Monday, August 07, 2017

How sensitive is Rochester to Climate Change?

“The best available climate science and supporting research indicate that the key climate stressors for Rochester are warmer summers, increasing storms, warmer waters, colder winters, and increasing drought.” (Page 24, Rochester’s Climate Action Plan)

Scientists have been telling us for some time now that our climate system is very sensitive to energy input. Trapping more energy (heat) from the sun with our greenhouse gas emissions from the mid-1800’s has already produced unprecedented wildfires, floods, and extreme weather around the world. Even if we stop emitting more of these emissions right now, we are still likely to overshoot the Paris Accord goal of 2C by the end of this century. This will make us very vulnerable.

EARTH WILL WARM TWO DEGREES THIS CENTURY, SCIENTISTS PREDICT Researchers have confirmed that Earth is likely to warm by more than 2 degrees by the end of the century, an increase often cited as a “tipping point” by climate scientists—and one that people should try to avoid by limiting greenhouse gas emissions. In findings published Monday in Nature Climate Change, University of Washington researchers show a 90 percent chance that temperatures will have increased by 3.6 to 8.8 degrees Fahrenheit (2.0 to 4.9 degrees Celsius) by the end of the 21st century. Using statistical projections based on 50 years’ worth of past data in countries around the world, they found just a 5 percent chance that Earth will warm by 2 degrees or less in the next eight decades. As far as staying within the target set by the 2016 Paris agreement—an increase of 1.5 degrees or less—the researchers put the chances of that becoming a reality at a mere 1 percent. (July 31, 2017) Newsweek [more on Climate Change in our area]  

Like our planet, our bodies are sensitive to heat, making us vulnerable outside a relatively narrow range of temperatures. Although over the span of our specie’s existence we have learned to tolerate an incredible range of discomfort due to the weather through clothing and shelter, mostly we don’t tolerate temperatures that are too hot or too cold.

As we encounter Climate Change, we are learning that we may have actual limits on how much heat our body’s air conditioning system can handle. It looks as though 95F at 90% humidity might be our limit. (Or, because it’s a sliding scale, 100F at 85%.) This means that even if you’re fit, shaded, and in an area well ventilated, heat can kill.

Heat Waves Creeping Toward Deadly Heat-Humidity Threshold As global temperatures rise, river valleys in South Asia will face the highest risk of heat waves that reach the limits of human survivability, a new study shows. If global warming continues on its current pace, heat waves in South Asia will begin to create conditions so hot and humid that humans cannot survive outdoors for long, a new study shows. The deadly heat would threaten millions of vulnerable people in some of the world's most densely populated regions in India, Pakistan and Bangladesh—low-lying river valleys that produce most of the region's food. About 1.5 billion people live in the crescent-shaped region identified as the highest-risk area in a new study by scientists from the Massachusetts Institute of Technology and Loyola Marymount University in Los Angeles. The researchers combined global and detailed regional climate models to show where the most extreme conditions are expected by the end of this century. The researchers focused on a key human survivability threshold first identified in a 2010 study, when U.S. and Australian researchers showed there is an upper limit to humans' capacity to adapt to global warming. That limit is expressed as a wet-bulb temperature, which measures the combination of heat and humidity for an index of physical human misery. When the wet-bulb temperature goes above 35 degrees Celsius, the body can't cool itself and humans can only survive for a few hours, the exact length of time being determined by individual physiology. (August 2, 2017) Inside Climate News[more on Climate Change in our area]

For those of us living in Rochester, we are unlikely to be experiencing these kinds of temperatures soon. But what about the future?

Measuring Rochester’s sensitivity to Climate Change

Rochester’s Climate Action Plan (CAP) explains how we measure our sensitivity to various Climate Change scenarios and the degree to which various situations leave us vulnerable.

If an exposure is determined to have a high sensitivity and a low adaptive capacity, the vulnerability for that exposure would be high .... Whereas, if the adaptive capacity for that same exposure were to have a high sensitivity but low adaptive capacity, the vulnerability would be high. (See Table 3: Climate Vulnerabilities for City of Rochester, page 25 CAP)

The city of Rochester’s vulnerability is high if the Climate Change impact is increased infrastructure maintenance, increased infrastructure disruptions due to extreme weather events, decreased food production, increased crop loss, higher intensity of heating and cooling degree days, increased diseased concerns, air quality impacts on health, and loss of winter recreation activities. Our vulnerability is low if we only experience increased water demand and cost, increased pollutant toxicity, and a longer composing season. (Page 25, CAP)

Caution: level of vulnerability matrixes includes inherent moral hazards

While it is necessary for our authorities and institutions to present their stakeholders (other groups and even the public) with possible climate vulnerabilities, there is an inherent moral hazard when we try to quantify environmental service cost/benefits, in general or in the specific case of Rochester. First, the public (who has not examined this crisis in depth) tend to think that the list of vulnerabilities is exhaustive. That is, because we need actionable items that aren’t overwhelming (financially and psychologically), we tend to act as if we’ve captured all the possible vulnerabilities that warming up our climate will have on our region. As a result, we decide which on the list to worry about and act accordingly. But we might have missed many of the things that put us at risk. Many times, we miss vulnerabilities because we don’t know how to quantify them—for example, soil degradation and ecosystem health -- so we leave them off. In other words, there’s an inherent moral hazard with vulnerability matrixes because we may be deluding ourselves into a dangerous complacency. Just because we don’t have data on environmental problems doesn’t mean they don’t exist.  

Another issue with attempts to quantify Climate Change vulnerabilities is that our environmental records don’t go back very far. When our ancestors came to this region, they did not do a baseline study of what an undisturbed environment looks like—before they started changing it. They did not understand ecological health as they ‘tamed’ our lands and seas in their pursuit of progress. Some of our oldest records are with ice coverage dates on some lakes—how early the ice came and how long it stayed before melting in the spring. But even these aren’t very old. This is to say, even our most comprehensive plans to assess our sensitivity to Climate Change disruptions is probably going to be missing critical information. (We tend see our environment as it serves our needs, not how it operates independently of us.)

Also, because these matrixes are worked up for specific regions, we tend to forget how the actions or inactions of other communities, nearby or further flung, will impact our ability to measure our own vulnerabilities. (For example, if everyone in Rochester dramatically reduced their greenhouse gas emissions and the surrounding Monroe County resumes business as usual, what we do may not have much overall effect.) Our political boundaries may be specific, but our environmental boundaries are always planet-wide.  

This doesn’t mean that it’s hopeless working with local vulnerability matrixes; it means we need to get Monroe County, all of New York’s Counties, our nation, and other nations working together if we are going to characterize this crisis correctly.  

We don’t really know how sensitive Rochester is to Climate Change

We’ve never been through a phenomenon like Climate Change. Although we may not know exactly how sensitive Rochester is to Climate Change, we know enough to know that it’s important that we get moving. Addressing Climate Change is likely to be more challenging than our best laid plans predict. But, given our capacity for adaptation, we are more likely to rise to those challenges once we begin the journey towards a sustainable future.

One thing is for sure. If we ignore responsible community action plans like Rochester’s CAP and continue business as usual, all those other things we want for ourselves and our children probably won’t happen.

Time passes.

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