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GLOBAL WARMING AND THE COASTSIDE

The lack of public discussion about the local effects of global warming is understandable: we’re not on the front lines of climate change, like those living in the Arctic or on a Pacific atoll. Still, the Coastside is going to experience plenty of climate change in the decades to come. This essay will examine the most predictable local effects of global warming, perhaps sparking some discussion how we might adapt to a warming Coastside, and mitigate the more negative consequences.

There are a number of things this essay will not attempt. Most importantly, it will not attempt to convince anyone that our planet is warming. Nor will it attempt to sort out how much of planetary warming is natural, and how much is human-caused (anthropogenic), or how fast the warming will proceed. It won’t speculate -- as the head of NASA did recently -- that the ideal temperature of the planet might be higher than it presently is, so maybe global warming will be a good thing after all. Further, there will be no mention of actions humankind might take to arrest or reverse global warming. Lastly, the more debatable local weather consequences of climate change, such as whether we will predictably receive more or less rain, will not be treated here.

THE INLANDERS ARE COMING

One of the basic facts of global warming is that land masses warm much more, and much more quickly, than the oceans. In our region, that means that inland California will heat up more dramatically than coastal California, which is protected by the Pacific’s ability to absorb and dissipate heat. The comparative desirability of our area will cause a marked future increase in visitors, especially those fleeing summer inland heat waves, which will become more frequent, longer and hotter as the planet warms.

This increased seasonal tourism will be encouraged by the breakup of our summer fog season. While some may believe that warmer temperatures will actually increase Coastside summer fog, experience along the California coast through the last few decades has shown that even a mildly warming climate tends to push the fog bank offshore, while evaporating the fog along the coastline. From the South Coast and Santa Barbara through Carmel/Monterey to our own Coastside farmers, it is a common anecdotal observation that there already are a lot fewer fog days than before. And as locals noticed this year, even the foggy days were warmer and more pleasant than the bone-chilling summers of decades past.

For most summer travelers, when choosing a destination, weather is a paramount consideration. And since people prefer their summers to be reliably warm and sunny, especially when beachgoing, the Coastside has so far avoided the incredible crowds that routinely blanket the warm and sunny parts of the California coast. But as our fog is broken up, we’re not going to be able to fly under the radar any more. Developments like the Devil’s Slide tunnel and Harbor Village will certainly attract visitors, but it is the inevitable increasing public awareness of the changing weather that will really open the floodgates. As the Coastside becomes more of a summer playground destination, congestion and traffic will multiply, while Princeton harbor will develop into a pleasure-boating mecca. Naturally all these happy visitors will wonder why they don’t just up and move here, and many probably will.

MICROCLIMATES AND GLOBAL WARMING

A small geographic area that has a climate and seasonal weather distinct from the areas surrounding it is said to have a microclimate. The Coastside, as all locals know, is composed of a number of microclimates, often sharply defined, so that the neighbors down the block or across the valley might live in a different weather world. A Coastside farmer will often plant patches differently across his acreage, depending on which microclimate they fall into.

Because of these microclimates, and the fact that our local weather stays within a fairly tight temperature range, the Coastside has flora and fauna that are narrowly adapted to their natural conditions. When those natural conditions change, as in a warming climate, the stresses on the plants and animals are immediate. Animals, especially human beings and insects, tend to adapt to changing circumstances more easily than plants. Of the plants, smaller species, especially those that spread and proliferate quickly, adapt better than larger more stationary species like trees and bushes. In general, for both plants and animals, non-native species often adapt better to change than native species.

Many stresses are in store for our local natural order. Coastside Monterey pines are already afflicted by pine pitch canker, a disease borne by beetles that are predicted to flourish with a warming climate. California cypresses, while considered resistant to the canker, will be predictably stressed by the lack of summer fog, a daily bathing they need to get through our long rainless season. By winter, these weakened, shallow-rooted, top-heavy cypresses will topple more easily in windstorms. Since storm winds are considered to be created by differences in temperatures (an even-temperatured planet therefore being essentially windless), and since ocean/land temperature differences are anticipated to increase, it is predictable that our windstorms will become more powerful and destructive.

Monterey pines and California cypresses, the two omnipresent large tree species on the Coastside, will present an increasing fire danger as they die from disease, drought or storm damage, especially where they are overplanted between houses. The canker-dessicated pine is particularly flammable once its branches become withered, and its trunk hollows. Snap a dead branch off a blighted tree in your neighborhood, add it to the next fire you burn at home -- then stand back in amazement.

