The issue of global warming, or climate change, has gotten a lot stormier. For a while, it seemed that forecasts for uninterrupted warming—and catastrophe—were on track. That position reached its zenith in 2005 when hurricanes Katrina and Rita landed a one-two punch. There were fears these twin-bill storms were just the first of many disasters.
But if there's one thing we can count on, it's change. That's certainly the byword in the weather business—and that includes climate change debate. In the last two years, weather events have put long-term analyses into question.
Quiet season. Let's start with late summer 2006. Forecast after forecast predicted a hurricane season even more pronounced than the 2005 Katrina/Rita season. Yet 2006 proved to be tranquil. The reason? A late-summer El Nino Pacific Ocean temperature pattern developed. As a result, the strong jet stream winds in the tropics literally blew apart any tropical storm systems that tried to form in the Atlantic and Gulf basin.
The second example is the winter and spring temperature pattern of 2007/2008. Values were well below average over much of the U.S. And, in the Midwest, snow cover of almost 7 feet contributed extensively to spring flooding. This past spring, temperatures remained cold while rain saturated Midwestern soils.
As I spoke at farm meetings and conferences across the country, the same question was asked over and over: "If we have global warming, why is it so darned cold?"
What's ahead. We know that just relying on computer models for looking "way out" truly can be an inexact enterprise. But there is a dynamic resource that behaves on its own: the ebb and flow of temperature and energy in the oceans. I believe continued research focused on the world ocean currents and temperature changes will be a huge key in improving our assessment of climate change and cycles. We already know that changes in the ocean temperature patterns can be huge in driving the North America weather patterns. After all, such occurrences as El Nino or La Nina are well-known. But even more information is out there. As we learn more about how the ocean interacts with the atmosphere, we will learn more about what to expect on land.