A scientist prepares to launch a radiosonde. Click on image for full size (500K) Courtesy of the Digital Image Library, UCAR

Radiosondes: Scientists have been using these helium-filled weather balloons since the 1930s. As the balloon rises into the atmosphere, an instrument package attached to it measures temperature, pressure, and humidity at frequent intervals. The readings are sent via radio to a ground station. By monitoring the location of the radiosonde with Global Positioning System (GPS) technology, researchers can also infer wind speed and direction. During MILAGRO, teams based at ground sites in the Mexico City vicinity will launch radiosondes to make vertical profiles of the atmosphere.

Tethersonde: A tethersonde is very similar to a radiosonde, except that the instruments are attached to a tethered (fixed) balloon. The tether keeps the instrument package closer to the ground, limiting its readings to the boundary layer, or layer of the atmosphere that is just above Earth's surface where wind is influenced by friction with topography. The instruments can move up and down the tether for a vertical profile.

Wind profilers: Wind profilers are sensors that continuously measure wind speed and direction up to about 13,000 feet (4,000 meters) by detecting signals from microwave radar beams that are directed upward. MILAGRO researchers will deploy wind profilers near Mexico City to measure wind speed and direction. This will help them determine the paths of air pollution particles that blow out of Mexico City.

Mobile laboratories: The MILAGRO researchers will use a variety of laboratories based in vans and trailers. The labs, which contain instruments for sampling particles and gases in the air, will be deployed throughout the Mexico City basin.

Satellites: MILAGRO researchers will also use data retrieved by satellites circling Earth to learn more about the distribution of clouds, aerosols, and different chemicals in the atmosphere. One satellite they will look to is MOPITT, which flies on NASA's EOS Terra spacecraft. The satellite measures the distribution of the pollutant carbon monoxide in the troposphere, or lowest layer of Earth's atmosphere.

Radiosonde Video: (60 Mb)
Radiosonde Video, smaller version: (7 Mb)

A scientist prepares to launch a radiosonde. Click on image for full size (500K) Courtesy of the Digital Image Library, UCAR

Radiosondes: During MILAGRO, teams based at ground sites in the Mexico City area are launching radiosondes. Scientists have been using these weather balloons since the 1930s. As the balloon rises into the sky, instruments attached to it measure temperature, pressure, and humidity. The measurements are sent by radio to scientists on the ground. By keeping track of the location of the balloon in the sky, researchers can also determine wind speed and direction.

Tethersonde: A tethersonde is like a radiosonde but is tethered (fixed) to the ground with a cord. The cord keeps the balloon and its instruments closer to the ground, limiting measurements to the lowest layer of the atmosphere that is just above Earth's surface. Researchers can move the instruments up and down the cord.

Wind profilers: Wind profilers are instruments that measure wind speed and direction up to about 13,000 feet (4,000 meters). MILAGRO researchers are setting up wind profilers near Mexico City to determine where air pollution particles go when the wind blows them out of the city.

Mobile laboratories: The MILAGRO researchers are using a variety of laboratories based in vans and trailers. The labs, which contain instruments for sampling particles and gases in the air, will be driven around the Mexico City area.

Satellites: MILAGRO researchers are also using data retrieved by satellites circling Earth to learn more about the distribution of clouds, particles, and different chemicals in the atmosphere. One satellite they will get information from is MOPITT, which flies on NASA's EOS Terra spacecraft. The satellite measures the distribution of the air pollutant carbon monoxide in the lowest layer of Earth's atmosphere.

Radiosonde Video: (60 Mb)
Radiosonde Video, smaller version: (7 Mb)

A scientist prepares to launch a radiosonde. Click on image for full size (500K) Courtesy of the Digital Image Library, UCAR

Radiosondes: These balloons are similar to the ones that you see at birthday parties but much larger. They rise into the sky with scientific instruments attached to their cords. The instruments measure things like how hot or cold the air is. Also, the scientists can figure out where the wind is blowing and how hard by watching where the balloons go in the sky. During MILAGRO, scientists will launch these balloons near Mexico City.

Tethersonde: A tethersonde is the same idea as the radiosonde, except that the balloon that is attached to the ground with a cord. The cord keeps the balloon from rising high into the sky. It's best for when scientists just want to measure the air near Earth.

Wind profilers: Wind profilers are shaped like big boxes. They measure how fast the wind is blowing and in what direction. The scientists are setting wind profilers up near Mexico City to figure out where the wind blows the air pollution.

Mobile laboratories: These are science labs on wheels! The scientists keep their equipment in vans and trailers that they can drive anywhere to make measurements and do experiments. During the project, they'll be driving the labs around the Mexico City area to test the air for pollution.

Satellites: MILAGRO researchers will also use data retrieved by satellites. Satellites circle Earth from space. They show scientists where air pollution and chemicals are above Earth. One satellite the scientists in Mexico City are using is called MOPITT. MOPITT can take pictures of air pollution in the sky.

Other instruments on airplanes will also be used during the campaign.

Radiosonde Video: (60 Mb)
Radiosonde Video, smaller version: (7 Mb)