Nearly every single weather station the U.S. government uses to measure the country's surface temperature may be compromised, say critics. Sensors that are supposed to be in empty clearings are instead exposed to crackling electronics and other sources of heat, from exhaust pipes and trash-burning barrels to chimneys and human graves.
Here are nine of the worst offenders, thanks to SurfaceStations.org.
This temperature sensor (MMTS, for maximum minimum temperature sensor) sits far too close to a parking lot, where air conditioners exhaust hot air, firefighters often barbecue and a cell phone tower base emits warmth.
This temperature sensor sits awfully close to a house, with an air conditioning unit nearby, automobile parking, and the chimney for a fireplace. Note also the barbecue grill -- directly beneath the sensor.
This weather station sits over a tombstone. While the effect of of a grave on the ambient air temperature may be negligible, it's certainly inappropriate.
At this site in Oregon, the hot exhaust air from an air conditioner blows directly on a temperature shelter. Asphalt and buildings nearby radiate ambient heat as well.
In Aberdeen, a sewage treatment plant near this temperature sensor probably creates ambient warm air. This photo was taken from a parking area just in front of the sensor; the hot automobile radiators of the cars probably influences temperatures as well.
A barrel for burning trash and its aluminum exhaust tube sit a mere 5 feet from a temperature monitoring station in California. And just as asphalt parking lots radiate heat in the summer, a nearby tennis court has a similar effect.
Warm air rises, right? Well, the warm air from this house in Oregon rises through the roof -- directly up to a roof-mounted temperature sensor. Where an air conditioner exhausts its hot air.
A light bulb in a temperature sensor's shelter may make it easier to take a reading. And the heat from the bulb may also affect the temperature inside the shelter.
Yes, that's an airplane in the background: This temperature sensor sits beside the Petaluma airport in California. It's also six feet from a house, where air conditioners exhaust directly towards it.
Car and plane exhaust warms the air, right? So why are the National Climate Data Center's thermometers so close to them? Here, sensors in 9 of the oddest locations.