Anthropogenic heat flux
(Data available here)

Nearly all energy used for human economy is, at some point, dissipated thermally within Earth's atmosphere or land.  This is a consequence of the second law of thermodynamics - the tendency of energy towards higher entropy (more disordered) forms.  Because the energy we derive from non-renewable sources (coal, petroleum, natural gas, and nuclear) would not otherwise have been introduced to the Earth System as heat (on relevant timescales), it can be considered a climate forcing term.  Globally, in 2005, this anthropogenic heat flux (AHF) was +0.028 W/m2, or only about 1% of the energy flux being added to Earth because of anthropogenic greenhouse gases.  The spatial distribution of AHF, derived from national energy-use data and population density, is shown to the right.  Although small globally, current AHF averaged over the continental United States and western Europe is, respectively, +0.39 and +0.68 W/m2, or up to 40% of the local forcing from carbon dioxide.  A projection of 2040 AHF is shown in the bottom panel.

AHF data, at multiple spatial resolutions, is available
here, and described in:

Flanner, M. G. (2009) Integrating anthropogenic heat flux with global climate models, Geophys. Res. Lett.,
36, L02801, doi:10.1029/2008GL036465.
(If you do not have AGU library access, use 23615034 for both login ID and password to access article)

Some other relevant papers (among many) include:

Chaisson, E. J. (2008), Long-term global heating from energy use, EOS Transactions, 89(28), 195, 253-254.

Crutzen, P. J. (2004), New directions: The growing urban heat and pollution ”island” effect - impact on chemistry and climate, Atmos. Environ., 38, 3539–3540.

Makar, P. A., S. Gravel, V. Chirkov, K. B. Strawbridge, F. Froude, J. Arnold, and J. Brook (2006), Heat flux, urban properties, and regional weather, Atmos. Environ., 40, 2750–2766.

Oleson, K. W., G. B. Bonan, J. Feddema, M. Vertenstein, and C. S. B. Grimmond (2008), An urban parameterization for a global climate model. Part I: Formulation and evaluation of two cities, J. Appl. Meteor. and Climatology, 47, 1038–1060.

Oleson, K. W., G. B. Bonan, J. Feddema, and M. Vertenstein (2008), An urban parameterization for a global climate model. Part II: Sensitivity to input parameters and the simulated urban heat island in offline simulations, J. Appl. Meteor. and Climatology, 47, 1061–1076.

Sailor, D. J., and L. Lu (2004), A top-down methodology for developing diurnal and seasonal anthropogenic heating profiles for urban areas, Atmos. Environ., 38, 2737–2748.

Washington, W. M. (1972), Numerical climatic-change experiments: The effect of man’s production of thermal energy, J. Appl. Meteor., 11, 768.


anthropogenic heat flux