Global map of solid Earth surface heat flow

A global map of surface heat flow is presented on a 2° × 2° equal area grid. It is based on a global heat flow data set of over 38,000 measurements. The map consists of three components. First, in regions of young ocean crust (<67.7 Ma) the model estimate uses a half‐space conduction model based on the age of the oceanic crust, since it is well known that raw data measurements are frequently influenced by significant hydrothermal circulation. Second, in other regions of data coverage the estimate is based on data measurements. At the map resolution, these two categories (young ocean, data covered) cover 65% of Earth's surface. Third, for all other regions the estimate is based on the assumption that there is a correlation between heat flow and geology. This assumption is assessed and the correlation is found to provide a minor improvement over assuming that heat flow would be represented by the global average. The map is made available digitally.