摘要:

Just after Election Day, the Mars Global Surveyor spacecraft (Figure 1) will embark on a journey to Mars to examine the surface and the seasonal variations of the atmosphere over an entire Mars year. Mars is an extremely rich mission target because the scientific questions it poses touch on geology, geophysics, geochemistry, atmospheric physics, climatology, biology, and—most of all—comparative planetology.Researchers will use data collected from this mission to compare the planet's formation and evolution with that of Earth, to understand the evolution of climate and water on Mars, and to determine if life has ever existed on Mars. Mars Global Surveyor will acquire a basic global understanding of the planet as it exists today, provide a framework for understanding its past, and help shape a series of small missions to Mars that are being planned for the next 10 ye

ISSN:0002-8606    

DOI:10.1029/96EO00295

年代:1996

数据来源: WILEY

摘要:

The Colorado River will never be the same. Declaring success in the controlled flooding experiment conducted on the river in April (Eos, June 11), U.S. Secretary of the Interior Bruce Babbitt has officially changed the operation plan for the Glen Canyon Dam in order to better protect the natural resources of Grand Canyon National Park and Glen Canyon National Recreational Area.In a ceremony on October 9 in Phoenix, Arizona, Babbitt completed a process that began during the Bush Administration. In 1989 researchers and land managers began preparing an environmental impact assessment of how the river and dam could be managed to better protect the ecosystem. The new “record of decision” signed by Babbitt directs the Department of the Interior to operate the dam in “such a manner as to protect, mitigate adverse impacts to, and improve the values” for which the parks were established. The order makes permanent some changes first ordered in 1991; those changes allow for (but do not necessarily prescribe) occasional controlled floods and other dam management procedures that minimize erosion dow

ISSN:0002-8606    

DOI:10.1029/EO077i045p00442-02

年代:1996

数据来源: WILEY

摘要:

Seventy Earth scientists from Europe, North America, and Australia gathered in Lyon, France, from March 28 to 30, 1996, to make plans for developing an Earth reference model for geochemical budgets and fluxes between different reservoirs in the Earth. The Geochemical Earth Reference Model (GERM) Workshop brought together a diversity of geochemists working on Earth systems, from core to atmosphere. Sessions began with keynote speeches that covered a range of issues related to characterizing various reservoirs and a statement of what we know about element budgets and fluxes. Following the speakers, there were general discussions of issues and brief presentations by other participants. Topics ranged from the deep mantle to mid‐ocean‐ridge budgets to the cycle of carbon and other volatile compone

ISSN:0002-8606    

DOI:10.1029/96EO00298

年代:1996

数据来源: WILEY

摘要:

The budget process for the 1997 fiscal year started 6 weeks late, but with U.S. federal elections looming and bad memories from fiscal 1996 lingering, it ended on time. An analysis of appropriations for science agencies and programs funded by the U.S. government reveals that while scientists' fears of massive budget cuts never materialized, overall levels of funding for research remained flat. The tables below show modest increases for many science programs, but most of those increases are offset by inflation, which has averaged about 2–3% per year for the past several year

ISSN:0002-8606    

DOI:10.1029/96EO00300

年代:1996

数据来源: WILEY