RIVERSIDE, Calif. – A new study shows that the desert tortoise, thought to be one species for the past 150 years, now includes two separate and distinct species, based on DNA evidence and biological and geographical distinctions.
This genetic evidence confirms previous suspicions, based on life history analysis, that tortoises west and east of the Colorado River are two separate species. (more…)
AUSTIN, Texas — An international team of geoscientists has discovered an unusual geological formation that helps explain how an undersea earthquake off the coast of Sumatra in December 2004 spawned the deadliest tsunami in recorded history.(more…)
Rate is greater now than at any time during past 2,100 years
The rate of sea level rise along the U.S. Atlantic coast is greater now than at any time in the past 2,000 years–and has shown a consistent link between changes in global mean surface temperature and sea level.(more…)
Fluctuations in climate can drastically affect the habitability of marine ecosystems, according to a new study by UCLA scientists that examined the expansion and contraction of low-oxygen zones in the ocean.
The UCLA research team, led by assistant professor of atmospheric and oceanic sciences Curtis Deutsch, used a specialized computer simulation to demonstrate for the first time that the size of low-oxygen zones created by respiring bacteria is extremely sensitive to changes in depth caused by oscillations in climate. These oxygen-depleted regions, which expand or contract depending on their depth, pose a distinct threat to marine life. (more…)
AUSTIN, Texas — Atlantic croaker living in the large Gulf of Mexico “Dead Zone” exhibit severe reproductive impairment with potential long-term impacts on the fish’s population abundance, researchers from The University of Texas at Austin’s Marine Science Institute have found.
Males and females were found to produce dramatically fewer sperm and eggs. In addition, females in the hypoxic Dead Zone waters were masculinized — some 20 percent actually produced sperm in their ovaries. The sex ratio was also heavily skewed toward males in the hypoxic area. (more…)
Even underground nuclear tests leave their mark on the part of the upper atmosphere known as the ionosphere, the researchers discovered, when they examined GPS data recorded the same day as a North Korean nuclear test in 2009. Within minutes on that day, GPS stations in nearby countries registered a change in ionospheric electron density, as a bubble of disturbed particles spread out from the test site and across the planet. (more…)
*Widespread urban development alters weather patterns*
New research focusing on the Houston area suggests that widespread urban development alters weather patterns in a way that can make it easier for pollutants to accumulate during warm summer weather instead of being blown out to sea.
The international study, led by the National Center for Atmospheric Research (NCAR), could have implications for the air quality of fast-growing coastal cities in the United States and other mid-latitude regions overseas. (more…)