Connection Between Global Warming & Cold Weather

Heidi Cullen, visiting lecturer at Princeton University and CEO of the nonprofit science journalism organization Climate Central, says melting sea ice could actually cause a paradox that can produce cold, snowy winters in some areas in the midst of a worldwide warming trend.

Cullen says researchers believe that the melting sea ice exposes more of the ocean's surface, releasing more warm moisture into the atmosphere, where it them meets colder, arctic air and condenses, producing snow. She says that may be difficult for most people to grasp, but researchers do expect global warming to produce more extreme weather, and she believes it's consistent with that. She says warming will also produce other extremes, like heat and drought.

Cullen compares the climate system to an orchestra. She says natural climate variations like El Nino. La Nina and the North Atlantic Oscillation are like different instruments, and warming is a constant drumbeat in the background that works it way into the weather. The byproduct of warming is more extreme weather.

It's important to make distinctions, Cullen says, between time scales on which different climate phenomena are measured. She says ice ages can be measured in centuries, while global warming can be measured from year to year. She says scientists have also been able to “fingerprint” the amount of carbon dioxide in the air, so they can say that one out of four CO2 molecules in the air were put there by processes such as burning fossil fuels. She says that makes the climate trends of the past few decades the appropriate time scale to use.

Cullen says recent events spawned by global warming can be considered “glimpses of the future.” She cites the European heat wave of 2003, when 30,000 to 40,000 people died. If we do not take action to stop global warming, Cullen says, we can expect such events to take place every other year. She says extreme climate events like that can be expensive, and working to reduce carbon emissions can reduce that expense. But she says there also needs to be an investment in infrastructure so people can adapt to the effects of climate change.

Cullen believes warming can be slowed by adopting policies like a clean energy standard, diversifying energy sources to include more renewables and investing in energy infrastructure. Or every dollar spent up front to improve infrastructure, she says, four dollars can be saved in the long run.

Cullen says there always has been extreme weather and it will always continue. But she believes that global warming will increase the severity of those extremes, and that's where the danger lies.