X-post. Very interesting! ---------- Forwarded message --------- From: Thomas Goreau <[email protected]> Date: Fri, 7 Sep 2018, 11:49 Subject: [CDR] Can solar and wind energy increase rainfall and vegetation? To: Carbon Dioxide Removal <[email protected]>, Soil Age <[email protected]>
A new paper suggests that large scale wind and solar energy farms in the Sahara could increase rainfall and vegetation, with most of the effect coming from vegetation feedbacks on climate: Climate model shows large-scale wind and solar farms in the Sahara increase rain and vegetation *Science 07 Sep 2018: Vol. 361, Issue 6406, pp. 1019-1022, DOI: 10.1126/science.aar5629* *Yan Li, Eugenia Kalnay, Safa Motesharrei, Jorge Rivas, Fred Kucharski, Daniel Kirk-Davidoff, Eviatar Bach, Ning Zeng* *Wind and solar farms offer a major pathway to clean, renewable energies. However, these farms would significantly change land surface properties, and, if sufficiently large, the farms may lead to unintended climate consequences. In this study, we used a climate model with dynamic vegetation to show that large-scale installations of wind and solar farms covering the Sahara lead to a local temperature increase and more than a twofold precipitation increase, especially in the Sahel, through increased surface friction and reduced albedo. The resulting increase in vegetation further enhances precipitation, creating a positive albedo–precipitation– vegetation feedback that contributes ~80% of the precipitation increase for wind farms. This local enhancement is scale dependent and is particular to the Sahara, with small impacts in other deserts.* *and a popular version:* *https://www.bbc.com/news/science-environment-45435593* <https://www.bbc.com/news/science-environment-45435593> *The results are easy to understand, but not clearly explained. Windmills and solar panels both have the same physical effects as vegetation: they increase surface roughness and the absorption of solar energy, leading to more energy transfer between surface and atmosphere, increasing surface temperature, and causing vertical convection that increases rain. That is to say, these renewable energy technologies have climatic benefits precisely because they unwittingly mimic the natural physical interactions of vegetation and climate (except for carbon storage!). Moreover they show that the bulk of the increased rainfall effect is due to increased vegetation feedbacks on climate from plant evapotranspiration effects, which they describe as “a previously overlooked vegetation feedback”. * *This is very telling, because it says previous models seem to have ignored the most important natural feedbacks by failing to model the vegetation mechanisms that help regulate climate change!* *Thomas J. F. Goreau, PhDPresident, Global Coral Reef AlliancePresident, Biorock Technology Inc.Coordinator, Soil Carbon AllianceCoordinator, United Nations Commission on Sustainable Development Small Island Developing States Partnership in New Sustainable Technologies37 Pleasant Street, Cambridge, MA [email protected] <[email protected]>www.globalcoral.org <http://www.globalcoral.org>Skype: tomgoreauTel: (1) 617-864-4226Books:Geotherapy: Innovative Methods of Soil Fertility Restoration, Carbon Sequestration, and Reversing CO2 Increasehttp://www.crcpress.com/product/isbn/9781466595392 <http://www.crcpress.com/product/isbn/9781466595392>Innovative Methods of Marine Ecosystem Restorationhttp://www.crcpress.com/product/isbn/9781466557734 <http://www.crcpress.com/product/isbn/9781466557734>* -- You received this message because you are subscribed to the Google Groups "Carbon Dioxide Removal" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/CarbonDioxideRemoval. To view this discussion on the web visit https://groups.google.com/d/msgid/CarbonDioxideRemoval/194BE15E-2492-4C26-8290-F34B648029DC%40globalcoral.org <https://groups.google.com/d/msgid/CarbonDioxideRemoval/194BE15E-2492-4C26-8290-F34B648029DC%40globalcoral.org?utm_medium=email&utm_source=footer> . For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
