US EPA

1703418 

Journal Article 

Remote sensing measurements of greenhouse gas radiative fluxes 

Evans, WFJ; Puckrin, E 

2003 

Unk 

Proceedings of SPIE
ISSN: 0277-786X
EISSN: 1996-756X 

PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) 

5268 

220-228 

WOS:000189458300025 

A technique for the remote sensing of the forcing function of global warming (i.e., the increase in the surface radiative forcing) is described. Climate models predict that the emission of greenhouse gases into the atmosphere has altered the radiative energy balance at the earth's surface through increasing the greenhouse radiation from the atmosphere. With measurements at high spectral resolution, this increase can be unambiguously attributed to each of several anthropogenic gases. Calibrated spectra of the greenhouse radiation from the atmosphere have been measured at ground level from Peterborough, Ontario using an FTIR spectrometer with a resolution of 0.1 cm(-1). This long-wave radiation consists of the thermal emission from naturally occurring gases, such as CO2, H2O and O-3, as well as from many trace gases, such as CH4, CFC11, CFC12, CFC22 and HNO3. The forcing radiative fluxes from CFC11, CFC12, CC14, N2O, CH4, HNO3 and CO2 have been quantitatively measured. Measurements of the fluxes associated with each gas are presented. Models indicate that an energy flux imbalance of about 3 W/m(2) has been created by anthropogenic emissions of greenhouse gases of which we have measured over 1.0 W/m(2). Much of the remaining flux change is due to CO2 and CH4 increases which are difficult to measure without a long baseline data series. Overall, it has been demonstrated that the greenhouse radiation is measurable and it should be monitored on a worldwide basis over the long term since the predicted increase in this energy flux is the fundamental forcing of global warming. 

remote sensing; greenhouse gases; climate models; global warming; greenhouse effect; climate change