___________________________________________________________________

Photograph by: Peter Somers
National Science Foundation

Texas A&M University and its partner organizations have been studying the temporal and spatial scales of human disturbance at McMurdo Station, Antarctica for several years. The objective is to design and implement a long term monitoring porgram to detect and quantiify human impacts in the McMurdo Station area in order to inform management decision making and document enviromental performance. A final report for the Pilot Project phase of the study is the culmination of a series of international workshops, a year of planning activities and report writing, and a three year pilot project.

Photograph by: Dave Bresnahan
National Science Foundation

Final Report - antarctic_final.pdf

The goal was to rigorously test the design elements of a long term monitoring program to be implemented at McMurdo Station. The objective of long term monitoring is to observe and quantify impacts caused by science and support operations. The monitoring system is designed to accurately describe the status and the trends in environmental condition in support of environmental management and decision making. The design of the long term monitoring program is based on historical information as well as data collected during the pilot project. During the pilot project the terrestrial and marine settings at McMurdo Station were intensively sampled. A “phased-in” approach allowed resources to be concentrated on defining the attributes of specific components of the system each year. During the first year the terrestrial (land) setting was targeted for intense sampling. The second field year included a revised sampling plan for the terrestrial setting based on the first year results and an initial sampling of the marine setting. In the third year both the terrestrial and the marine sampling plans were revised based on the previous year’s results and to test any remaining program design assumptions. A number of variables were measured including physical (surface disturbance, grain size, carbon content), chemical (PCBs, metals, and hydrocarbons) and biological (benthic community structure) indicators of impact. More than 2000 samples were taken over the term of the project providing the data needed for a robust statistical assessment of the monitoring program’s design elements.

Photograph by: Kristan Hutchison
National Science Foundation

In most locations at McMurdo Station contamination is minimal, however there are legacies from previous practices (particularly in Winter Quarters Bay) and areas where activities create the opportunity for on-going contamination ( i.e., hydrocarbon spills at the fueling station and the helicopter pad). In all cases these “heavily impacted” areas are patches that are meters or less in size. There are few, if any, biological resources in the terrestrial setting that are at risk of exposure to contaminants. The most severe contamination is the PCB, hydrocarbon and trace metal legacy of disposal practices in Winters Quarters Bay. However, even in Winter Quarters Bay, the distribution of contaminants is patchy and localized. Physical disturbance was quantified from aerial photography. Disturbed surfaces essentially cover the entire confines of the station. This pattern of surface disturbance wasestablished early in the station’s history. All data collected were statistically analyzed to recommend the elements of a long term monitoring program including the indicators to measure, the density and frequency of sampling, and the basis for site selection (fixed point versusprobabilistic).

Photograph by: John J. Weaver
National Science Foundation

The first goal of the project was to identify the “footprint” of the station. The definition of the “footprint” is critical in determining its spatial extent in a quantitative manner. There are multiple “footprints” (air quality, TPH, trace metals, physical disturbance, etc.) that can be detected and quantified. There is an inference in the concept of a “footprint” that the disturbance is relatively uniformly distributed over some area and that the intensity of the disturbance decreases in a regular fashion (often assumed to be linear or logarithmic) with distance from the origins of the disturbance. However, the situation at McMurdo Station is more often.... FOR MORE DETAILS SEE THE ENTIRE FINAL REPORT at antarctic_final.pdf