What is the potential of cropland albedo management in the fight against global warming? A case study based on the use of cover crops

Abstract

Land cover management in agricultural areas is a powerful tool that could play a role in the mitigation of climate change and the counterbalance of global warming. First, we attempted to quantify the radiative forcing that would increase the surface albedo of croplands in Europe following the inclusion of cover crops during the fallow period. This is possible since the albedo of bare soil in many areas of Europe is lower than the albedo of vegetation. By using satellite data, we demonstrated that the introduction of cover crops into the crop rotation during the fallow period would increase the albedo over 4.17% of Europe's surface. According to our study, the effect resulting from this increase in the albedo of the croplands would be equivalent to a mitigation of 3.16 MtCO 2 -eq.year −1 over a 100 year time horizon. This is equivalent to a mitigation potential per surface unit (m 2 ) of introduced cover crop over Europe of 15.91 gCO 2 -eq.year −1 .m −2 . This value, obtained at the European scale, is consistent with previous estimates. We show that this mitigation potential could be increased by 27% if the cover crop is maintained for a longer period than 3 months and reduced by 28% in the case of no irrigation. In the second part of this work, based on recent studies estimating the impact of cover crops on soil carbon sequestration and the use of fertilizer, we added the albedo effect to those estimates, and we argued that, by considering areas favourable to their introduction, cover crops in Europe could mitigate human-induced agricultural greenhouse gas emissions by up to 7% per year, using 2011 as a reference. The impact of the albedo change per year would be between 10% and 13% of this total impact. The countries showing the greatest mitigation potentials are

Estimating and tracking the remaining carbon budget for stringent climate targets

“…However, because of the diverse nature of Earth system feedback 42 , accounting for it through an adjustment in CO 2 emissions is not always straightforward. For example, if a feedback system results in the release of other greenhouse gases or affects the Earth system through changes in surface albedo, clouds or fire regimes, for example, its contribution needs to be translated into an equivalent CO 2 correction term (see refs 89,90 for example). Because most Earth system feedback is either sensitive to rising CO 2 or to variations in climate parameters, it is expected that these contributions are scenario-dependent, nonlinear, and in some cases realized over longer timescales only 40,41,85,[91][92][93][94][95][96][97][98] .…”

Developing a monthly radiative kernel for surface albedo change from satellite climatologies of Earth's shortwave radiation budget: CACK v1.0

“…Two simple empirical parameterizations of shortwave radiative transfer have been widely applied within the LULCC science community for estimating F from α s (Bozzi et al, 2015;Caiazzo et al, 2014;Carrer et al, 2018;Cherubini et al, 2012;Muñoz et al, 2010). While these parameterizations are also based on a single-layer atmosphere model of shortwave radiative transfer, at the core of these parameterizations is the fundamental assumption that radiative transfer is wholly independent of (or unaffected by) α s .…”

“…Within the LULCC science community, two methods have primarily met the need for efficient F calculations from α s : simplified parameterizations of atmospheric transfer of shortwave radiation (Bozzi et al, 2015;Bright and Kvalevåg, 2013;Caiazzo et al, 2014;Carrer et al, 2018;Cherubini et al, 2012;Muñoz et al, 2010) and radiative kernels (Ghimire et al, 2014;O'Halloran et al, 2012;Vanderhoof et al, 2013) derived from sophisticated radiative transfer schemes embedded in GCMs (Block and Mauritsen, 2014;Pendergrass et al, 2018;Shell et al, 2008;Soden et al, 2008). Simplified parameterizations of the LULCC science community have not been evaluated comprehensively in space and time.…”

Comparison of surface energy budgets and feedbacks to microclimate among different vegetation landscape on the Mongolian Plateau

“…Like in Arctic by a tundra-to-shrubland or a tundra-to-forest transition (Eugster et al, 2000;Souther et al, 2014); the South American Chaco (Houspanossian et al, 2017), in the tropical rain forests, and the Swiss Alps mountains in Europe (Rangwala and Miller, 2012), land cover change must be change the absorption active of sunlight. Especially for the human-induced land use changes, such as in forest-cropland and grassland conversion (Carrer et al, 2018;Zhao et al, 2017). Additionally, our result all confirmed that the significant negative correlation between them, such as the slope was 0.012 (p = 0.008) for MDW, was -0.013 (p = 0.047) for DRT and was -0.010 (p = 0.031) for SHB, was -0.006, (p=0.046) for TPL (Fig.…”