Science Sunday

    Science Sunday is a weekly wrap-up of science news of special interest to Coloradans. Emphasis given to work performed by Colorado researchers, or whose results are of importance (or sometimes just entertaining) to the state.

    How Now Brown Snow

    Snow cover in the San Juan Mountains was shortened by between 18 and 35 days because of dust blowing in from the Colorado Plateau, according to research published by Thomas Painter of Boulder’s National Snow and Ice Data Center and colleagues.

    When dust from the plateau blows into the mountains, it settles darkly on the white snow. This results in the dust and snow combined absorbing more solar energy — a process the scientists call “insolation” — and increases the speed at which the snow melts.Moreover, with global climate warming well under way, additional drought and dust seems likely in the region, meaning that the snow duration in the are could be reduced even further.

    Painter interrupted his vacation in the Alps to talk with us by cell phone. He said:

    “The dust comes in the spring. That’s important because that’s when the sun is getting higher in the sky and there is greater insolation. Dust on the surface in April has a big impact. The sunlight can penetrate snow 30 to 40 centimeters in the visible wavelength. It’s absorbed by the dust particles, which warm and melt the snow layer above them. Generally, the dust layer stays intact.

    “The snow pack gets dirtier and dirtier, coupled with the sun getting higher in the sky,” Painter says.

    The end result may be a changing timetable of water in rivers throughout the region that rely on spring snowmelt.

    The research was published in the June 2007 issue of the journal Geophysical Research Letter. Other Colorado authors who are credited on the paper are Christopher Landry of Silverton’s Center for Snow and Avalanche Studies; and Jason Neff, Corey Lawrence and G. Lang Farmer of CU’s Department of Geological Sciences.

    We’re All Vampires!

    It isn’t Colorado research exactly, but the July/August issue of The Skeptical Inquirer demonstrates that if there’s one vampire loose that follows the infectious rules of Hollywood vampiredom, then everybody on earth would be a vampire after less than three years.

    In the movies, a vampire bites a human victim and turns him or her into a vampire. Then there’s two vampires. Well, a vampire’s gotta eat, so those two go out and bite two more humans. Now you’ve got four hungry vampires, each of whom has to eat.

    If you started this process in year 1600 A.D. — I suppose the authors chose this date because it is sufficiently distant and gothic — when the population of the world was about 537 million people, and if the vampires ate only once a month (which you’ve got to admit  is pretty restrained for a Hollywood vampire) then everybody in the world would be a vampire after 29 months.

    The calculation is a variation of the fable about the serf who asks the king to double the grains of rice on each square of a chess board as his reward for some good deed, beginning with one grain on the first square. He ends up with two to the 64th power (minus one) grains of rice, which is a heck of a lot of rice, eighteen quintillion grains, give or take.

    The vampire math was presented by University of Central Florida physicist Costas Efthimiou and UCF student Sohang Gandhi.

    The Perfect Storm Damage Assessment

    The last ten years have seen increased hurricane activity and more than $150 billion in damage in 2004 and 2005. This may or may not be the result of global climate change. We don’t want to go there. Experts disagree, as they sometimes will.

    But now the University of Colorado Center for Science and Technology Policy Research Director Roger Pielke says that if you “normalize” the damages, the decade 1995 to 2005 saw the second-most damage of any decade since 1900.

    Normalizing provides an “estimate of the damage that would occur if storms from the past made landfall under another year’s societal conditions. A lot of the reason that coastal damage estimates have gone up in recent years is because there is more development on the coasts than there used to be. the decade with the most “normalized” damage was 1926-1935, which at the time they probably blamed on the Hoover administration.

    “Unless action is taken to address the growing concentration of people and properties in coastal areas where hurricanes strike, damage will increase, and by a great deal, as more and wealthier people increasingly inhabit these coastal locations,” Pielke and colleagues wrote in a paper accepted for publication (.pdf) by the journal Natural Hazards Review.

    Mammal Genes Like Day and Night

    Research up until now has indicated that only about 15 percent of mammal genes express themselves in circadian rhythms — that is the 24 hour periods of night and day. But new work from Colorado State University has discovered almost all mammal genes follow circadian oscillations.

    Colorado State University researcher Andrey Ptitsyn, who works in the Bioinformatics Center at the College of Veterinary Medicine and Biomedical Sciences, discovered that “gene activity oscillates in a `finely orchestrated’ system and gene expression can be impacted by daylight and darkness — or a lack of both.”

    This may explain why dieters shouldn’t eat right before bed.

    Ptitsyn’s work appeared in the online, open access journal PLoS Computational Biology

    Shut Up and Swim

    Denver would be 727 feet below sea level if it wasn’t buoyed up by the heat in the earth’s crust, according to a University of Utah study.

    “We found a good explanation for the elevation of continents,” says geologist Derrick Hasterok. “We now know why some areas are higher or lower than others. It’s not just what the rocks are made of; it’s also how hot they are.”

    If it wasn’t for the heat keeping them afloat: