Thanks to ex-Chicagoan Gary Wojton, now living in the Phoenix area for passing along this photo of a halo around the sun as the sun’s rays were reflected and refracted by the ice crystals in the cirrus clouds.
William Anders snapped a picture of earth during the Apollo 8 mission in 1968 that went on to become one of the most iconic images ever made. Life Magazine included it in their list of 100 Photographs That Changed the World. The picture is referred to as “earthrise” and it shows the nearly half illuminated planet appearing to rise above the lunar landscape.
Now NASA has released some stunning images of earth from the satellite Terra which is orbiting our planet around 435 miles above earth’s surface. The image is composed of a mosaic of satellite data with such fine resolution that it reveals details as small as a third of a mile across. These images are the most detailed to date of earth. The amazing pictures come at a price though. It is estimated the Terra satellite cost about 1.3 billion dollars. It is hoped the information gathered by this school bus-sized satellite will give scientists a better understanding of long-term climate change.
A warming trend is under way, but the chilly air that has dominated the Chicago area for several days is only reluctantly yielding to higher temperatures. Each day’s afternoon temperatures will climb a few degrees higher until readings reach the upper 40s this weekend. Sunshine returns Thursday and Friday, but more clouds arrive Saturday in advance of the next weather system that promises rain by Sunday.
Chilean quake shortens day
According to Richard Gross at the Jet Propulsion Laboratory, Saturday’s earthquake has speeded the Earth’s axial rotation and shortened the days by 1.26 millionths of a second. Some of the planet’s mass shifted slightly closer to the planet’s axis and its rotation quickened, just as ice skaters spin more rapidly 8when they pull in their arms.
What is the largest temperature forecast error that you are aware of?
Rick Burdsall, Palatine
Records of temperature forecast errors are not maintained. However, a forecaster who once served at Cheyenne, Wyo., recalls that the station maintained a checklist for weather factors leading to the onset of chinook winds (warming winds that can suddenly howl down the slopes of the Rockies). Frigid arctic air covered Cheyenne one bitter day in January and the afternoon temperature was 15 degrees below zero. Satisfied that a chinook would not occur and that arctic air would remain in place, the afternoon forecaster called for an overnight low of 25 below. An unexpected chinook developed that night and Cheyenne’s temperature surged to 25 degrees above zero by morning for a 50-degree error within 12 hours of the forecast being issued.