Coastside agriculture and fisheries will both be affected by the local warming. Crops that were closely adapted to our growing conditions will become less successful, while other crops (like wine grapes) may become more locally viable. It is predictable that all crops will be susceptible to a new range of pests. As our ocean waters warm, cold water species will move away, while warm water species (like tuna) might flourish. All local marine species will face greater challenges on many fronts, whether from overharvesting, increased pollution, or a lessening of upwelling -- starving the upper and nearshore waters of nutrients.

...AND THE SEA WILL RISE UP

For a community strung out along the ocean, a crucial concern about global warming is how much our sea level will rise. A few numbers may provide some perspective. Beginning with a total doomsday scenario, if all the glaciers and polar caps were to melt, so that we had an iceless world, the sea level would rise something more than 200 feet. The U.N. Intergovernmental Panel on Climate Change (IPCC) offered a number of scenarios for sea level rise by the year 2100, ranging between 3 and 20 feet (Al Gore used the highest estimate in An Inconvenient Truth). For reference, San Francisco Bay has been measured to have risen about 8 inches over the last 40 years, or about an inch every five years.

In a recent edition of Scientific American (August 2007), some of the IPCC scientists acknowledged that their sea level estimates may have been too low, because they emphasized the expansion of the existing ocean waters (warmer water occupies more space than cooler water), not the additional water supplied by the rapid melting of major glaciers and polar caps. In any event, the rise in sea levels will sooner or later exceed even the highest IPCC estimates, because of what climatologists call “climate inertia,” meaning in our situation that the globe will warm (and seas rise) for approximately 1000 years regardless of whatever countermeasures we take. That is, the tipping point for long-term global warming has been passed.

If we take any of these estimates seriously, there are some obvious candidates for shoreline inundation on the Coastside over the next decades. Highway 1 at Surfer’s Beach (including some of Burnham Strip to the east), entire tracts of old Princeton, as well as the harbor breakwaters, will certainly be among the first trouble spots. On the bright side, many oceanfront estuaries and wetlands, such as Pillar Point and Pescadero marshes, will refill and expand. Also refilling -- from below -- will be some areas that used to be shoreline marshes, for example Linda Mar Center and Strawflower Village, two shopping malls sited where brackish estuaries had conveniently compacted and leveled the soil for eons. When you’re standing in the aisle at Linda Mar or Half Moon Bay Safeway, trying to decide what to have for dinner, you’re in the same spot a heron stood less than a century ago, trying to decide the same thing. The herons may someday soon stand there again.

Another predictable consequence of rising sea levels is that local oceanfront bluffs will retreat more quickly, because wave action will more often eat away at the base of the cliffs, especially during storm surges, whose damaging effects will be magnified by higher sea levels. Also, migrations of beach sands will increase, as the sandy areas are engulfed in the intertidal zone. Finally, rising sea levels may cause more saltwater intrusion of water wells at lower elevations, such as the airport wells, upon which Moss Beach and Montara currently rely for about half their freshwater supply.

WATER AND ENERGY USAGE RISE WTH THE THERMOMETER

The only time we usually have an energy crisis in California is when it’s hot. People not only use more electricity during heat waves, with air conditioning and room fans, they also use more water, whether watering the lawn and garden or showering and bathing more often. Of course people also get thirsty in hot weather, and some even drink tap water. Coastsiders in a warming climate will predictably use more water and more electricity per capita than we do now. There will however be greater potential for solar power, with the increased sunshine, as well as wind power, given the often windier conditions.

ARE WE THE VICTIMS OF GLOBAL WARMING?

Because global warming is a kind of slow-motion train wreck (we hope it’s slow), and because we are locked into this train, it’s natural to feel like global warming is a calamity that someone or something else is doing to us. But if the warming is in large part anthropogenic, as most climatologists have firmly concluded, we Coastsiders are living the sort of environmentally incorrect lifestyle that contributes to the problem.

First, we are Americans, burning through approximately six times the energy that the average non-American around the globe consumes. In the majority, we live an aggressively acquisitive, consumptive and disposable lifestyle. Americans are responsible for a government that has a dismal record of cooperation with the international community on global warming. If the rest of the world wanted to live as we do, it would take six planet Earths, and we’d probably still run out of energy.

