On 24 July 2008, a glacier lake outburst flood
(GLOF) occurred at the western (w-) Zyndan glacier lake
in the Tong District of Ysyk-Kol Oblast, Kyrgyzstan. The ¨
flood killed three people and numerous livestock, destroyed
infrastructure, and devastated potato and barley crops as
well as pastures. Tuurasuu village and a downstream reservoir
on the Zyndan river escaped heavy damage because
the main flood was diverted toward the Tong river. RTKGPS
and satellite data (Landsat 7 ETM+, ALOS/PRISM, and
ALOS/AVNIR-2) reveal that the flood reduced the lake area
from 0.0422 km2
to 0.0083 km2
, discharging 437 000 m3 of
water. This glacier lake was not present in a Landsat 7
ETM+ image taken on 26 April 2008. It formed rapidly over
just two and half months from early May to the late July,
when large amounts of snow and glacier melt water became
trapped in a basin in the glacier terminus area, blocked by
temporary closure of the drainage channel through the terminal
moraine that included much dead-ice. In the same
mountain region, most other glacier-lake expansions were
not particularly large during the period from 1999–2008. Although
events like the w-Zyndan glacier lake outburst occur
infrequently in the high Central Asian mountains, such fast
developing, short-lived lakes are particularly dangerous and
not easy to monitor using satellite data. Appropriate measures
to protect against such lake outburst hazards in this
region include educating residents on glacier hazards and
monitoring techniques, providing frequently updated maps
of glacier lakes, and planning and monitoring land-use, including
house locations.