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blatherskiteI'm coming to the final pages of the book Fresh Water, a 1998 book by retired researcher and university professor E.C. Pielou. Her goal in this book is to explore the many and varied processes that govern how water flows through an ecosystem, and the complex reciprocal interactions between these processes and the plants and animals that inhabit the ecosystem. If you're an ecologist by training, like me, or simply fascinated in how the world works, you'll enjoy the book.
The author is not a brilliant writer, like Jared Diamond. There are many awkward phrasings, and in most of the rest of the text, the writing is serviceable rather than inspired. Pielou also loses a full letter grade for excessive reliance on unnecessary endnotes -- a practice I despise, particularly when the note text could have been easily and beneficially integrated with the text instead of relegated to the end, thereby requiring a second bookmark to make it more convenient to look up the notes. But she knows her stuff, and for the most part tells her story clearly and with insight.
Much of the book involves things I already knew, whether because I'd studied them formally in university or because I'd come across them over nearly three decades of editing journal manuscripts. But seeing everything together in one place, with all the links made explicit, more than justified the exercise of reading the book and refreshing my memories. Moreover, Pielou filled in a few unexpected holes in my education, and in one of those "d'oh!" moments, answered a question I'd completely misunderstood in the final exam of my course on boundary-layer climatology.
The question: Why does boiling a kettle not increase the relative humidity in your home? The answer the teacher was looking for is that what emerges from the kettle is mostly not water vapor (water in its gaseous form), but rather a suspension of fine droplets (water in its liquid form). The answer I gave him (which is, strictly speaking, more correct) is that (i) some of the emission really is water vapor, and (ii) once those droplets are emitted into the air, then so long as the air is not saturated, their greater surface area compared with the intact body of water still in the kettle will combine with their high temperature (near the point at which liquid water turns into a gas) to increase the humidity. A 32-year mystery is now resolved!
One large hole in my knowledge: Pielou raised my eyebrows to painful heights in her surprisingly negative review of the many problems created by the reservoirs behind dams. I already knew many of the problems (e.g., displacing native communities, disrupting ecosystems both above and below the dam, transformation of mercury into toxic and highly bioavailable methylmercury by microbes), but had largely considered these to be acceptable tradeoffs for the generation of "clean" hydroelectric power. But it turns out that hydroelectric power is rarely clean. Unless the reservoir is stripped of all organic matter before it is flooded, the plants drowned by the rising water remain at the bottom, where microbes decay them and generate large amounts of methane and carbon dioxide. For as long as the vegetation remains, and as long as new organic matter is being carried into the reservoir by the rivers that supply its water, the reservoir becomes a major source of greenhouse-effect gases. Enough so that some studies suggest reservoirs can emit as much of these gases as a coal-fired power plant that would be capable of generating a comparable amount of power. The result is probably cleaner (no sulfur oxides and heavy metals are emitted, unlike from the coal-fired plant), but still... yikes!
There are many reasons I love reading science. Having my eyes opened wide is one of the big ones.
The author is not a brilliant writer, like Jared Diamond. There are many awkward phrasings, and in most of the rest of the text, the writing is serviceable rather than inspired. Pielou also loses a full letter grade for excessive reliance on unnecessary endnotes -- a practice I despise, particularly when the note text could have been easily and beneficially integrated with the text instead of relegated to the end, thereby requiring a second bookmark to make it more convenient to look up the notes. But she knows her stuff, and for the most part tells her story clearly and with insight.
Much of the book involves things I already knew, whether because I'd studied them formally in university or because I'd come across them over nearly three decades of editing journal manuscripts. But seeing everything together in one place, with all the links made explicit, more than justified the exercise of reading the book and refreshing my memories. Moreover, Pielou filled in a few unexpected holes in my education, and in one of those "d'oh!" moments, answered a question I'd completely misunderstood in the final exam of my course on boundary-layer climatology.
The question: Why does boiling a kettle not increase the relative humidity in your home? The answer the teacher was looking for is that what emerges from the kettle is mostly not water vapor (water in its gaseous form), but rather a suspension of fine droplets (water in its liquid form). The answer I gave him (which is, strictly speaking, more correct) is that (i) some of the emission really is water vapor, and (ii) once those droplets are emitted into the air, then so long as the air is not saturated, their greater surface area compared with the intact body of water still in the kettle will combine with their high temperature (near the point at which liquid water turns into a gas) to increase the humidity. A 32-year mystery is now resolved!
One large hole in my knowledge: Pielou raised my eyebrows to painful heights in her surprisingly negative review of the many problems created by the reservoirs behind dams. I already knew many of the problems (e.g., displacing native communities, disrupting ecosystems both above and below the dam, transformation of mercury into toxic and highly bioavailable methylmercury by microbes), but had largely considered these to be acceptable tradeoffs for the generation of "clean" hydroelectric power. But it turns out that hydroelectric power is rarely clean. Unless the reservoir is stripped of all organic matter before it is flooded, the plants drowned by the rising water remain at the bottom, where microbes decay them and generate large amounts of methane and carbon dioxide. For as long as the vegetation remains, and as long as new organic matter is being carried into the reservoir by the rivers that supply its water, the reservoir becomes a major source of greenhouse-effect gases. Enough so that some studies suggest reservoirs can emit as much of these gases as a coal-fired power plant that would be capable of generating a comparable amount of power. The result is probably cleaner (no sulfur oxides and heavy metals are emitted, unlike from the coal-fired plant), but still... yikes!
There are many reasons I love reading science. Having my eyes opened wide is one of the big ones.