Modeling Surface Photosynthetic Active Radiation in Taylor Valley, McMurdo Dry Valleys, Antarctica

TitleModeling Surface Photosynthetic Active Radiation in Taylor Valley, McMurdo Dry Valleys, Antarctica
Publication TypeThesis
Year of Publication2016
AuthorsAcosta, DR
Secondary AuthorsBerkelhammer, M
Academic DepartmentEarth and Environmental Sciences
UniversityUniversity of Illinois at Chicago
CityChicago, IL
Thesis Typemasters
Keywordsdigital elevation model (DEM), geographical information system (GIS), ice-covered lakes, meteorological data, R model

Understanding primary productivity is a core research area of the National Science Foundation’s Long-Term Ecological Research Network. This study maps surface Photosynthetically Active Radiation (PAR) using long term data collected by a meteorological network in the McMurdo Dry Valleys. Four stations with ~20 years of records were used to correct T-sPAR, a topographic surface PAR model. Maximum expected daily surface PAR at meteorological stations was calculated for Taylor Valley, through statistical analysis of location records using a local regression model that included 84% of all observations. Expected values represent daily surface PAR under cloudless conditions. Daily measured and expected PAR was used to model cloud coverage at each location, corroborating that overcast conditions are positively correlated with proximity to the ocean. Ground-truth data collected for TaylorValley’s major lakes during the 2015/2016 field season were used to validate T-sPAR estimates. The final model approximates total seasonal surface PAR for the Taylor Valley basin. Bi- monthly maps estimate total surface PAR by lake to assist in future sampling site selection. Finally, a user interface was developed to estimate total daily surface PAR by coordinate or surface based on a user input date.