Distant events often affect our Chihuahuan Desert region. More and more, we're coming to understand that sea surface temperatures off the coast of South America affect our precipitation through the phenomena known as El Niño and La Niña. At least a few past events were even more widespread in their results.
Two catastrophes, or possibly combinations of disasters, caused
worldwide damage to life. Some 65 million years ago, a body from space struck what now
is the northern edge of the Yucatan Peninsula. Possibly with the aid of vast outflows
of lava elsewhere, this event apparently terminated numerous forms of life—famously, of
course, the dinosaurs. Now, some scientists believe they have pinpointed a similar
cause for the mother of all extinctions: at the end of the Permian, some 251 million
years ago. At that time, more than 80% of marine species and 70% of terrestrial types
disappeared. Geologists now wait for confirmation that a structure off the coast of
Australia is indeed a meteoritic crater. The accusation has been made. We await the
verdict: Guilty or not guilty?
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.