Authors: Colin Tudge
14
The Future with Trees
O if we but knew what we do
When we delve or hew—
Hack and rack the growing green!
G
ERARD
M
ANLEY
H
OPKINS
,
“B
INSEY
P
OPLARS
,” 1879
H
UMANITY IS IN A MESS.
The statistics are simple and stark: a billion chronically undernourished, a billion in slums (and growing), more than a billion who live on less than two dollars a day. Even worse, because potentially more final, is the collapse of the earth itself, the place where we live. Soil, air, sea, lakes, aquifers, and rivers: all are under stress. Above all, potentially the coup de grâce, lies the reality of climate change. Global warming does not merely imply amelioration: Mediterranean beaches in hitherto chilly northern latitudes, vineyards in Scotland. It will bring a century and more of extremes, and of extreme uncertainty: flooding of reefs, mangrove swamps, and fertile coastal strips, of lowland countries and states from Bangladesh to Florida, and of cities from London to New York; stronger hurricanes, more often; the world’s great wheat and corn fields, our “breadbaskets,” potentially reduced to dust bowls; absolute loss of ancient habitats, including the beautiful frozen lands of the polar bear, the northern forests of spruce and aspens, and—most destructively of all—tropical rain forests. The first signs are with us. I have two grandchildren, and I fear for them.
Worst of all, though, is that the standard solutions to all our problems, bruited from on high by the world’s most powerful governments, are in truth their prime cause. “Progress” is the buzzword. If this meant improvement of human well-being and security, it would a fine concept, but in practice it does not. It has come to mean “Westernization”—that all the world should be more like us: more industrialized, which means more global warming; and more urbanized, which means less care for the countryside and even bigger slums. By 2050, by current projections, there will be as many people in cities (six billion) as now live on the whole earth. The cities cannot cope. Demonstrably, they are losing the race. At the same time, the world’s politics have become more abstract—geared not to physical realities but to the abstraction of money. Governments measure their success in GDP: total wealth created. Good endeavors can create wealth, of course, like building schools and planting forests. But bad things create wealth at least as easily—like felling forests and selling them off, or simply making war. The cash thus conjured up is all grist to the GDP and so, on paper, contributes to the great desideratum of “economic growth.” Agrarian economies that have ticked along for thousands of years in perfect harmony with their surroundings are said to be “stagnant” and “ripe for development.” “Development,” in turn, is equated with increase in cash. The fight against hunger, disease, oppression, and injustice has been reduced (dumbed down, one might say) to “the war on poverty.”
Yet very simple arithmetic shows that the Western goal of urbanized industrialized life and the promise of limitless wealth for everyone
cannot
be realized. Raising everyone in the world to the material standards of the average lower-middle-class, middle-income American would require the resources of at least three earths. Furthermore, the means by which this dream is being imposed on the world (in the name of “freedom,” “democracy,” and “justice,” as well as “progress”) seem expressly designed to undermine the well-being of most of humanity. For most people in the world live and work in the countryside, at rural crafts of which the chief is farming. Industrialization simply puts them out of work. If India farmed the way the British and the Americans do, half a billion people would be unemployed—more than the total population of the newly expanded European Union and close to twice the population of the present United States. No other industry can employ so many people as farming can, and still does, and no other industry could conceivably be so sustained. Most of Africa is even more emphatically rural than India and has even fewer realistic options. Yet Westernization—urbanization, industrialization, and a monetarized economy geared to GDP—is promoted by the world’s most powerful governments as the universal algorithm for all of Africa, Asia, and South America: the formula that, once applied, will solve all our problems. Even worse, the formula is applied with all possible haste, for the world’s new economy is driven by the perceived need for “competition.” But untempered competition is a crude concept indeed, as any worthwhile moral philosopher would attest, and any truly modern biologist could ratify.
The world needs a sea change. It isn’t just a question of changing our leaders’ minds, for that is too exhausting and we don’t have enough time. It isn’t a question of changing our leaders, for we are liable simply to land ourselves with more of the same. The world as a whole needs a different
kind
of governance, different kinds of people in charge. To ensure this, we (all of us, for it’s no use relying on the current leaders, who are doing well under the present system) must find new ways of ensuring that new kinds of people are elected and given real power: people who respond to the real, physical needs of the world, and to the needs of humanity at large. Present-day leaders—politicians and captains of industry—are wont to suggest that any radical initiative that takes account of the realities of soil, water, and climate is “unrealistic,” commonly because such initiatives may inhibit the plans of bullish industries and their governments, and hence inhibit “growth.” But the word “realistic” has been corrupted. It ought to apply to the realities that are inescapable—of physics, of biology—made manifest in the declining earth, and the creatures that live on it. It should apply to the realities of people’s lives—whether they have enough to eat, and water, and shelter; whether they have control over their own lives, and worthwhile jobs, and can live in dignity. The “reality” of which our current leaders speak is the reality of cash. But cash is not the reality. Cash is the abstraction.
A sea change, to mix the metaphors, may seem pie-in-the-sky. In truth, however, and encouragingly, most of the big and necessary ideas are already in place, or already being worked upon. Excellent ecological studies are under way. Truly appropriate technologies, designed expressly to be sustainable—both low-tech and high-tech—are developing apace, and many (including many of the simplest) are quite wonderful. And, which is at least as necessary, many groups worldwide are working on new economic models that, though basically capitalist, are geared directly to human well-being, rather than to the gross abstraction of accumulating cash. Certainly, there can be no surefire formulas. We simply cannot tell, until we try, whether our ecological projections and economic plans will work out the way we want them to. But if we keep our eyes on the right targets—human well-being in a diverse world; humanity able to live well, effectively forever—then we are in with a chance. If we proceed with reasonable caution, we can correct mistakes as we go. If we simply apply the present-day algorithms—high tech applied willy-nilly wherever it will make the most money the most quickly—then, surely, we and the world as a whole have had our chips.
Most important, the future endeavors of humanity must be geared to biological realities. The world’s economies (and the efforts of scientists and technologists) must serve those realities. Most obviously—once we start to think seriously about the fate of cities, and environmental stress in general, and human employment and dignity—we see that for the foreseeable future, and probably forever, the economies and physical structure of the world must be primarily agrarian. In the current, crude, unexamined dogma, “development” and “progress” mean urbanization. The prime requirement, in absolute contrast, is to make agrarian living agreeable. It can be. It’s just that at present, all the world’s most powerful forces are against it.
Trees are right at the heart of all the necessary debates: ecological, social, economic, political, moral, religious. It isn’t the case that trees are always a good thing. The wrong tree in the wrong place can do immense damage: eucalypts can turn areas that are merely dry virtually into desert; willows may encroach on wetlands and change their character—turning habitats for ducks and frogs into woodland; over-lusty garden trees may undermine houses; mountain ash trees near arable fields may provide wintering grounds for aphids; flowering exotics in austere native landscapes are aesthetically vulgar and often useless to native wildlife; and so on. It isn’t true that everywhere in the world needs more trees. In some places, there could be too many—lowering water tables that are already too low. The wrong trees in the wrong places can poison rivers, undermine buildings, and even cause soil erosion. Yet beyond any doubt, most landscapes and the world in general would benefit from many, many more trees than there are now, and the wholesale squandering of present-day forest seems like an act of suicide.
But it is also true—marvelously and encouragingly so—that societies can build their entire economies around trees: economies that are much better for people at large, and infinitely more sustainable, than anything we have at present. Trees could indeed stand at the heart of all the world’s economics and politics, just as they are at the center of all terrestrial ecology. The more I have become involved with trees in writing this book, the more I have realized that this is so. In the future of humanity, and of all the world in all its aspects, trees are key players.
