’Strapped in’ by wing dykes
The oldest data available on the Missouri River – from the logs of Lewis and Clark – show that water flow on the river today is far more variable than it was 200 years ago. The data also show that the river is some 220 yards narrower at St. Charles, Mo., today at 500 yards across than in 1804 when it spread out some 720 yards.
These changes are due to modifications of the river by the Army Corps of Engineers, say Robert Criss, Ph.D., pro
ESA’s Proba satellite here shows a winding segment of the 7240-km long Great Wall of China situated just northeast of Beijing. The Great Wall’s relative visibility or otherwise from orbit has inspired much recent debate.
The 21 hours spent in space last October by Yang Liwei – China’s first ever space traveller – were a proud achievement for his nation. The only disappointment came as Liwei informed his countrymen he had not spotted their single greatest national symbol from
If rising global temperatures cause the ice streams of Western Antarctica to break up, major cities and agricultural heartlands the world over would be submerged. Researchers from the University of Leeds’ School of Geography are set to embark on a £1m, three-year project to find out exactly how stable they are.
The project, the biggest of its kind to date, will drill up to 2.2km down into the Rutford ice stream in Western Antarctica to determine its stability and see how close it is to break
IRD scientists have revealed, in an article just published in Nature, that the cooling event known in the Northern Hemisphere as the Younger Dryas (about 12 000 years B.P.) was expressed in the Pacific by the absence of any South Pacific Convergence Zone activity and the movement of tropical waters closer to the Equator. This observation shows the interaction which occurs between the low and high latitudes and provides boundaries relevant for building ocean-atmosphere climatic models. Geochemical ana
Scientists at Bristol University have established the time when mountains first became forested. The timing of upland ‘greening’ has major implications for understanding global temperatures in the past, and will help refine models of present-day climate change.
A unique assemblage of giant fossil trees has been found in 300-million-year-old rocks in Newfoundland, Canada, by Dr Howard Falcon-Lang of Bristol University’s Earth Sciences Department. The fossilised trees represent the oldest upla
Plankton appear to play a major role in regulating the global climate system, according to new research
David Siegel, professor of geography at the University of California, Santa Barbara, and director of the Institute for Computational Earth System Science, made the discovery with his former Ph.D. student Dierdre Toole, who is now based at Woods Hole Oceanographic Institute.
In an article in the May 6 issue of the journal Geophysical Research Letters, the scientists explai
For years the debate about climate change has had a contentious sticking point – satellite measurements of temperatures in the troposphere, the layer of atmosphere where most weather occurs, were inconsistent with fast-warming surface temperatures.
But a team led by a University of Washington atmospheric scientist has used satellite data in a new and more accurate way to show that, for more than two decades, the troposphere has actually been warming faster than the surface. The new approach
University of Leicester scientists have made a unique discovery at an Atlantic island popular with British holidaymakers.
They have uncovered giant sand dunes on Tenerife that tell a tale of terrifying destruction in ancient times, when fiery clouds swept right across the island, leaving very little in their wake.
Volcanic islands – volcanoes whose summits poke out of the oceans – make popular holiday destinations, like Madeira, Hawaii and the Azores. Some, like Hawaii, erupt lava f
Think of ESA’s Proba as the little satellite that does a lot. It is only the size of a washing machine but its main instrument – the smallest hyperspectral imager ever flown in space – has an expanding portfolio of uses encompassing agricultural mapping, water quality monitoring, charting forest fire damage and disaster management.
Launched in October 2001, the Project for Onboard Autonomy (Proba) satellite measures just 60 x 60 x 80 cm. Its main instrument takes up around a third of t
The Younger Dryas period, about 12 000 years ago, was marked by a sharp cooling event in the Northern Hemisphere. Temperatures there fell by between 2 and 10°C. The East Antarctic in contrast experienced an episode of warming. Data have up to now been insufficient or too inconclusive to enable palaeoclimatologists to track this climatic event in the southern temperate regions and the tropics. An IRD researcher campaign took a 2 m drill core sample from the isle of Espiritu Santo, Vanuatu, found to co
Something is missing in the analysis of emissions of volatile organic compounds from a Michigan forest, and, according to a team of atmospheric scientists, what they do not know can have a large impact on air pollution in areas in and near forests.
“Organic compounds emitted by some trees play a role in ozone and aerosol production in the lower atmosphere,” says Dr. William H. Brune, professor of meteorology and head of Penn State’s department of meteorology. “It appears that, at least
An earthquake shook the South-West Pacific islands of Ambrym and Pentecost on 26 November 1999. It was the strongest thrust event ever recorded in central Vanuatu. Offshore and onshore data gathered by IRD researchers yielded clues as to the tectonic movements involved in the earthquake. A resulting model of the rupture mechanism showed that in this area of Vanuatu, slipping motions of the Australian oceanic plate under the Pacific plate are blocked to the West, which generates strong stresses to the
The first solid evidence of human use of fire in Eurasia as early as 790,000 years ago has been found in excavations in Israel conducted by the Hebrew University of Jerusalem Institute of Archaeology.
The discovery was made in excavations, which have been conducted over seven seasons, at the Benot Ya’aqov bridge site along the Dead Sea rift in the Hula Valley of northern Israel. According to Prof. Naama Goren-Inbar, head of the Institute of Archaeology and director of the Benot Ya’aqov exc
“Regime shifts” are infrequent, large changes in oceanic conditions that spread through the food web. Depending on dynamics of the ecosystem, the response of a biological organism to some external forcing can be smooth, abrupt, or discontinuous.
In a paper published in the current issue of Progress in Oceanography, Dr. Jeremy Collie, University of Rhode Island Graduate School of Oceanography, Dr. Katherine Richardson, University of Arhus, Denmark, and Dr. John Steele, Woods Hole Oceanograph
Scientists at the National Space Science and Technology Center (NSSTC) in Huntsville, Ala., are using information gleaned from NASA satellites, aircraft and field research to better understand dynamics behind tornadoes, lightning, hurricanes and other destructive forces of nature.
“A better understanding of severe weather can help people year-round,” said Dr. Tim Miller of the Global Hydrology and Climate Center (GHCC) in Huntsville. “The Center is conducting a variety of unique research pr
The ornate map, seemingly crude by today’s standards, depicts sea monsters off the coast of Scotland, sinking galleons, sea snakes, and wolves urinating against trees.
When oceanographers from Plymouth Marine Laboratory and the University of Rhode Island compared a large group of swirls, shown on the chart off the east coast of Iceland, with thermal images from an Earth observation satellite they found the swirls corresponded almost perfectly with the Iceland-Faroes Front – where the Gulf
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