by John Bradley
I recently read two excellent books that took me back to some climate science basics. Both contain good insights on how we are impacting the climate, biodiversity, and the earth’s ecosystems.
Tim Flannery’s 2005 classic The Weather Makers: How Man is Changing the Climate and What It Means for Life on Earth is a collection of 36 essays focused on the carbon cycle. Each is an intriguing and eye-opening illustration of the fundamental earth systems that regulate and change climate. Two chapters about the cold intrigued me most, one about an early ice age, 700 million years ago, and another about the arctic today. The second book, Hydrate the Earth: the Forgotten Role of Water in the Climate Crisis by Ananda Fitzsimmons (2021), explains the short water cycle and focuses on its role in restoring ecosystems.
As Flannery notes, the earth’s temperature is regulated by many things, amongst them are mix of atmospheric gasses, especially the ratio of oxygen (O2) to carbon dioxide (CO2), the amount of the sun’s energy captured by the earth’s atmosphere (including CO2 and water vapor), and what living organisms may be doing to the O2:CO2 ratio and ecosystems. In the 21st century, a main concern is the increase of CO2 and other greenhouse gasses accumulating in the atmosphere from burning fossil fuels, thus warming our climate.
An ice age millions of years ago occurred when more organic matter (carbon) was sequestered and less CO2 was in the atmosphere, so more heat escaped the earth and the temperature plummeted (pardon the oversimplification). With more oxygen and less CO2, it is a runaway process deepening the ice age. In this specific chapter, Flannery explains interesting aspects of how the ice ages sustained themselves. Much of it is driven by the Albedo effect, whiteness on the earth from snow and ice reflecting the sun’s energy out, thus keeping temperatures down.
During an ice age over 540 million years ago, microorganisms in the ocean evolved, building skeletons of carbonate, which utilized CO2 from their seawater environment, thus reducing CO2 levels in the atmosphere, and the world warmed up a bit. Over millions of years, life forms evolved, or more accurately coevolved with astounding interdependencies, and the atmosphere, ‘the great aerial ocean,’ regulated the planet’s temperature such that life could continue. This is a brilliant example of evolving life forms impacting climate.
The many factors regulating climate, weather and temperature evolved with variation around the globe. Interestingly, climate effects are accentuated at the poles. Warming is occurring faster in the arctic than closer to the equator. Unfortunately, warming at the poles creates a positive feedback loop. Warmer temperatures result in less snow cover, so less white surface reflecting heat out (the Albedo effect), so more warming, and more thawed permafrost releasing greenhouse gasses that trap heat in the atmosphere, resulting in warmer temperatures, etc. - a positive feedback loop. These are some of the dynamics of the carbon cycle that impact the world and underlie our present warming.
The Weather Makers is an instructive read. It covers the history of the sciences, science policy as well as chapters on other factors that operate to change climate. The last section includes several chapters on what is in store for the earth under several alternative scenarios. It also includes recommendations and practical steps to help divert the disaster.
The climate we experience reflects a vast complexity of natural and not-so-natural systems. Almost all branches of science contribute. Life on Earth has evolved with incredible complexity and interconnectedness. Issues around the carbon cycle (e.g. reducing greenhouse gas emissions) are well understood, widely publicized, and embedded in public policies. Less understood is the water cycle and its role in ecosystem degradation, protection and regeneration.
Both authors make note that even if greenhouse gas emissions (GHGs) stopped today, the full effects of all the GHGs presently in the atmosphere would not be fully felt until 2050. Both also find it disturbing that there is not more recognition of the importance of preserving and restoring the earth’s ecosystems, which modern economies have been destroying at an ever-increasing pace. These are the ecosystems that through the ages have sustained livability, the essential interdependencies for all species, that are essential for human survival. Climate science and policy increasingly recognizes that ending GHG emissions and preventing further warming will not be sufficient alone. The ecosystems that provided the enabling conditions for the evolution and sustainability of life on earth need to be regenerated. This is a central theme of Hydrate the Earth.
Recently, I was referred to an online resource, the Regenerative Water Alliance (RWA) to learn more about restoring our ecosystems. Regeneration is not just preservation and conservation, but how to restore degraded lands and soil and how to reverse desertification, a horrifying outcome anywhere. RWA’s posts led me to Hydrate the Earth: The Forgotten Role of Water in the Climate Crisis (2021). The author, Ananda Fitzsimmons, a Canadian ecologist, gives us a clear explanation of both the long water cycle and the short water cycle. This understanding is critical for regenerating much of our ecosystems, especially where desertification is slowly occurring.
The long water cycle refers to the process of water being carried in the atmosphere from the oceans and released over the lands. The short water cycle is the water on land being absorbed in the soil, taken in by vegetation, especially forests, and transpired up from plants’ deep roots and released through tree tops as water vapor into the atmosphere, where it helps form clouds, which release rain. This short water cycle is repeated many times as weather moves across a land mass and maintains healthy ecosystems and biodiversity. The short water cycle also helps cool the earth and replenish groundwater. This hydration of land masses depends on vegetation, especially forests, soil and water.
The short water cycle is disrupted in many ways: cleared vegetation, widespread deforestation, mono-cropping (including lawns), degraded soils, industrial agriculture, and extensive urban and industrial paving-over that prevents the water from continuing its journey through the natural short water cycles. The cumulative result is that on all continents vast areas of land are desertifying. Perhaps one of the most well-known examples is the Fertile Crescent, once the cradle of agriculture and a vast breadbasket, now mostly desert in the Middle East. In the present time, these disruptions also prevent rainwater from passing through the soil to resupply aquifers on which human civilization depends for drinking water and agriculture.
Hydrate the Earth is an enriching discussion of how the water cycle can be regenerated, soil and biodiversity restored, and ecosystems preserved and restored. Over half the book is optimistic and inspirational as Fitzsimmons reviews numerous examples on several continents.
Chapter Five, ‘Bringing Degraded Land Back to Life,’ tells three dramatic stories in Canada, Australia and Saudi Arabia, respectively. Another chapter addresses ecosystem preservation and restoration. And the author does not ignore urban areas with a chapter on Green Infrastructure and Earthworks. Hydrate the Earth is an optimistic work packed with usefully applied climate science.
Notes/References
The Weather Makers: How Man is Changing the Climate and What it means for Life on Earth,
Tim Flannery, 2005, Atlantic Monthly Press, NY.
https://en.wikipedia.org/wiki/The_Weather_Makers
Hydrate the Earth: the Forgotten Role of Water in the Climate Crisis by Ananda Fitzsimmons,
2021, Editions La Butineuse. https://www.editions-labutineuse.com
Ananda Fitzsimmons talks about her book in the July 2022 edition of the
Regenerative Water Alliance - https://regenerativewater.substack.com/p/regenerative-water-
alliance
America is Using Up Its Groundwater Like There’s No Tomorrow: Overuse is draining
and damaging aquifers nationwide. NYT 8/28/23 https://www.nytimes.com/interactive/2023/08/28/climate/groundwater-drying-climate-
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