The World in 2050: Four Forces Shaping Civilization's Northern Future (17 page)

Imagining 2050

The trends I’ve described—rising water demand; oversubscribed and/or polluted water sources; reduced time-delays and free storage from snow and ice; sharper floods and droughts that are also harder to predict and insure against; the competitive marriage of water to energy; and booming port cities on increasingly risky coasts—all stem from our four global forces of demographics, natural resource demand, globalization, and climate change.

Whether for-profit multinational corporations offer the best solution for tackling water quality problems in impoverished countries remains an open question that is heatedly debated. However, global trade flows of “virtual water” embedded in food, energy, and other goods are already smoothing out some stark water inequities around the world. Compared with other irritants, international water disputes have seldom led to war. Continued economic integration could foment even better water management across borders—especially when nudged along by free hydrologic data measured from space and posted openly on the Internet. Finally, the not-so-far-fetched possibility that new international trade flows in water—not just virtual but actual, physical water—could emerge as a partial solution for some water-stressed places that will be explored further in Chapter 9.

Looking ahead to the next forty years, it’s not hard to see where the big pressure points lie. Joseph Alcamo directs a research institute at the University of Kassel dedicated to exploring different possible futures for humanity’s water supply. To do this they built WaterGAP,
²⁶⁵
a sophisticated computer model incorporating not only climate change and population projections but also other factors like income, electricity production, water-use efficiency, and others. WaterGAP is thus a powerful tool for simulating a range of possible outcomes depending on the choices we make.

A typical, “middle-of-the road” WaterGAP scenario is shown here for 2050.
²⁶⁶
Regardless of how the WaterGAP model parameters are twiddled, the big picture is clear: The areas where human populations will be most water-stressed are the same areas where they are water-stressed now, but worse. From this model and others, we see that by midcentury the Mediterranean, southwestern North America, north and south Africa, the Middle East, central Asia and India, northern China, Australia, Chile, and eastern Brazil will be facing even tougher water-supply challenges than they do today. One model even projects the eventual disappearance of the Jordan River and the Fertile Crescent
²⁶⁷
—the slow, convulsing death of agriculture in the very cradle of its birth.

Computer models like these aren’t built and run in a vacuum. They are built and tuned using whatever real-world data scientists can get their hands on. Take, for example, the western United States. In Kansas, falling water tables from groundwater mining is already drying up the streams that refill four federal reservoirs; another in Oklahoma is now bone-dry. These past observed trends, together with reasonable expectations of climate change, suggest that over half of the region’s surface water supply will be gone by 2050.
²⁶⁸
Kevin Mulligan’s projection of the remaining life of the southern Ogallala Aquifer requires no climate models at all—it simply subtracts how much water we are currently pumping from what’s left in the ground, then counts down the remaining years until the water is gone.

In the United States, the gravest threat of all is to the Colorado River system, the aorta of water and hydropower for twenty-seven million users in seven states and Mexico. It supplies the cities of Los Angeles, Las Vegas, Tucson, and Phoenix. It irrigates over three million acres of highly productive farmland. Global climate models almost unanimously project that human-induced climate change will reduce Colorado River flows by 10%-30%
²⁶⁹
and already, its water is heavily oversubscribed.

More water is legally promised to the Colorado’s various shareholders than actually flows in the river.
²⁷⁰
Its left and right ventricles are Lake Mead and Lake Powell, two enormous reservoirs created by the Hoover and Glen Canyon dams, respectively. They haven’t been full since 1999. A bitter combination of high demand, high evaporation, and falling river flows has thrown the Colorado River system into a massive net deficit of nearly one million acre-feet per year, enough water for eight million people. By 2005, Lake Powell was two-thirds empty and almost to “dead pool” (the elevation of its lowest outlet, below which no water can be released by the dam and it ceases to function).
²⁷¹
This desiccation stranded marinas and boat docks on dry land and left a white bathtub ring some ten stories high on Lake Powell’s newly exposed canyon walls. “It was as though in four years . . . Lake Powell had simply vanished,” wrote James Lawrence Powell of his namesake in
Dead Pool
.

I’m glad humanity has a decent track record with things like settling water disputes with courts rather than missiles, and exporting food from the places that have water to the places that don’t: If any of these model forecasts are correct, we’re going to need it. Humans currently withdraw about 3.8 trillion cubic meters of water annually, and are projected to require more than six trillion in the next fifty years. To serve India’s expected 2050 population of 1.6 billion, even with improved water efficiency, will require a near-tripling of its water supply. Farmers, energy utilities, and municipalities are all in competition for water. Put it all together and the numbers don’t add up. Something will have to give.

The survival of California’s thirsty dry cities—like Los Angeles and San Diego—seems all but guaranteed. Their populations and economies are growing briskly. Despite annual sales of over USD $30 billion, California agriculture still contributes less than 3% to the state’s economy—and cities use far less water than irrigated farms. Even with climate changes and a projected 2050 population of about 20 million, there will still be ample water for Angelenos and San Diegans to drink and shower and cook. Ample water for California farmers, however, is far less assured.

