Satellite-derived SST data as a proxy for water temperature in nearshore benthic ecology

Satellite-derived sea surface temperatures (SSTs) are increasingly being used as a proxyfor water temperature in nearshore marine ecology, but there have been very few evaluations of howaccurately SSTs reflect actual temperatures experienced by subtidal organisms. Here, we describethe benthic temperature climatology of 4 coastal locations along a ~1000 km latitudinal gradient inocean temperature in Western Australia (WA), and compare temperature records from in situ loggersat 10 to 12 m depth with records from 2 independent satellite-derived SST datasets over 2 years.Satellite-derived SSTs were significantly correlated with in situ logger data at all locations, whichdemonstrate their overall ability to detect general patterns of ecological importance. However, SSTswere also significantly different from benthic water temperatures (usually 1 to 2°C higher), and theydid not adequately detect ecologically important small-scale variability or provide reliable informationon temperature extremes. Furthermore, rank orders of the study locations differed between themethodologies, especially in winter. We emphasize the need to carefully consider whether the accuracyand resolution of satellite-derived SSTs are appropriate for the specific ecological hypothesisbeing tested in nearshore subtidal habitats, and advocate the use of in situ loggers otherwise. We alsohighlight the suitability of the WA coastline for experimental work on the effects of temperature (andsynergistic factors) on marine organisms.