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. Trends in local events like hail and thunderstorms were also inconclusive. As for droughts, the IPCC noted that its previous conclusions about increasing trends were overstated and that “the compelling arguments both for and against a significant increase in the land area experiencing drought has hampered global assessment.” Data for tornado activity in the U.S. shows tornadoes occur no more frequently now than in the past and that the number of strong tornadoes (F3 and above) has actually decreased. Sea Ice, Glaciers, and Ocean Acidification. Another mainstay of the climate change alarmism movement is that glaciers are melting, sea levels are rising, and the oceans are acidifying, which will disrupt ocean life and the food chain. Again, the data does not support such doomsday scenarios. Sea Ice and Glaciers. Only since the beginning of the era of satellite measurement (1979) have we had comprehensive, accurate data on sea-ice extent at the poles. Although there is significant season-to-season and year-to-year variability of world sea-ice coverage, there is no dramatic trend inglobal sea-ice loss. In general, the much-hyped downward trend in Arctic sea ice has been offset by a similar increase in Antarctic sea ice. The peak sea-ice area in 1979 was about 22 million square kilometers. The peak sea ice in 2015 was a little over 21 million square kilometers, with the intervening period having some years with peaks above that of 1979 and some with dips below that of 2015. In any event, it would not be surprising to find a slight downward trend for sea ice as the late 1970s came at the end of a decades-long period of slight global cooling. While we do not have satellite records for that earlier period, it is likely that sea-ice extent was greater in 1979 than it had been decades earlier. It is also worth noting that sea ice is floating ice. The 23-century-old Archimedes Principle holds that when floating ice melts, it will not appreciably affect sea level. Permanent land ice is the defining feature of an ice age. Glaciers, the remnants of the ice ages, still persist at high elevations and high latitudes. Glaciation has retreated dramatically since the last ice age, though the retreat has not been at a constant rate and sometimes goes in reverse (sometimes for thousands of years). These rates and reversals vary by time and by region. In addition, it should be noted that factors other than average world temperature can change the size of glaciers. Sea Levels. Though every year seems to bring on a prediction of imminent sea-level rise more dire than the last, the observed reality does not reflect this. Corresponding to the recovery from the Little Ice Age, sea level has risen about eight inches in the past 130 years.