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Announcing Citizen Science Challenge 3: Capturing storm images using cameras, weather radars and satellites

1615 CST. The circle on this GOES weather satellite image indicates a large thunderstorm cell that formed over South Texas on the afternoon of 16 June 2004. Click image to enlarge.

Some Citizen Science Challenges can be accomplished in an afternoon. This is an example of such a challenge.

While individual clouds and contrails are often difficult to find on satellite images, large thunderstorms and squall lines can be easy to spot. This challenge proposes capturing images of specific cloud formations or storms from the ground using cameras and weather radars and from space using satellite images.

The GOES image above shows a large thunderstorm cell that formed over South Texas on 16 June 2004. The most remarkable feature of this storm is that its top punched through the troposphere to an altitude of about 18 kilometers (60,000 feet).

A high quality camera is not necessary for basic cloud photography. The photographs shown below were made with a Nikon Coolpix 4300, a digital camera with a resolution of 4 million pixels. Much less resolution would be fine, as demonstrated by the fact the images shown here are only 250 pixels wide. An inexpensive disposable film camera will also work well.

1514 CST. The outer edge of the storm's anvil-shaped top reached the author's site in South Central Texas when the center of the storm was 145 kilometers (90 miles) away. Click image to enlarge.

1808 CST. The edge of the anvil remained in place as the storm slowly moved south-southwest. Note the contrail behind the passenger jet flying under the edge of the anvil. Click image to enlarge.

1826 CST. The well-defined edge of the anvil top of the storm. Note the streamers moving toward the edge of the anvil. Click image to enlarge.

1834 CST. This photograph was taken while the Sun was slipping below the horizon. Within minutes the entire anvil dissipated. Click image to enlarge.

The large storm in the photographs above was clearly visible in imagery from two of NOAA's GOES weather satellites and in images from NASA's Aqua remote sensing satellite. The images below are from GOES-12.

The core of the storm is located just above the lower arrow in the image at above left. This central core moved slowly to the south-southwest while the anvil remained in place.

The National Weather Service has a Doppler weather radar 19 kilometers (12 miles) from my site. This distance is only slightly greater than the 18 km height of the storm that is the subject of this article.

In this radar image, the center of the storm is about 145 kilometers (90 miles) from my location ("+" sign).

The linear, diagonal cloud feature between San Antonio and Austin was described as a sea breeze front by a television meteorologist who also provided the height of the storm cloud. However, the GOES image at above left suggests that the feature is an outflow boundary from the storm.

The images here show an entire thunderstorm cell from space and as scanned by a powerful radar. They also show how the edge of the storm's anvil top appeared to my camera.

The challenge is for you to document major cloud formations in a similar fashion. Students might find this Citizen Science Challenge to be a viable topic for a science fair project.

Consider reporting your results in a notebook or, even better, a web site. Develop a common format for displaying photos and satellite and radar imagery. Consider including barometric pressure, dew point and temperature at regular intervals during passage of the weather system or cloud formation. All these parameters can be significantly altered by passage of a major cloud system. After you have documented a number of cloud formations, try to draw conclusions about your findings.

Use great caution, of course, when studying thunderstorms that produce nearby lightning. Be aware that lightning can occur 8 or more kilometers (5 or more miles) from the main part of a storm.

Be sure to acknowledge the source of your images. In this case, for example, I acknowledge the National Weather Service for providing the GOES-12 images and the radar image.