Second, as Coastsiders we have chosen to live in an environmentally sensitive part of our country that, if not for the Ocean Shore Railway, would likely be as underpopulated and bucolic as the South Coast is today. Our exurban lifestyle requires us to travel long distances by car for almost all services, even schools and basic shopping. Most of the goods sold on the Coastside are likewise trucked long distances from over the hill.

Third, most of us compound our exurban hydrocarbon impacts by not making our living on the Coastside, instead commuting back-and-forth a few times a week the many miles to the City, Peninsula or Silicon Valley. Commuting is an environmentally incorrect discretionary lifestyle choice, because unless we work in the merchant marine, in almost all cases we could live very close to where we work. We simply choose not to. And it unfortunately doesn’t matter a great deal if we commute with an economical car: even if we were Fred Flintstone, pedaling the car with our feet, we’d still be contributing to the air pollution and energy wastage by helping to create a traffic line with all the other commuters every day during peak driving hours.

The hard truth is that we cannot be American exurban commuters and blame someone or something else for the negative consequences of global warming. As Coastsiders, having consciously chosen an environmentally incorrect lifestyle that is unsustainable and unavailable to the mass of humanity, we will occupy the caboose of this slow-motion train wreck called global warming, but we’re still stuck on the train.


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from the August 19, 2004 edition

Global warming's surprising fallout


As we go on pumping carbon dioxide into the air, we might borrow a line from financial planners. Past performance is no guide to future results.

The buildup of carbon dioxide (CO2) is forcing scientists to rethink their expectations - not only about the buildup of heat on Earth but also about the implications for the natural world far beyond warming.


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Take those powerful Alaskan earthquakes. We expect land to rise as the weight of glaciers melts away. Should we also adjust our assessment of earthquake risk?

Two geophysicists say "yes." Glaciers hold down earthquake action even in a seismically active region like Alaska, argue Jeanne Sauber with NASA's Goddard Space Flight Center in Greenbelt, Md., and Bruce Molnia with the US Geological Survey in Reston, Va. They use history and current data to make their case.

For example, earthquake action picked up in places where the ice masses retreated some 10,000 years ago, Dr. Sauber notes. Scandinavia had major quakes back then. Canada also had many moderate quakes as its glaciers melted.

Melting glaciers do not cause earthquakes: Quakes are created when forces within the crust build up strain in rock until something slips. Alaska is seismically active because a North Pacific crustal plate is ramming into southern Alaska, creating pressures that must be relieved at some point.

However, these pressures do push up high mountains where glaciers form - and the weight of the glaciers pushing down can stabilize the situation, if not eliminate the risk altogether. Remove that weight, and the likelihood of a quake goes up as the strain accumulates.

That's what happened with the 7.2 magnitude quake in Alaska's St. Elias region in 1979, Sauber and Dr. Molnia believe. Photographs show how glaciers in the fault area had thinned substantially during the 80 years since the previous earthquake activity.

Sauber says it now is clear that "in areas like Alaska where earthquakes occur and glaciers are changing, their relationship must be considered to better assess earthquake hazard." She adds that satellites are helping seismologists do this "by tracking the changes in extent and volume of the ice and movement of the Earth."

Another nonwarming implication of global warming is plant growth. Because plants use the carbon in CO2 to make their food and structures, they should grow faster as concentrations of the greenhouse gas go up. Many experts hope this will take some of the excess CO2 out of the air. They count on increased nitrogen fixation to supply the extra nitrogen to fertilize the plants.

Not so fast, warn Bruce Hungate at Northern Arizona University in Flagstaff. The experiments of Dr. Hungate and his collaborators show that this expected boon soon turns sour.

After burgeoning for a couple of years, the nitrogen fixers begin to lose their fixing ability. It looks as though molybdenum - a key nutrient - becomes less available as elevated CO2 levels change soil chemistry.

"Our results ... caution against expecting increased biological [nitrogen] fixation to fuel terrestrial [carbon] accumulation," the team warned in reporting its results in the journal Science last spring. The results also show the need for scientists to broaden their perspective when trying to foresee how Earth's ecosystems will respond to global change, the team added.

To adapt the financial guru's mantra, the way things worked in the past is an unreliable guide for expectations of how our planet will respond as humans force more unnatural change upon it.

 


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