File hfmap.asc contains global maps of the heat flow and its standard
deviation predicted using the seismic model based extrapolation of the
global dataset of heat flow measurements. 

Format: lon  lat  HF (mW/m**2)  sigmaHF(mW/m**2)

The extrapolation method is described by Shapiro and Ritzwoller (2004):
http://ciei.colorado.edu/~nshapiro/PUBS/Shapiro_Ritzwoller_epsl2004.pdf


Abstract:

We present a method that uses a global seismic model of the crust and
upper mantle to guide the smoothing and interpolation of heat flow 
measurements where they exist and the extrapolation of existing measurements to 
regions where such measurements are rare or absent. 
For any chosen spatial point on the globe the procedure generates a heat flow value 
as a weighted average over all regions where heat flow data are
available that are structurally similar to the target point.
The weights in the average are based on a ``structural similarity
functional'' which we introduce to quantify the structural analogy between 
different regions. 
We apply this procedure world-wide using the global heat flow data base 
of Pollack et al. (1993)
guided by an update of the 3-D shear velocity model of 
the crust and uppermost mantle of Shapiro and Ritzwoller (2002).
Particular attention is drawn to surface heat flow maps of Antarctica, because 
these maps are needed to understand the dynamics of Antarctic ice sheets. 
It is noteworthy that heat flow in West Antarctica may be
nearly three times higher than in East Antarctica. This high heat flow may
contribute to the instability of the West Antarctic Ice Sheet.