather station, and displays the analysis of the weather station sensor performance, suggesting solutions when certain problems are identified. For instance, volunteers may receive a report that their heat and humidity readings are abnormally high. A recommendation would be to check the siting of a weather station, which can impact the temperature data. Sensors that are placed above concrete, for example, will receive more heat from the sun. A rain gauge placed below the eaves of the house will not collect rain appropriately, while placing an anemometer (that measures wind) at five feet will measure only ground surface winds (best is above 13 feet). “The types of errors in measuring wind speed are different from measuring temperature,” Gladstone explained. “With temperature there is often an offset error. With wind speed, pretty much everybody gets 0 mph right,” he said.
Gladstone’s own system
When he moved to Carlisle in 2001, Gladstone set up his weather station in his backyard by the Wang-Coombs Land. Each weather station has a unique identifier and, as one of the first to join CWOP, Gladstone is proud of his identifier, “CW0003,” which is one of the first assigned. His weather station, pieces of which are perched on the roof of his house, contains two anemometers, barometer, rain gauge, and dew-point indicator. Gladstone’s system is reporting good daily barometer readings:
“Average barometer error: 0.9 milliBars
Error standard deviation: 0.3 milliBars
These values are within range, so your sensor is probably calibrated correctly.”
Gladstone’s dewpoint readings produced this comment:
“The mean error of your daytime readings is significantly different [compared] to the mean error of your nighttime readings. In particular, the difference is 3.9° F warmer during the night. This is often caused by poor siting of the sensor (e.g., under eaves, in screen porch, or in thick tree coverage).”
Gladstone explained that his data is intermittent, “and that is why the curve looks terrible.” He has his temperature and dew point gauge next to his pond, which affect the readings. His gauge communicates with his computer via a buried wire, “which has taken a couple of lightning strikes, so it doesn’t work too well.”
He also has problems with his rain gauge, which is located on his roof and works “terribly,” he confessed. Asked why he put it up there, he said, “I wasn’t thinking at the time. I had a friend do it, but I am too frightened of heights to take it down.” He noted also that “the birds have deposited poop, which impacts the data.” After that bit of dry, British humor he said he is doing away with the whole thing for a new wireless system.
Gladstone shares his interest in extreme weather with his family, or at least tries to. While the family was vacationing in the Cayman Islands, a waterspout appeared as they were swimming with stingrays. “Though,” he said, “the kids remember kissing the stingrays rather more than the waterspout.”
During the storm in Carlisle on June 10, Gladstone’s station recorded “a very dramatic pressure spike at about midnight to 2 a.m.,” he said. The data from a nearby station noted an almost immediate drop in temperature of 10 degrees. Weather stations are out in all weather and can take a beating. “My temperature sensor died in the last thunderstorm,” he said. “The thunderstorms around here always impressed me, though the most impressive ones I ever saw were in Johannesburg [South Africa] when I was on a business trip. [They occurred] every afternoon!”
Gladstone is a true weather aficionado, and enjoys watching storms with his family. “When the kids were younger, and the thunderstorms would happen in the evening, we would open all the curtains and sit and watch the storm and appreciate it. The idea was make sure that the kids were not frightened of thunderstorms.”
For more on weather stations visit http://home.comcast.net/~dshelms/CWOP_Guide.pdf ∆
© 2008 The Carlisle Mosquito