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? It’s 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.
There’s 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
the
The
The
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
The
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.
It’s 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 “island” 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 (that’s
more than 21 degrees Fahrenheit!) warmer than the surrounding area.
Precipitation
measurements are even more difficult. Because of the geographic variability of
Richmond — the dense city, sprawling suburbs, and rolling farmland — all
located in a relatively small area, it’s 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 wasn’t
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 observer’s
standpoint, its frustrating for me to watch and know
that the official data reported to the National
Climactic Data Center isn’t completely
representative of the area.
Now that we’re 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 Service’s Cooperative
Observer Program. (http://www.nws.noaa.gov/om/coop/become.htm) It’s 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
what’s actually happening on the ground. I’ve been a spotter since 2007, and
it’s been a great resource. You can find more about the SKYWARN program through
the National Weather Service’s Wakefield office website.
History and need have
dictated why our official observations are taken at the airport, but it’s 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 region’s climate.
(Header image credit:
NOAA; original can be found here)
(http://www.photolib.noaa.gov/htmls/wea01351.htm)