UAF researchers say ANWR snow conditions would pose challenges
Click here to go to the full PDF version of this issue, with any maps, photos or other artwork that appears in
some of the articles.
for Petroleum News
A research team from the University of Alaska Fairbanks Geophysical Institute has published a report on the results of research into snow conditions on the coastal plain of the Arctic National Wildlife Refuge. The teamís findings point to significant differences between the snow conditions in ANWR and conditions farther west on the coastal plain. These differences will likely require changes in the way oil and gas explorers conduct off-road winter transportation, when conducting activities in ANWR, the researchers suggest.
In particular, strong winds in the ANWR region tend to blow snow into drifts on the lee sides of river and stream-cut banks, leaving relatively thin snow cover on plateaus and other flatter areas. Thus, the overall snow cover tends to be thinner than in state lands to the west and in the National Petroleum Reserve-Alaska.
Field researchIn research conducted since 2014, the UAF team assessed winter snow conditions on the ANWR coastal plain using ground measurements of snow depths and densities combined with aerial photogrammetric mapping. In 2018 and 2019 the team mapped about 200 square kilometers of the 1002 area in April, at around the time of peak snow depth. The mapping confirmed the wind-blown nature of the snow cover and showed remarkably consistent snow patterns, despite significant differences in the amount of snowfall in each of the years. However, with relatively less snow in 2019 compared with 2018, the average snow depth in wind-scoured areas was less in 2019 than in 2018, while the snow drifts were similar in horizontal extent.
Snow roads neededIt is likely that winter transportation across wind-scoured areas will require the building of snow roads to protect the underlying tundra, the researchers suggest. And, since there are fewer lakes in ANWR than farther west, there will be issues regarding the use of water in snow road construction, potentially driving a need for new construction techniques. On the other hand, it may prove possible to use snow from the deep drifts when building snow roads, the researchers say.
New technologies, in particular high precision mapping from aircraft, have the potential to help in the planning for off-road transportation on the coastal plain, the UAF report says. But, the mapping of snow thicknesses as a precursor to planning off-road access requires mapping of the land surface before the winter snow arrives - subsequent mapping after the snow has fallen would then provide data concerning snow cover thicknesses. However, the researchers cautioned that the snow cover tends to build up over time during the winter, perhaps leading to maximum snow cover in February or March.
The report suggests that these considerations would likely apply to any on-land exploration activities planned for the winter season of 2019-20.
- ALAN BAILEY