Sandy clues to ancient climate.The orientation of these dunes in north-central Nebraska provide a clue that the climate there a millennium ago was much different than it is today. The Nebraska Sand Hills have been frozen in place by vegetation vegetation /veg·e·ta·tion/ (vej?e-ta´shun) any plantlike fungoid neoplasm or growth; a luxuriant fungus-like growth of pathologic tissue. for 800 to 1,000 years, says David B. Loope, a geologist at the University of Nebraska in Lincoln Lincoln, city and district, England Lincoln, city (1991 pop. 79,980) and district, Lincolnshire, E England, in the Parts of Kesteven, on the Witham River. . The 12-to-15-meter-tall dunes, which run from west-northwest to east-south-east, couldn't have been formed by modern wind patterns, which bring plant-nurturing moisture to the region from the Gulf of Mexico Noun 1. Gulf of Mexico - an arm of the Atlantic to the south of the United States and to the east of Mexico Golfo de Mexico Atlantic, Atlantic Ocean - the 2nd largest ocean; separates North and South America on the west from Europe and Africa on the east in the springtime. Loope and his colleagues report in the July 21 Science that to build the dunes 1,000 years ago at the beginning of the so-called Medieval Warm Period Medieval Warm Period n. The period from about 1000 to 1400 in which global temperatures are thought to have been a few degrees warmer than those of the preceding and following periods. , much drier spring winds must have blown in from the southwest. |
|
||||||||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion