The best continental record of global climate change over the past 2.5 million years may have a more complicated story to tell than previously believed, according to a team of UC Davis geologists and soil scientists. They recently discovered a way to read certain "chapters" of that story once thought to be the equivalent of blank pages. The geological record under investigation exists in China, where rivers have cut through an expansive plateau to expose skyscraper-tall cliffs layered with sediments. The richer, darker ribbons represented soils that scientists thought could only have been formed during warmer, wetter periods. Wider, lighter taupe bands known as loess have been thought to represent cooler, drier glacial periods. But geology professor Kenneth Verosub and soils professor Michael Singer, with the help of their graduate students and postdoctoral fellow, have found evidence for the first time of soil formation processes within the loess. This means there may be more details of climate change to be discovered within those periods. These findings were published in a recent cover article in the journal Geology.