Forced to choose, cities will trump agriculture. Farmers will either lose or sell their historic water rights. Croplands will return to desert. The first signs of an urban takeover have already begun: After years of lawsuits, farmers of California’s Imperial Valley were forced to sell two hundred thousand acre-feet of their yearly Colorado River water allocation to San Diego in 2003. That fallowed twenty thousand acres of farmland. By early 2009 the Metropolitan Water District—supplier of twenty-six cities throughout Southern California—was trying to buy
seven hundred thousand
acre-feet more.
²⁷²

Cities versus farmers: the real Water Wars.

PART TWO

THE PULL

CHAPTER 5

Two Weddings and a Computer Model

M
y adoptive groomsman, whom I’d just met the night before, cracked open the church door and peeked anxiously out at the parking lot. It was a sorry mess of black asphalt, lingering slush, and streaming water. Some early guests were sitting in their cars, peering through their headlights for a dry way into the church. It was early afternoon but very dark. I’d expected dim—we were, after all, just three hundred miles shy of the Arctic Circle in the middle of winter—but not this. The expected reflective blanket of fluffy white snow was gone. My dress socks were wet and cold. We’d strategically timed our wedding day for the prettiest, whitest, most winter-wonderland month of the year. But instead, in the middle of February, some five hours north of Helsinki, a thousand miles northeast of London, and almost twenty degrees of latitude north of Toronto—there was only a steady downpour of rain.

More precisely it was our
first
wedding day, taking place across the Atlantic for my new European family and friends. Our
second
wedding day—for American families and friends—was a month later in the sunny desert resort of Palm Springs, California. Mid-March is peak tourist season in Palm Springs, with infallible blue skies and flawless temperatures hovering in the 70s. We had booked all outdoor venues for the day’s events. Our tremulous queries about tents and patio heaters—just in case of a weird-weather repeat—were politely but firmly dismissed. The weather here is
always
perfect in March, we were told. That’s why people pay twice as much to come then.

You know what happened next. A line of fat squalls sprayed cold rain onto our guests’ unprotected heads. By the time the lasagna came out, the temperature had plunged fifteen degrees. We did manage to scrounge up four patio heaters somehow, around which the jacketless masses could huddle. We were shocked and upset—again—by freaky weather. But just like our sub-Arctic celebration, the crowd’s good spirits soon prevailed. Both ceremonies went on as planned. Cakes were cut, dances were danced, and good times were had by all.

I shouldn’t have been so surprised. While there will always be some weird weather happening somewhere, my wedding experiences were consistent with everything we know about the statistics of climate change. I had described such phenomena many times (though as probabilities, not specific occurrences) to thousands of students in my lectures at UCLA. From my research and travels to the NORCs, plenty of people had told me about bizarre rains in the depths of winter. After a while I’d even become bored with it—one can only listen to so many bizarre-weather stories before it just isn’t new information anymore.

In the previous chapter, we explored how the statistical norms of flood and drought frequency are changing, and how they might become more intense in the future. Now it is time to discuss rising air temperatures in the North—even in the dead of winter and at very high latitudes. Indeed, this phenomenon is a central interest throughout the rest of this book.

Four facts about global climate change need to be made very clear.

The first is that any process of climate change—both natural and man-made—unfolds erratically over time. In fact, its behavior is not unlike that of the stock market.

As every investor knows, long-term trends in the stock market are overprinted with short-term fluctuations. We don’t normally assume that share prices will move smoothly up or smoothly down. Instead, and usually within days, we expect they will reverse, before reversing again, and so on. Wise investors accept this short-term volatility as being largely unpredictable, yet bank on the existence of an underlying long-term trend to guide their overarching portfolio strategy. They say that while short-term markets react to unpredictable things like profit-taking, news reports, and God-knows-what, a long-term trend is more fundamental. And indeed, they are right. Throughout modernity the long-term trend has been for stock values to rise. Its underlying driver is growth of the real economy, fueled by the steady rise of human population and prosperity.

The long-term trend for the Earth’s climate, for at least several centuries, is rising air temperatures in the troposphere (lower atmosphere). Its underlying driver is radiative forcing commanded by the steady rise of carbon dioxide and other greenhouse gases produced as by-products of human activity. Because carbon dioxide, in particular, can linger in the atmosphere for many centuries this buildup is, for all intents and purposes, permanent.
²⁷³
Over the long haul, the world’s global average temperature must go up. As shown in Chapter 1, the physics of this has been known since Svante Arrhenius’ work in the 1890s.

