Researchers found that vibrations recorded on September 11 were of a low magnitude, too small to cause structural damage. The collapse of the towers was attributed to the interaction between the ground and building foundations, transmitting energy from the impacts and collapses.
The study reveals that new graduates spend less time looking for work, with most finding jobs within the Earth and space sciences. The majority are engaged in research, with many reporting high job satisfaction due to intellectual challenge and opportunities for continued learning.
Satellite data confirms that plant life above 40 degrees north latitude has been growing more vigorously since 1981, with Eurasia showing more pronounced greening than North America. The existing vegetation has increased in density, but the area of vegetation has not extended.
Studies of the Eastern California Shear Zone reveal significant temperature and heat flow differences between sides of a strike slip fault, leading to unequal ground movement during earthquakes. This discovery provides a more accurate method for modeling earthquake data, allowing computer models to better fit ground reality.
The American Geophysical Union and the American Geological Institute conducted a survey of recent Ph.D. graduates in earth sciences, revealing significant shifts in job prospects and postdoctoral positions. 80% of geoscience Ph.D.s found jobs in the geosciences, with negligible unemployment rates compared to previous years.
Dr. Baerbel K. Lucchitta's research finds that some Martian outflow channels display similar characteristics to those on the Antarctic sea floor, carved by ice streams. The study suggests an ancient ocean may have existed in Mars' northern plains.
The American Geophysical Union has named Robert C. Cowen its award for sustained achievement in science journalism, recognizing his 50-year career as a science writer and editor at The Christian Science Monitor. The award honors Cowen's contribution to the public understanding of science.
The American Geophysical Union is hosting its Fall Meeting, featuring a range of scientific sessions and press conferences. Press registrants include over 60 journalists from major publications, covering topics such as climate change, natural hazards, and space exploration.
The American Geophysical Union is seeking nominations for the 2001 Sullivan and Perlman Awards, which recognize outstanding reporting in science journalism that makes geophysical science accessible to the general public. Nominations must be submitted by January 13, 2001.
Researchers at MIT found that urban air pollution will not have a big effect on global temperature change, with some regional effects possible. The study used a new method to couple urban air chemistry models with global climate models, allowing for more accurate predictions.
New studies using satellite imagery reveal El Niño's disruption of the marine ecosystem, with a reduction in phytoplankton and an increase in nutrient-depleted waters off Baja California. The findings suggest that warm waters ushered in during El Niño resulted in a decline in phytoplankton, which are crucial for the ocean's food chain.
The American Geophysical Union Fall 2000 meeting will take place at the Moscone Convention Center in San Francisco from December 15 to 19. Press registrants can access scientific sessions, the Press Room, and Briefing Room with a valid badge.
A NASA scientist has solved the century-old mystery of the Chandler wobble, attributing it to fluctuating ocean pressure changes. The study found that two-thirds of the wobble is caused by these changes, while one-third is attributed to atmospheric fluctuations.
A new study by Dr. Laurie A. Leshin found that the crust of Mars may hold two to three times more water than scientists had previously believed. The research compares the amount of deuterium in a meteorite with the Martian atmosphere, suggesting that significant groundwater reservoirs currently exist on the planet.
Research suggests that rising CO2 levels may cause a 40% reduction in coral reef growth over the next 65 years. The team found no evidence of acclimation to reduced carbonate levels, highlighting the negative impact on coral reefs. This finding has significant implications for the increasing vulnerability of many reefs to other stressors.
Alexandra Witze and Richard Hill win AGU journalism awards for their investigative stories on the Kerguelen Plateau and earthquake forecasting in Oregon. The awards recognize excellence in science writing and honor the scientists who inspired their work.
The American Geophysical Union has made the Spring Meeting abstracts and session information available online. Reporters can search for papers of interest using parameters such as scientist name, institution, geographic location, and topic. Press conferences are also being organized to cover significant scientific news.
Detecting active regions on the far side of the Sun allows for up to two weeks' advance warning of strong solar winds. The method uses Lyman alpha radiation to track sunspot activity and predict severe space weather.
Scientists have discovered a new mechanism for coronal mass ejections, which are large-scale eruptions on the Sun that can cause geomagnetic storms and disrupt power generation. Shock waves generated by solar flares in other regions of the sun can cause these eruptions, contrary to previous thought.
The American Geophysical Union's 2000 Spring Meeting will feature a wide range of scientific sessions and press conferences on cutting-edge research. The conference will be held May 30 to June 3 at the Washington Convention Center, with special focus on interdisciplinary collaboration.
Researchers at NOAA's National Climate Data Center found evidence that the rate of global warming is accelerating, with recent record high temperatures surpassing expectations. The study analyzed data from 1997 to 1999 and concluded that the rate of warming since 1976 is greater than previously predicted.
The 1999 Fall Meeting featured press conferences on climate change, solar activity, and Mars exploration, as well as new discoveries in India and Antarctica. A digital library for Earth science education was also unveiled, providing rapid access to high-quality information.
Scientists have reported a striking decline in Arctic sea ice thickness since the 1960s, with an average reduction of 4.3 feet. The study analyzed data from three autumn cruises and found a perennial ice cover of 1-3 meters, significantly thinner than previous estimates.
The American Geophysical Union has established a new journalism award to recognize the work of science writers covering news stories. The David Perlman Award will honor writers who produce high-quality news stories in various media outlets.
The American Geophysical Union's Fall Meeting features a press field trip on San Francisco Bay, where USGS scientists discuss water resources research. Media representatives can attend scientific sessions, visit the Press Room and Briefing Room, and participate in exclusive events.
