The MODIS marine chlorophyll a product provided, similar to SST, is a 4 km global monthly composite based on smaller resolution daily imagery compiled by NASA. The imagery is reliant on clear ocean (free of clouds and ice) so only months from March to October have been provided, as the chlorophyll levels in the Arctic diminish during the winter months, when sea ice is prevalent. The marine chlorophyll a is measured in mg/m3

This data set includes information on sampling locations, water chemistry and chlorophyll collected at 18 locations in the Great Lakes-St. Lawrence River and 4 locations in Lake Simcoe.

The Lake Simcoe lake monitoring program provides measurements of chemical and physical water quality limits such as total phosphorus, nitrogen, chlorophyll a, pH, alkalinity, conductivity, dissolved organic and inorganic carbon, silica, other ions, water transparency, temperature and dissolved oxygen. Samples are collected biweekly during the spring, summer and fall. *[pH]: potential of hydrogen