Magazine
July-August 1999
July-August 1999
Volume: 87 Number: 4
Recent ice- and ocean sediment-core studies have revealed that the average global atmospheric temperature has changed as much as 10 degrees Celsius in less than 20 years. In "Rapid Climate Change," Kendrick Taylor reviews the evidence for such changes and raises the question of whether greenhouse-induced warming may precipitate a return to an ice-age climate. Here Rhonda Ecker from the University of Nebraska inspects an ice core that has just been recovered from a depth of 90 meters at Siple Dome, Antarctica. The drill used to recover the core is on the sled beside the core. In the background is the support tower for a larger drill that can continuously recover cores to a depth of 1,000 meters. (Photograph by Kendrick Taylor.)
In This Issue
- Art
- Astronomy
- Biology
- Chemistry
- Communications
- Computer
- Engineering
- Environment
- Ethics
- Evolution
- Mathematics
- Medicine
- Physics
- Psychology
- Technology
Human Embryonic Stem-Cell Research: Science and Ethics
Shirley Wright
Biology Ethics
A discovery that could revolutionize medicine raises the question of where to draw the line on human embryonic research
The Mystery of Ticklish Laughter
Christine Harris
Biology Psychology
Pleasure or pain? Social response or reflex? Tickling and the laughter it induces are an enigmatic aspect of our primate heritage
Polarized Starlight and the Handedness of Life
Stuart Clark
Astronomy Biology Physics
The asymmetry of the amino acid molecules found in all living things may have originated in space billions of years ago
DNA Vaccines as Cancer Treatment
Edward Cohen, Morton Schatzman
Medicine
No longer limited to warding against infectious agents, vaccines may help treat diseases after they have been diagnosed
