Trends in the Spring Breakup Dates Within the National Petroleum Reserve-Alaska

Abstract:

The National Petroleum Reserve in Alaska (NPR-A) is a vast area of approximately 23 million acres and it extends from the north side of the Brooks Range to the Arctic Ocean. The Bureau of Land Management (BLM) installed seven gauging stations, starting in 2003, to establish baseline conditions for weather and hydrological variables. These stations are equipped with sensors capable of tracking water level and temperature changes in the streams, air temperature, wind speed and direction, and rain fall. This work covers the entire record of water level changes at each station during spring breakup and focuses on first flow dates, which could reflect changing weather conditions in the area. Observed trends indicate a general tendency to early breakup dates in the region. Some of the available data point out a change of nearly two weeks in the breakup date. Additionally, the tendency to early breakup seems to be accentuated in recent years.