Climate Change 101

If you are reading this blog, or if you have listened to the news much in the past 20 years, you are probably already aware that there is a weather phenomenon known as Climate Change. Originally often referred to as Global Warming, climate change more accurately reflects the real-world consequence to humans.

As the planet warms, weather patterns become more severe. It may lead to hotter summers and drought. It may also lead to severe winter blizzards. Hurricanes, tornadoes and monsoons have more energy and are more frequent. In fact, the entire weather cycle has more energy overall, and all weather events become more pronounced.

Of course, depending on your source of news and your political leanings, you may not believe any of this is actually happening. Fortunately, most Americans, as with the vast majority of the world, now know something is amiss with our weather. The "controversy" over whether climate change is happening is largely a product of politics and fear-mongering. When 97% of the world's climate scientists agree with the U.S. Department of Defense, any practical debate of whether climate change is actually happening is essentially over. The debate still over WHY it is happening, how much of it is caused by humans and how much is naturally occurring, and what the consequences of this change will be is another story.

For long-term planning purposes including the investment of billions of dollars in infrastructure projects, we'd be crazy not to plan for certain known eventualities. Just as our military is making critical strategic decisions about how climate change will affect our ability to defend ourselves, our State and Federal planning boards must all make key decisions. Whether it is such projects as flood control in our rivers or coastal regions, planning and allocating water supplies, making improvements to our electrical grid, siting wind farms, protecting endangered or threatened species, locating crops, eradicating or minimizing the damage from agricultural pests, enacting fire suppression in our forests, or best determining how much CO2 can be released into the atmosphere, our governmental agencies must do their best to plan for effects that will not occur for twenty, fifty, perhaps even 100 years from now.

Modeling shows that the long-term effects of climate change have three very important components. First, they tend to be slow. Our planet is currently warmed from CO2 in the atmosphere that was released decades ago, and even if we stop burning fossil fuels today, the concentration of CO2 in the atmosphere will continue to rise for many years before the concentrations start to decrease. Second, these effects are profound. Although we cannot easily see them in our daily lives, the changes that have occurred over the last fifty years are dramatic. Whether it is the warming of the Earth as a whole, the dramatic warming of the North and South Pole, the migration of species to higher altitudes or different latitudes, the acidification of our oceans, coral reef bleaching, etc., the warming of our planet is affecting ecosystems world wide.

Perhaps the most important issue is that our computer modeling is imperfect. For example, 20 simulations of rainfall predicitions for California over the next 50 years may yield 1 result where California gets twice the rainfall that it has historically, 2 results where it gets less than half, and 17 results where CA gets 10-25% less. Which model is right? If you work for the Department of Water Resources, how do you plan your infrastructure projects? Does it make sense to plan for the worst-case scenario, or the scenario that is more statistically likely to happen? In this day of limited budgets and resources, can we afford to ignore the problem entirely, or just wish it away? In my next post, I will discuss some of the steps California is currently taking to prepare for its unknown water future.