Beyond this broad, average trend, however, the warming process gets more complicated. Our planet is not simply a dry rock with a sunlamp shining on it. The additional heat trapped by greenhouse gases is absorbed, released, and moved around the planet by sloshing ocean currents and turbulent air circulation patterns. Living things breathe air in and out, and store or release carbon—a fundamental ingredient of CO
₂
and CH
₄
greenhouse gases—in their tissues. When the ground is bare, it absorbs sunlight, causing local heating. When snow-covered it reflects, causing local cooling. Volcanic eruptions punch aerosols into the stratosphere, shading and cooling the planet for a few years until they dissipate.
²⁷⁴
The energy output of the Sun waxes and wanes slightly. All of these little and not-so-little natural mechanisms and feedbacks are to climate change what profit-taking, insider trading, and short sellers are to the stock market. They muck up the underlying greenhouse forcing trend, overprinting it with shorter fluctuations that rise and fall, then rise again.
²⁷⁵
If not for this natural variability, we’d have caught on to the deeper greenhouse signal even sooner than we did.

Any competent financial planner will tell you that the road to secure retirement is paved with market drops. Any competent climate scientist will tell you that our road to a hotter planet will be paved with cold snaps, even record-breakers. But unfortunately, when it comes to communicating this to the general public, we scientists have done a poorer job of it than financial planners. Perhaps it’s not surprising, therefore, that so many people will glance outside at the bitter cold and scoff at global warming—even as they log on to E-Trade to buy up the latest stock market dip.

The second important fact about climate change is that its geography is neither always global nor always warming. To be sure, it is
mostly
global and
mostly
warming. But because of the many complex natural mechanisms and feedbacks that inject themselves into the process, the final climatic manifestations of greenhouse forcing vary greatly in spatial pattern. Climate change is not only erratic in time, like the stock market, but also in geography. A globally averaged temperature increase of one degree Celsius does not mean temperatures rise everywhere around the globe by one degree Celsius. That’s just the average. Some places will heat up a great deal, others won’t or might even cool. Summing them all together gets you to the +1°C global average. But that seemingly small number masks some stunning differences around the world.

Consider the map below. It is a projection of our future temperature changes by the middle of this century. Some places are warming hugely but other places hardly at all.
²⁷⁶
Why is this? Has some climate model gone haywire?

This map is not an oddball, but just one of a family of nine related maps released by the latest IPCC Assessment.
²⁷⁷
They all show irregular geographic patterns and appear together on the following page in a three-by-three grid. From left to right they plot out a three-stage timeline for our century, with average, smoothed-out temperature changes apparent by 2011-2030, by 2046-2065, and by 2080-2099. Like the single map on page 126, each one is actually produced from not one but many climate models—much like a stock index—thus capturing where the models robustly agree rather than the quirks of any particular climate model over another.

Each of the three rows corresponds to a different concentration of greenhouse gas in the atmosphere. That, in turn, rests on all sorts of things, from political leadership to energy technology to gross domestic product. Rather than try to predict which outcome will actually transpire, the IPCC instead calculates outcomes for numerous possible social paths (called SRES scenarios
²⁷⁸
), of which three are shown here. The first outcome (top row) may be described as a highly globalized world, with population stabilizing by midcentury and an aggressive transition to a modern information and service economy. This scenario (known to climate scientists as “B1”) is labeled “optimistic” on the figure.
²⁷⁹
The second outcome also assumes a stabilizing population and fast adoption of new energy technologies, but with a balance of fossil and nonfossil fuels. That future (called “A1B” by climate scientists) is labeled “moderate.” The third outcome assumes a very divided world with high population growth, slower economic development, and slow adoption of new energy technology. This future (called “A2”) is labeled “pessimistic.”

The third important fact about global climate change is revealed by comparing these three rows of maps. They show that, regardless of technology path, we are already locked in to some degree of warming; but by century’s end, the actions or inactions taken now to curb greenhouse gas emissions really will matter enormously. By 2080-2099 the “pessimistic” world is indeed a cauldron compared to the “optimistic” one, with temperatures rising 3.5°-5.0°C (9°F) across the conterminous United States, Europe, and China, rather than 2.0°-2.5°C (4.5°F). While these numbers may seem small, in fact there is a huge difference between the two outcomes. A 2.5°C rise in average annual temperature is actually huge, equivalent to the difference between a record cool and record warm year in New York City. So even in the “optimistic” world, what is today considered an extreme warm year in New York will become the norm; and the new extremes will be unlike anything New Yorkers have ever seen.

The “pessimistic” numbers are even more alarming. They approach the magnitude of average temperature contrast between the world of today and the world of twenty thousand years ago during the last ice age, when global temperatures averaged about 5°C (9°F) cooler. Many areas of North America and Europe were under ice, sea levels were more than 100 meters (330 feet) lower, and Japan was actually connected to the Asia mainland.
²⁸⁰

All of these maps are conservative in that they awaken no hidden “climate genies” that give climate scientists nightmares.
²⁸¹
Instead, they chart out the plain vanilla, predictable intensification of the greenhouse effect, covering a realistic range of options lying well within control of human choices.