Researchers have found that smoke from forest fires practically shuts off the 'warm rain' processes that create rain in tropical clouds. The cloud tops must grow above the freezing level for an alternative mechanism to start producing rain. This study, based on TRMM data, provides direct evidence of the impact of smoke on rainfall.
Researchers attribute decrease in atmospheric carbon monoxide levels to reductions in manmade emissions, consistent with trends reported by the EPA. The study found a significant decrease of around five parts per billion by volume in carbon monoxide concentration levels at Big Meadows in Shenandoah National Park, Virginia.
The American Geophysical Union will host two major scientific meetings in 1999 and 2000, covering a range of earth and space sciences topics. The 1999 Fall Meeting in San Francisco will feature newsworthy presentations on hydrological issues and special sessions on biogeosciences and education.
A study found that African dust is a major factor affecting southeast U.S. air quality, with up to half of breathable particles in the air originating from Africa. The dust can push total airborne particles above the EPA's Clean Air Act limit on certain days.
German scientists used a climate model to conclude that the Sahara's desertification began abruptly 5,440 years ago due to subtle changes in Earth's orbit. The resulting desertification had significant impacts on ancient civilizations, with some of the most severe changes occurring between 4,000 and 3,600 years ago.
A new study predicts that jet contrails will become a significant climate factor by 2050, causing a warming of the Earth's atmosphere. Contrails are expected to increase in coverage over Europe and Asia, with potential temperature increases reaching up to 0.7 watts per square meter.
The AGU Spring Meeting will feature new press conferences on Leonid Meteors, which created a temporary lunar atmosphere, and Yucca Mountain as a potential site for long-term nuclear waste storage. The sessions will also include discussions on Mars Global Surveyor findings and the impact of magnetic storms on Earth.
A new study reveals that global surface temperatures have increased by 14.6 degrees Celsius, with the warmest years on record occurring in the 1990s. Most of the warming has occurred over the northern continents during specific seasons.
A worldwide study of the Sun's quiet period reveals insights into solar activity and its effects on Earth. The research, published in the Journal of Geophysical Research, explores the Sun's large-scale, stable structures that dominate the solar corona at solar minimum.
The American Geophysical Union Spring Meeting 1999 featured various scientific sessions and press conferences, including briefings on Mars Global Surveyor results, Yucca Mountain nuclear waste storage, and the South China Sea Monsoon Experiment. The event took place from June 1-4 at Boston's Hynes Convention Center.
The Mars Pathfinder mission sent back 2.3 gigabits of new data, including over 17,000 images and 16 chemical analyses of rocks and soil. The mission provided key findings on Mars' geology, magnetic properties, atmosphere, and cartography.
David Sington has won the 1999 Walter Sullivan Award for Excellence in Science Journalism, presented by the American Geophysical Union. The award recognizes his work on the eight-part television series "Earth Story," which explores fundamental processes shaping the Earth and its interaction with climate and evolution.
Scientists have developed a new method to study sprites, the high-altitude companions of lightning strikes, using radio signals. By analyzing these signals, researchers can now estimate the number of sprites spawned by a single thunderstorm with greater accuracy.
Dr. Jeanne Sauber will present a lecture on the earthquake hazard in Alaska, studying subduction from space, at the National Science Teachers Association convention in Boston. She will discuss direct measurements of subduction using space-based data and its implications for Alaskan plate movement.
AGU's Spring Meeting will address pressing issues such as climate change, nuclear waste management, and the impacts of global variability. The event will feature a diverse range of special sessions and press conferences.
Researchers found that the 20th century warming counters a 1,000-year-long cooling trend and reversed a medieval warming period. Temperatures in the latter half of the 20th century were unprecedented, with human-induced greenhouse gases being a major factor.
The AGU Book 'New Perspectives on the Earth's Magnetotail' provides first-hand information on energetic particles and reveals basic properties of plasma in the universe. Edited by top experts, it offers a basis for understanding cosmic processes and auroral/geomagnetic phenomena.
17-year-old Sasha Jones won a contest to name the first Earth Observing System satellite, Terra, which will study global climatic changes. The satellite's launch is set for July 15, 1999, and will enable new research into the planet's climate system.
A record-breaking Arctic polar vortex in 1996-1997 led to significant ozone depletion, comparable to the Antarctic's early 1980s levels. The study revealed that chemical interactions between nitric oxide and nitrogen dioxide chemistry played a crucial role in the depletion.
Scientists Dr. Jeffrey R. Johnson and colleagues developed a helium-3 map of the Moon based on factors like exposure age, solar wind, and titanium content. The greatest amounts of helium-3 are expected to be found on the far side maria and in nearside areas with high concentrations of titanium dioxide.
Yale researchers develop a hypothesis linking rock metamorphism and earthquake generation. They show that rapid release of water from rocks within fault zones can lead to high internal fluid pressures, decreased rock strength, and induced rock failure, potentially triggering repeated earthquakes.
The American Geophysical Union's Fall Meeting will take place from December 6-10 at the Moscone Convention Center in San Francisco. Media representatives can register in advance to receive an abstract volume and attend press conferences, with a special excursion planned for December 5.
Researchers at Berkeley's Space Sciences Laboratory have concluded that atmospheric holes in satellite imagery are caused by instrument noise, not small comets. The study analyzes raw data from the Polar spacecraft and shows that dark pixel clusters are consistent with instrumental noise.
A new volume of research explores the physical processes and interactions of Antarctic sea ice, shedding light on its differences from Arctic sea ice. The study highlights the importance of interdisciplinary approaches to understanding this complex environment, which is sensitive to climate change.
Researchers have assembled 20 articles to study interactions at the Antarctic Continental Margin, presenting new techniques and expanding year-round measurements. The volume includes a bathymetric chart of the southern Weddell Sea, providing insights into longer-term cycles.