Welcome!

     This blog is an exploration of what forests mean to the lives we want to be living--what threats forests face, what changes they are undergoing, and what the outcome of those changes seems likely to be.  My hope is that it will be a place where news about forests in this region, your ideas and articles on forest topics, and resources for learning about trees and forests in this area can all come together in one place. 

     Among other things, the blog contains several presentations I've developed on tree identification and on the history of naturalists in America; selections from an unfinished book on forests; and various notes on trees and forests.  They're all listed on the right hand side of the blog, under "Pages," and can be accessed simply by clicking on the title of the topic you're interested in.  Photos in the materials are my own unless otherwise indicated.

      Also on the right are links to various tree-and- forest-related websites you might want to make use of.

      Your thoughts are not only welcome but strongly encouraged!  You can either post in the comment section or e-mail me directly at taorivertony@gmail.com.

Tony Russell 

Secluded Farm; October 31, 2011

Forests as Biotic Wind Pumps

An intriguing theroy has been kicked around in the scientific world for more than a decade.  It’s particularly timely right now as the world watches videos of Australia aflame.

Back in 2006 and 2007, two Russian scientists named Anastassia Makarieva and Victor Gorshkov proposed that forests have a central role in driving weather and climate for the entire planet.  The theory, while controversial, explains phenomena that otherwise remain a mystery, such as how continental interiors like the Amazon and Congo can be as moist as coastal regions, and why Australia went from being a heavily forested continent to being heavily desert.

They theorize that vast forests generate winds that pump moisture across continents and around the globe.  Here’s how:  Gas occupies less space as it converts from a gas to a liquid.  This is true when water vapor condenses to form droplets and clouds.  Because the moisture takes up less space than the gas it formed from, local air pressure drops.  

The next key is that evaporation is greater over forests than over oceans, so coastal forests have lower air pressure than the nearby sea.  Thus they draw in moist air from the ocean, and the inrush of air generates winds that carry moisture toward the interior. As this process repeats itself in successive stages, moisture is cycled towards the continent's heart.

The total volume of water involved in this process would be almost unimaginable. The researchers suggest that, at least at the time they were writing, rainforests were sending more water into the atmosphere than evaporated from the surface of the world’s oceans. The Amazon rainforest, they said, was releasing 5.28 trillion gallons of moisture every day via evapotranspiration.

The implications of this theory are enormous.  If it proves valid, it will transform our vision of forests and climate change, since even relatively minor deforestation could cause the heart of a continent to dry out.

Smoke from Australia's bushfires, as photographed by the Japan Meteorological Agency's
Himawari 8 satellite, January 4, 2020

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"Clearing Forests May Transform Local—and Global—Climate" by Judith D. Schwartz in Scientific American, March 4, 2013.  Available online at https://www.scientificamerican.com/article/clearing-forests-may-transform-local-and-global-climate/

"The Biotic Pump: Condensation, atmospheric dynamics and climate" by Anastassia Makarieva and Victor Gorshkov in the International Journal of Water, vol. 5, no. 4, pp. 365–385 (January 2010); doi:10.1504/IJW.2010.038729.  Open access. Full text available in PDF format at https://www.researchgate.net/publication/228528788_The_Biotic_Pump_Condensation_atmospheric_dynamics_and_climate

"Biotic pump of atmospheric moisture as driver of the hydrological cycle on land" by Anastassia Makarieva and Victor Gorshkov in Hydrology and  Earth System Sciences, vol. 11, issue 2, pp. 1013–1033 (November 13, 2007); doi:10.5194/hess-11-1013-2007.  Open access.  Available online at https://www.hydrol-earth-syst-sci.net/11/1013/2007/  and downloadable in PDF format.