today
9 a.m. T-ball Registration Boys and Girls Club Teen Center
read >9 a.m. Apple Solutions for Small Business See Event Description
read >9 a.m. Doris Niles Humboldt County Science Fair Humboldt State University
read >10 a.m. Annual Juggling Festival Humboldt State University
read >6 p.m. Americans for Safe Access Bayview Courtyard Complex
read >6 p.m. Apple Solutions for Small Business Fortuna River Lodge
read >7 p.m. Blondies Open Mic Night Blondies Food And Drink
read >7:30 p.m. A Midsummer Night's Dream Arcata High School
read >8 p.m. Karaoke at Bear River Casino Bear River Casino
read >8 p.m. Karaoke Blue Lake Casino
read >8 p.m. On the Wings of a Dove Carlo Theater (Dell'Arte)
read >8 p.m. Moscow State Radio Symphony Van Duzer Theatre
read >8 p.m. Random Acts of Comedy Arcata Theater Lounge
read >8 p.m. Antigone College of the Redwoods
read >9 p.m. Lisa Baney Cher-Ae-Heights Casino
read >9 p.m. Wig-in-a-Box Karaoke at Aunty Mo's Aunty Mo's Lounge
read >9 p.m. Aftershock Thursdays w/ Da Foot Clan Nocturnum
read >9 p.m. Children of the Sun (blues) Six Rivers Brewery
read >9 p.m. Skerdio, Psy Fi Red Fox Tavern
read >9:30 p.m. Woven Roots, Monk (reggae) Humboldt Brews
read >10 p.m. DJ/Thirsty Thursday Central Station Cocktail Lounge
read >previous columns
Jan. 31, 2008
Stick-Slip Slug Slime
Banana slugs evolved from snails, and both are classified as ...
read >Jan. 24, 2008
Watts in Coffee, Pot and Brakes?
I am reading a full page ad in our local ...
read >Jan. 17, 2008
What is Our Bedrock?
Our bedrock consists of an exceptional diversity of rocks spanning ...
read >Photos
Can You Predict Rain?
By Don Garlick
Yes, by simply learning how to interpret available data. The best window into tomorrow's weather is a movie which compresses several hours of satellite-observations into a few seconds: Google "Eureka Weather" and click Current Conditions — East Pacific — Infrared — Loop. After some experience you will be able to reasonably forecast our weather by extrapolating those satellite observations. For precipitation within the next few hours, click Doppler Radar. The following is an introduction to the science behind these sophisticated tools.
The diagram plots the atmospheric absorption of radiation ranging from ultraviolet (wavelength < 0.4 microns) through visible light (0.4-0.7 microns) and reflected infrared (0.7-3 microns) to thermal infrared (wavelength > 3 microns). The UV absorption is due to ozone. Most of the rest is due to water vapor, excepting those bands shown darker which are due to carbon dioxide. Absorption near 13 microns is of global warming concern.
A geostationary satellite 35,786 km above the equator detects radiation at a variety of wavelengths. One detector near 0.7 microns provides the positive "VIS" image composed of reflected visible sunlight. One near 11 microns yields the negative "IR" image. It is centered on an atmospheric window which transmits thermal infrared energy from the Earth's surface, providing clouds are absent. When clouds are present, their cool tops radiate less energy (lighter tones in the negative image). When storm clouds reach very cold altitudes, the IR image is enhanced with false colors. A detector near 7 microns cannot see the Earth's surface because of intervening water vapor. However, when the atmosphere is drier it detects thermal radiation from lower warmer air. This detector yields the water vapor "WV" image (also negative). The IR and WV images are produced day and night. But don't let them keep you awake.
Rain-detecting Doppler radar is next-week's topic.


















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