LINKS TO GLOBAL DATA

Potential astronomical sites are of interest for ESO and other institutions in the frame of the site surveys for ELT class telescopes. These telescopes might have particular requirements excluding some of the best existing observatories (eg. seismology: the current OWL design cannot survive the earthquakes foreseen during the next 50 years in northern Chile). For this reason the first phase of the site survey shall be global: state of the art databases in meteorology, geography, seismology and climatology shall be merged to build a specific tool capable to extract all locations fulfilling a given set of minimum characteristics determined by the project. The validity of the underlying assumptions shall be demonstrated on existing observatories (eg: is climatology capable to explain the climate change of the last decade at Paranal?). The site extraction tool, a Geographical Information System (GIS) shall be used in the course of the OWL design phase to reflect the consequence of engineering and operation parameters onto the density of available sites and their relative quality. For example, if OWL can produce science ONLY when operated with adaptive optics assisted by laser guide stars, it will not work in slightly cloudy (so-called spectroscopic) sky because of the laser backscattering. Only in the last phase of the site survey should field measurements be conducted on a few selected sites. In this phase, data collected previously by other teams are of course of high interest provided that the instruments used are of acknowledged accuracy. See the summary power point presentation: "A Nest for OWL"

Cloud Cover

-World Cloud Cover and World Precipitable Water Vapour from Surface meteorology and Solar Energy Data Set (SSE) of NASA's Earth Science Enterprise Program (1x1 degree grid).

-ISCCP: INTERNATIONAL SATELLITE CLOUD CLIMATOLOGY PROJECT (280km equal-area grid, monthly, global)

-OLR study for the Paranal and Chajnantor area by R. Bustos, March 2001

Sub-tropical Jet Stream

-mean wind speed at 200mB for the months of June and December over the period 1980-1995 (source NCDC Global -2.5 degree- Gridded Upper Air Statistics).

Aerosols

-Satellite detection of mineral aerosols over land
by Nick Brooks

- Tropospheric Aerosols Over the Oceans by Rudolf B. Husar and Larry L. Stowe showing seasonal maps of the equivalent aerosol optical depth over the oceans (eg: Jun-Jul-Aug) derived routinely from operational meteorological satellites

-SeaWifs Project with sandstorm imaging capability

Sky Background

-The night sky in the world, a public web site based on The first world atlas of artificial night sky brightness, P. Cinzano, F. Falchi and C.D. Elvidge, MNRAS 2001, astro-ph/0108052.

Climate variability

-CLIVAR an international research program on climate variability and predictability.

-Evidence of Climate Change and Adverse Impacts in Africa

Intertropical Convergence Zone

-ITCZ (source NCDC bibliography)

-illustration.

South American Monsoon System (SAMS)

- 52 Years of Climatological Data for the Chajnantor Area by R. Bustos, Nov. 2000, with the PWV distribution during the period 1948-2000.

-Summer Climate over Chajnantor, by R. Bustos, June 2001

El Nino Southern Oscillation

-ENSO at ESO

-52 Years of Climatological Data for the Paranal Area using NCEP/NCAR re-analysis data, by R. Bustos, Nov. 2000 with annex, Dec. 2000

-A 15-year Cross-correlation analysis of NCEP/NCAR reanalysis data with Paranal Ground Stations, by R. Bustos, Jan. 2001 with Surface Temperature Anomalies for the period 1993-2001

-Climatological Analysis of Seeing Conditions at Paranal, Chile, by P. Casals and M. Beniston, August 2001.

The ESPAS LIBRARY contains data on particular sites of interest.

Send comments to <Marc.Sarazin@eso.org>
Last update: October 2000