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Accurate and reliable gridded datasets are important for analyzing extreme weather and climate events. Specifically, these datasets should produce extreme value statistics that are close to reality. Here we use various statistical methods to evaluate the quality of four gridded data products in representing daily precipitation extremes. The data products are the COSMO-REA6 regional reanalysis, the ERA5 global reanalysis, and the E-OBS and HYRAS gridded observation-based datasets. The statistical methods we use offer a thorough insight into the quality of the different datasets by providing temporal and spatial extreme value statistics of daily precipitation. Our results show that all datasets except HYRAS underestimate the magnitude of daily precipitation extremes when compared with weather station data. Moreover, the reanalysis datasets give generally worse extreme value statistics of daily precipitation than the gridded observation-based datasets. In particular, the reanalysis datasets often fail in reproducing the accurate timing of observed daily precipitation extremes.

[1] Many paleoclimatic data reveal a ∼1,500 year cyclicity of unknown origin. A crucial question is how stable and regular this cycle is. An analysis of the GISP2 ice core record from Greenland reveals that abrupt climate events appear to be paced by a 1,470-year cycle with a period that is probably stable to within a few percent; with 95% confidence the period is maintained to better than 12% over at least 23 cycles. This highly precise clock points to an origin outside the Earth system; oscillatory modes within the Earth system can be expected to be far more irregular in period.

Extreme weather and climate events provide dramatic content for the news media, and the past few years have supplied plenty of material. The 2004 and 2005 Atlantic hurricane seasons were very active; the United States was struck repeatedly by landfalling major hurricanes. A five-year drought in the southwestern United States was punctuated in 2003 by wildfires in southern California that caused billions of dollars in losses. Ten cyclones of at least tropical storm strength struck Japan in 2004, easily breaking the 1990 and 1993 records of six cyclones each year. Hurricane Catarina was the first recorded hurricane in the South Atlantic. Europe's summer of 2003 saw record-breaking heat that caused tens of thousands of deaths.

With the turning of the calendar, a number of groups have announced their man or woman of the century or even of the millennium, while others have issued top 10 lists. In mid-December the U.S. National Oceanic and Atmospheric Administration released its list of the top U.S. and global weather, water, and climate events of the 20th century.

Some drastic climate events during the past year alone (March blizzard, mid-western flooding, intensifying El Nino) have raised even more concern lately about the effects of global environmental change, which may in part be caused by an increase in greenhouse gases in the atmosphere. “We could see changes in climate greater than any we've seen in the past 10,000 years,“ said Katie McGinty, director of the White House Office of Environmental Policy. Addressing the attendees of a meeting entitled “Global Change: A New Direction for Decision Making,” held October 27–28 in Washington, D.C., where representatives of some federal science agencies, among others, presented their views on global environmental change policy and scientific issues, McGinty noted that the Clinton Administration is bringing a new direction to global change policy.