Imperial College London
Portrait Picture

DrEdwardGryspeerdt

Faculty of Natural Sciences, The Grantham Institute for Climate Change

Royal Society University Research Fellow
 
 
 
//

Contact

 

+44 (0)20 7594 7900e.gryspeerdt Website

 
 
//

Location

 

708Huxley BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Gryspeerdt:2016:10.1002/2015JD023744,
author = {Gryspeerdt, E and Quaas, J and Bellouin, N},
doi = {10.1002/2015JD023744},
journal = {Journal of Geophysical Research: Atmospheres},
pages = {3566--3583},
title = {Constraining the aerosol influence on cloud fraction},
url = {http://dx.doi.org/10.1002/2015JD023744},
volume = {121},
year = {2016}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Aerosol-cloud interactions have the potential to modify many different cloud properties. There is significant uncertainty in the strength of these aerosol-cloud interactions in analyses of observational data, partly due to the difficulty in separating aerosol effects on clouds from correlations generated by local meteorology. The relationship between aerosol and cloud fraction (CF) is particularly important to determine, due to the strong correlation of CF to other cloud properties and its large impact on radiation. It has also been one of the hardest to quantify from satellites due to the strong meteorological covariations involved. This work presents a new method to analyze the relationship between aerosol optical depth (AOD) and CF. By including information about the cloud droplet number concentration (CDNC), the impact of the meteorological covariations is significantly reduced. This method shows that much of the AOD-CF correlation is explained by relationships other than that mediated by CDNC. By accounting for these, the strength of the global mean AOD-CF relationship is reduced by around 80%. This suggests that the majority of the AOD-CF relationship is due to meteorological covariations, especially in the shallow cumulus regime. Requiring CDNC to mediate the AOD-CF relationship implies an effective anthropogenic radiative forcing from an aerosol influence on liquid CF of −0.48 W m−2 (−0.1 to −0.64 W m−2), although some uncertainty remains due to possible biases in the CDNC retrievals in broken cloud scenes.
AU  - Gryspeerdt,E
AU  - Quaas,J
AU  - Bellouin,N
DO  - 10.1002/2015JD023744
EP  - 3583
PY  - 2016///
SN  - 2169-897X
SP  - 3566
TI  - Constraining the aerosol influence on cloud fraction
T2  - Journal of Geophysical Research: Atmospheres
UR  - http://dx.doi.org/10.1002/2015JD023744
UR  - http://hdl.handle.net/10044/1/41543
VL  - 121
ER  -
Download