El Niño and La Niña are counterparts in the El Niño-Southern Oscillation (ENSO), a cyclic warming and cooling of the eastern and central Pacific Ocean that exerts a major influence on global weather patterns, but they are not mirror images.
A team of scientists led by NCAR’s Keith Oleson has incorporated urban areas into a global climate model. The development is important because most models used for predicting future climate change do not account for the urban “heat island” effect.
In 1988, it was the spectre of Yellowstone National Park on fire. In 2003, it was the horror of thousands dying from heat in prosperous western Europe. The planet’s standout heat wave in 2010 plagued much of European Russia, including Moscow.
In Kansas City and Tulsa, overnight lows have seldom dipped much below 80°F, with consistently oppressive humidity. Pulses of tropical air flowing north and east from the Gulf of Mexico are largely to blame.
During the stormy summer of 2005, hurricanes Katrina and Rita raised concerns about the potential effects of global warming on tropical cyclones. At the same time, the Amazon rainforest was experiencing one of its most intense droughts of the last century.
Years before Congress began debating greenhouse-gas reduction, more than 500 U.S. cities had pledged to reduce their carbon footprints in line with the goals of the Kyoto Protocol. Now American cities are leading the way on adapting to climate change.
In eastern Tennessee a portrait of Earth's progression from ice age to present is taking shape. Each day, up to 100 years of climatic history unfolds. By early this year, the story will be complete, thanks to some five million processing hours on supercomputers at the Oak Ridge National Laboratory.
A growing body of research now confirms that the Montreal agreement averted at least one catastrophic form of climate change, even if others still loom. "The Montreal Protocol is a major success story," says William Randel.
In a vivid example of how a small geographic feature can have far-reaching impacts on climate, new research shows that water levels in the Bering Strait helped drive global climate patterns during ice age episodes dating back more than 100,000 years.