THE PERIOD OF INTENSIVE OBSERVATION IN THE GAME STUDY AREA, THE VICINITY OF YAKUTSK, IN THE CONTEXT OF LONG-TERM CLIMATIC VARIABILITY
Fedorov, Alexander (1)
(1) Melnikov Permafrost Institute, Russian Academy of Sciences
The paper discusses the present-day environmental changes in the Spasskaya Pad study area over the period 1996-2000 in respect to long-term variations in the climate and the near-surface permafrost of Central Yakutia. The study area is situated 24 km north-north-west of Yakutsk. An integrated permafrost-landscape research program has been performed here since 1996, including compilation of maps and inventories of the basic environmental elements. The main component of the program is monitoring of changes in the temperature and moisture regimes of soils and in the active layer thickness.
A retrospective scheme of the permafrost-landscape evolution in Central Yakutia over the last 60-70 years was constructed. Based on weather records, schemes of variations in mean annual, summer and winter air temperatures and precipitation, mean annual soil temperatures at 1.6 and 3.2 m depths, and depth of seasonal thaw were developed. A dendrochronological model for the Spasskaya Pad area and a generalized model for Central Yakutia were constructed. The data obtained from Spasskaya Pad were analyzed in the context of these schemes.
The period of observation (1996-2000) was characterized by a significant increase in air temperature. Departures from the long-term average (the period of instrumental observations) were +1.3C for the mean annual temperature, +2438C/day for the winter temperature, and +581C/day for the summer temperature. The annual precipitation was 8 mm lower than the long-term average. It should be noted however that the precipitation in the 1996-2000 period was 19 mm higher than the mean of the last 30 years.
Therefore the period of intensive observation in the GAME study area, Central Yakutia, may be regarded as non-typical and quite different from the overall trend in landscape evolution. However, a cyclical nature of landscape development was not disrupted, as evidenced by both meteorological records, and dendrochronologic and geocryological data from Spasskaya Pad.
By and large, the period of intensive observation for GAME coincided with the phase of relatively large increase in air temperature and decrease in precipitation in Central Yakutia.
Submittal Information
Name :
Date :
Fedorov, Alexander
30-May-01-18:43:39
Organization :
Theme :
Melnikov Permafrost Institute, Russian Academy of Sciences