THE BIGGEST CHALLENGE OF ALL: CLIMATE
The world’s climate has fluctuated spectacularly these past few billion years, often to fantastical extremes. At times the whole world has been tropical, with palm trees in Canada fringing the Arctic Ocean. At other times (long before the recent wave of ice ages) the entire surface may have frozen over. Beneath the streets of London—obligingly revealed by civil engineers during the past few hundred years—are fossils of crocodilians and of nipa palms, denizens of tropical rivers; but also of woolly mammoths, creatures of the tundra. Those who suppose, as some of the world’s leaders have chosen to do these past few decades, that the world is more or less bound to be the way it is now should look at the evidence all around of past deviations, or at least take notice of those who have.
All kinds of evidence show that the fluctuations in temperature, from global tropical to global freezing and back again, are correlated with the concentration of carbon dioxide in the atmosphere. Some of the most convincing evidence comes from ancient ice in Greenland and Antarctica, which traps atmospheric gas from earliest times that can then be directly analyzed. When the concentration of carbon dioxide was high, the fossils show, the world was warm. When it was low, the world was obviously cool.
The physics is simple. The earth is constantly warmed by sunlight, and constantly radiates the warmth away again. The solar energy coming in contains light of all wavelengths. The radiant heat that the earth gives out is all in the infrared spectrum. Carbon dioxide absorbs infrared. So atmospheric carbon dioxide filters out only a fraction of the solar energy coming in—a proportion of the infrared; but it traps a great deal of the energy going out, since most of what’s going out is infrared. So more energy is kept in than is kept out, and the net effect is to warm the atmosphere. The glass in a greenhouse operates in the same way, so this is called the “greenhouse effect” and carbon dioxide is called a “greenhouse gas.” Some other gases also have a greenhouse effect, including nitrous oxide, methane, and water vapor. But carbon dioxide is the main variable.
It may seem odd that carbon dioxide can have such an effect. After all, its concentration in the atmosphere is low. The present concentration of carbon dioxide in the atmosphere is only around 370 parts per million. Yet it has been calculated that if the atmosphere contained no carbon dioxide at all, the average surface temperature would fall to -18°C (0°F). At the time of the ice ages, atmospheric carbon dioxide was down to 190 to 200 parts per million; and it was indeed very cold. When plants first colonized land 400 million years ago, atmospheric carbon dioxide stood at around 7,000 parts per million—and the world was extremely warm. At the time when cyanobacteria first evolved photosynthesis, more than two billion years ago, the atmosphere contained no oxygen at all. Carbon dioxide was the chief gas of the atmosphere, apart from nitrogen. The world must then have been ridiculously hot. For creatures like us (or modern trees) the heat alone would have been lethal (let alone the noxiousness).
Modern meteorological records, and the notebooks of gardeners and naturalists, show that the world has been getting warmer during the past 150 years or so. The Intergovernmental Panel on Climate Change (IPCC) reported in 2001 that the average temperature of the whole world increased by 0.6°C (1°F) between 1900 and 2000. Such a rise may not seem great, but ostensibly small changes averaged over the whole world can imply huge changes locally and regionally—enough to have profound effects on environments and people. The trend seems inexorably upward: 1998 was the warmest year since reliable records began; and the 1990s was the warmest decade.
Changes in temperature cause changes in rainfall. Precipitation rises overall (since more water evaporates from the surface of the oceans), but the distribution is uneven; so some places become much wetter, others much drier. The IPCC noted an overall increase in precipitation (rain and/or snow) of 0.5 to 1 percent
per decade
through the twentieth century: up to 10 percent over the century. The increase was highest in the mid- and high latitudes of northern continents. In the tropics (10° north to 10° south) the increase was only 0.2 to 0.3 percent per decade, and in the northern subtropics (10° north to 30° north) rainfall actually
lessened,
by around 0.3 percent per decade. The subtropics are hugely important to humanity for our agricultural crops, our forests, and as places where people live. Drought in that latitudinal band is seriously bad news. In the Southern Hemisphere, which lacks a vast continental landmass and has vast oceans instead, there were no comparable changes—or at least the changes were not so regular.