The south Pacific near the equator, a little west of Peru, swells in temperature around Christmastime every few years. El Niño (Spanish for little child) visited only that tiny area this winter, but even here at Penn State, we began to see daffodils blossom early in March. David Call, an undergraduate in Penn State's meteorology program, thinks the two events are linked.
As early as 1525, Francisco Pizarro wrote about unusual desert rainfall affecting vegetation and intense floodwaters lapping against the shores of Peru. But accurate weather observations only date back to the 1800s. To figure out if El Niño has anything to do with a Pennsylvania winter, Call delves deep into these archives of temperature data, plucking numbers from yellowing books and feeding them into Microsoft Excel.
He'd rather be chasing storms, but he feels that this research will help society. Knowing the weather in advance can help emergency teams gear up for incoming storms, cities budget for snow removal, and utility companies estimate energy needs. "If we can say with confidence and back it up with statistical information that Pennsylvania will be in for winters, say, five degrees above normal temperature, then that can go a long way towards planning," says Call.
Historians believe El Niño may have helped the Spanish conquer the Inca Empire. It continues to affect not only South American societies, but North American ones as well. This year, 48 out of 50 counties in California became disaster areas due to storms, and Florida suffered tornadoes in February. In the north, Pennsylvanians soaked in the mild sun, while Minnesotans had to cancel their annual ice festival. How do the fishermen feel about this natural heating system in their waters? It means good news for the Mexicans, but not so good news for the Peruvians. "In Peru, all their normal fish die because the water's too warm," says Call. "But people in Mexico can all of a sudden catch anchovies."
El Niño might not affect the weather day to day, but the overall climate of a place could temporarily shift—toward a warmer winter, for example.
"All weather systems are interrelated," says Call. A storm develops over the Gulf of Mexico, then moves out toward northern Florida and Georgia. In the northern and southern hemispheres, the Pacific Ocean churns like gears grinding against each other. Caught in the middle, El Niño enhances disturbances all along the western coastline of North and South America. Due to El Niño's warm water, the normally weak storms gather strength once they creep along the shores of North America. After that, the storms freely swirl to California. "It's like dominoes," he says, explaining what happens when oceanic winds disrupt each other. "Tinker with one domino and the whole thing's changed."
Though Call has always been awed by clouds and has been an avid watcher of the Weather Channel, he didn't become a true weather-weenie until he came to Penn State. He hopes to work as a meteorologist at a local news station. "In meteorology, half the battle is getting people aware," says Call. "But the whole thing's gotten overhyped—you'd think El Niño was responsible for everything. It's better to get the story from me than from the media." You can blame El Niñofor trends, like an overall warmer winter or more rainfall over a period of time, Call explains. But if it pours on Monday, or the temperature drops to 45 after a week of sunbathing, that's not El Niño, that's just the weather.
David Call is a meteorology major in the College of Earth and Mineral Sciences. His adviser is Gregory Forbes, Ph.D., associate professor of meteorology, 503 Walker Building, University Park, PA, 16802; 8148632458; gsf3@psu.edu.