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What's new with UMass weather stations in Bolivia

November 2001
     In mid-October of 2001, and again a month later, Carlos Escobar and his team attempted to reach the Illimani station, to recover data and remove the equipment. In both cases, the station could not be located - due to burial by snow. There is no doubt that La Nina episodes result in anomalous snowfall on this mountain!

11 October 2000
     After four years of continuous measurements, the Sajama station was disassembled and removed from the mountain. Although still functioning, the mast was beginning to tilt due to glacier flow, and the accuracy of measurements was being compromised. Scientific research funding typically extends for 3 year intervals, so we were fortunate in being able to keep the Sajama AWS operating longer.
     We intended to also recover the Illimani station following the Sajama expedition, but the continuing La Nina made an October ascent impossible.

26 July 2000
     The pace of analysis is picking up. Sajama snow depth sensor data (rather noisy) have now been processed, yielding a composite record of snow accumulation and ablation at the station. Considerable annual variablity can be seen in both snowfall amount and the degree of subsequent scour.

18 October 1999
     Both stations are back 'on the air'! Between mid-September and mid-October expeditions occurred to raise up the sensors, perform repairs, and study the snowpack at each site. Data were recovered, which we expect to provide continuous weather records from both sites -- a great relief! Accompanying us for all or part of this work were Mark Williams and Eran Hood (Univ. of Colorado) and Ray Bradley (also UMass). Carlos Escobar and Nuevos Horizontes again provided invaluable logistical support, and this year organized a Conferencia (scientific talk) for us at the Bolivian Academy of Sciences. This was well-attended, and great fun for us.
     The weather on the Altiplano during the expeditions was not typical of September, and instability resulted in convection, lightning, and snowfall. However, excepting a slab avalanche 'way too close' to the Illimani site, the work was completed without incident. (A similar avalanche a few days earlier in the Cordillera Apolobamba had tragic consequences. Bolivian Times obituary and account.)

28 June 1999
     Telemetry continues from Illimani, but data will not be available until October (we need to adjust the time, due to the low voltage problem during the wet season). Images of the site from 17 June are available from the Images page -- Thanks to Carlos Escobar.

10 May 1999
     Finally, monthly data are now available from the data page. Illimani saw considerable snowfall during January, and enough snow and ice accumulated on the solar panel to drop the battery voltage below the threshold for transmission. Thanks to Carlos Escobar of Nuevos Horizontes for his efforts to restore telemetry. We are currently not receiving telemetry from Sajama, so planning in underway to fix the problem in September.

1 October 1998
     Today marks two years since the Sajama station was installed, an appropriate date to launch the website re-organization. We are very excited about the continuing high quality of the data, and progress is being made on understanding the climatic significance of geochemical variations in the snow. Also, there were significant differences between the two years in terms of temperature and precipitation, which will be presented here shortly -- check back soon!

21 August 1998
     As you will notice, there has been little new material added to this website within the past 12 months. However, both stations continue to function very well and are providing very interesting information about the climatic conditions on these mountains. By mid-September, this entire website will be completely reorganized and updated.

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Climate System Research Center | Department of Geosciences | University of Massachusetts

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Last updated: 28 March 2008