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In a recent post on his Weather Underground blog, meteorologist Dr. Jeff Masters takes readers on a tour of the “top twenty most remarkable weather events of 2010”:

• Earth’s hottest year on record
• Most extreme winter Arctic atmospheric circulation on record: “Snowmageddon” results
• Arctic sea ice: lowest volume on record, 3rd lowest extent
• Record melting in Greenland, and a massive calving event
• Second most extreme shift from El Niño to La Niña
• Second worst coral bleaching year
• Wettest year over land
• Amazon rainforest experiences its 2nd 100-year drought in 5 years
• Global tropical cyclone activity lowest on record
• A hyperactive Atlantic hurricane season: 3rd busiest on record
• A rare tropical storm in the South Atlantic
• Strongest storm in Southwestern U.S. history
• Strongest non-coastal storm in U.S. history
• Weakest and latest-ending East Asian monsoon on record
• No monsoon depressions in India’s Southwest Monsoon for 2nd time in 134 years
• The Pakistani flood: most expensive natural disaster in Pakistan’s history
• The Russian heat wave and drought: deadliest heat wave in human history
• Record rains trigger Australia’s most expensive natural disaster in history
• Heaviest rains on record trigger Colombia’s worst flooding disaster in history
• Tennessee’s 1-in 1000 year flood kills 30, does $2.4 billion in damage 

And addresses some key questions regarding the influence of climate change: 

The pace of extreme weather events has remained remarkably high during 2011, giving rise to the question—is the “Global Weirding” of 2010 and 2011 the new normal? Has human-caused climate change destabilized the climate, bringing these extreme, unprecedented weather events? Any one of the extreme weather events of 2010 or 2011 could have occurred naturally sometime during the past 1,000 years. But it is highly improbable that the remarkable extreme weather events of 2010 and 2011 could have all happened in such a short period of time without some powerful climate-altering force at work. The best science we have right now maintains that human-caused emissions of heat-trapping gases like CO2 are the most likely cause of such a climate-altering force.

Human-caused climate change has fundamentally altered the atmosphere by adding more heat and moisture. Observations confirm that global atmospheric water vapor has increased by about 4% since 1970, which is what theory says should have happened given the observed 0.5°C (0.9°F) warming of the planet’s oceans during the same period. Shifts of this magnitude are capable of significantly affecting the path and strength of the jet stream, behavior of the planet’s monsoons, and paths of rain and snow-bearing weather systems. For example, the average position of the jet stream retreated poleward 270 miles (435 km) during a 22-year period ending in 2001, in line with predictions from climate models. A naturally extreme year, when embedded in such a changed atmosphere, is capable of causing dramatic, unprecedented extremes like we observed during 2010 and 2011. That’s the best theory I have to explain the extreme weather events of 2010 and 2011—natural extremes of El Niño, La Niña and other natural weather patterns combined with significant shifts in atmospheric circulation and the extra heat and atmospheric moisture due to human-caused climate change to create an extraordinary period of extreme weather.

Check out the rest of the article here.