August 17, 2010
Andrew submitted this question in the comments of one of my recent weather posts:
Why is RIC the default weather station for the area? Itís in a less densely populated area and seems to receive different amounts of precip and have different temps than the rest of the metro area.
Thereís a bit of history involved in this question.
Prior to the Civil War, over 500 locations were voluntarily reporting weather observations via telegraph to the Smithsonian Institution. Many of these stations were forced to cease operation following the outbreak of war, but President Grant signed into law the act creating the predecessor of the National Weather Service on February 9, 1870.
Under the direction of
In the meantime, the
Weather Bureau also established an office at what was then known as Byrd Field
in July 1928. The office there recorded observations in addition to the
Byrd Field received a WSR-3 Weather Service Radar, and it was commissioned on July 7, 1958. The unit was decommissioned in October 1969 for reasons unknown.
In the early 1990s, the
National Weather Service (renamed from the Weather Bureau in 1969) began a campaign
to modernize, automate, and consolidate their facilities, spending $4.4 billion
to reduce their forecast offices from over 250 down to just 116. At the time,
forecast offices were located in
So where are we now?
The need to provide support for the aviation community led to the establishment of the Weather Bureau office at Richmond International, and though consolidation has closed the office, that same need drove the decision to install automated observing equipment at most of the commercial and general aviation airports around the Commonwealth.
Itís hard to answer with certainty questions about whether or not temperatures at the airport are representative of the temperatures experienced around most of the area. There are unanswered questions about the potential influence of the airport and its infrastructure (buildings, runways and taxiways, jet exhaust) on air temperatures recorded at the site.
A location in the city, however, would suffer from other influences, namely an effect called the Urban Heat Island (UHI). In essence, the UHI describes an ďislandĒ of heat created by the development of a city compared to the surrounding rural areas. According to the American Meteorological Society Glossary of Meteorology, the heat created by a city can increase the annual mean temperature by 1-2 degrees Celsius, and on calm, clear nights, the temperature may be up to 12 degrees Celsius (thatís more than 21 degrees Fahrenheit!) warmer than the surrounding area.
Precipitation measurements are even more difficult. Because of the geographic variability of Richmond ó the dense city, sprawling suburbs, and rolling farmland ó all located in a relatively small area, itís going to be hard to take an observation at just one location and get a representative sample. This question was written not long after the snowfall of this past winter, when it wasnít uncommon to see measurements vary by several inches from east to west or from north to south (or in all four directions at the same time), and in a radial distance from the city. Taking a measurement in either extreme fails to completely represent the snowfall received in the area, and finding a median observation fails to take into account the extremes. From an observerís standpoint, its frustrating for me to watch and know that the official data reported to the National Climactic Data Center isnít completely representative of the area.
Now that weíre into the summer thunderstorm season, that variability increases even more. How many times have you had a thunderstorm drop buckets upon buckets of rain at your house, but your office 5 miles away, or even your neighbor down the road, barely saw a drop? It happens just as much at the airport as it does anywhere else.
The solution, in my opinion, would be to take observations from multiple locations in the region, and average these to determine climatology for the region. Records could be kept for each individual station and used for tracking extrema. Is this a viable solution? Not really. The expenses required to select locations, and install and maintain automated weather observing equipment would be prohibitively expensive. The National Weather Service and its parent organization, the National Oceanic and Atmospheric Administration, have been under the threat of budget cuts for the last several years, and have many projects that would take priority over anything of this magnitude.
However, there are ways that you can participate. One way is through the National Weather Serviceís Cooperative Observer Program. †(http://www.nws.noaa.gov/om/coop/become.htm) Itís fairly intense, however, as it requires the National Weather Service to install meteorological observing equipment on your property. Another way is through the CoCoRAHS program: (http://www.cocorahs.org/)† You install a rain gauge on your property and provide daily rainfall observations to a nationwide network of volunteers through a website. All it requires is a rain gauge (available through the website) and a daily commitment to observe the gauge and report the findings online. Third, you can become a trained SKYWARN spotter. Volunteers receive training from National Weather Service employees on how to observe and report various severe weather phenomenon, including thunderstorms, hail, tornadoes, and winter weather. During severe weather events, SKYWARN spotters provide local reports to the National Weather Service and help paint an incredibly valuable picture of whatís actually happening on the ground. Iíve been a spotter since 2007, and itís been a great resource. You can find more about the SKYWARN program through the National Weather Serviceís Wakefield office website.
History and need have dictated why our official observations are taken at the airport, but itís not the only data we have. Volunteer programs like CoCoRAHS have a higher resolution of data points and provide valuable information to meteorologists and the public. While they may not be part of the official climate record, they give us another great picture of a regionís climate.
(Header image credit: NOAA; original can be found here)