Not caused by; made more intense by, which is what you would expect with hotter water temps and 4% more water in the air.
Records [ edit]
Known Atlantic hurricanes with gale diameter of 750 miles
StormSeasonDiameter(mi)(km)Sources: [1], [2], [3], [4]The storm surge produced by Hurricane Sandy, which occurred at high tide, pushed water to 13.88 ft (4.23 m) at Battery Park, New York, beating the previous record of 10.02 ft (3.05 m) set by Hurricane Donna in 1960 at the same location. However, a storm surge of 13 feet, during low tide, was also reported at Battery Park during the 1821 Norfolk and Long Island hurricane, which occurred before records were officially kept. [48] Storm tide records were also broken in Sandy Hook, New Jersey and Philadelphia, Pennsylvania, with peak tides of 13.31 ft (4.06 m) and 10.62 ft (3.24 m), respectively. The tidal gauge in Sandy Hook lost power while the tide was still rising, meaning the tide crested higher than the recorded peak. [49] A buoy in New York Harbor reached a record height when it measured a 32.5-foot (9.9 m) wave on October 30,7.5 feet (2.3 m) taller than a 25-foot (7.6 m) wave registered by Hurricane Irene in 2011. [50]
Sandy was the largest tropical cyclone in terms of gale diameter since records began in 1988. [51] In addition, at 945 millibars (27.9 inHg), Sandy was second only to 1938 New England hurricane for the most intense storm to hit land in the United States north of Cape Hatteras, North Carolina. [52] The barometric pressure hit a record low of 945.5 mbar (27.92 inHg) over Atlantic City, New Jersey, breaking the previous record of 961 mbar (28.4 inHg) set in 1938. [53] Sandy also broke the record for producing the lowest pressure in Philadelphia, with a minimum of 954 mbar (28.2 inHg); the previous record was 962 mbar (28.4 inHg), set during the 1993 Storm of the Century. [49]
Global warming effect [ edit]
Evening photo of Sandy on October 28
Climate scientists agree that climate change increases the likelihood of stronger and wetter storms, though possibly leading to fewer of them. However, researchers were unable to say just how responsible climate change was for the development and track of Sandy. [54] Tropical cyclones derive their energy from warm waters, and warmer water generally mean stronger storms. Climate change has caused sea levels to rise, which made the storm surge and coastal flooding caused by Sandy much more devastating. Since the overall sea level has risen by 8 in (20 cm) between 1902 and 2007, and is accelerating, [55] the rise in sea level increases the risk for major floods to occur every time a storm hits. A 2012 paper in Nature projected that climate change could lead to floods that should occur only once a century to happening every three to twenty years. [54]
In the case of Hurricane Sandy, two major factors contributing to the size and strength of the storm were unusually warm ocean surface temperatures and an increase in blocking patterns, both of which are expected to occur more frequently due to global warming. [56] [57] As they drift north, Atlantic hurricanes are typically moved to the east and out to sea by the jet stream's prevailing winds. [58] This typical pattern was blocked by a ridge of high pressure over Greenland, resulting in a negative Arctic oscillation, forming a kink in the jet stream and causing it to double back on itself off the East Coast; Sandy was caught up in this northwesterly flow. [58] The blocking pattern over Greenland also stalled an arctic front, which combined with the cyclone. [58] Mark Fischetti of Scientific American argued that the jet stream's unusual shape was caused by the melting of Arctic ice. [59] Noting that these blocking patterns are unusual in the fall but have been increasing, meteorologist Jeff Masters said that three studies in 2011 found "that the recent record decline in Arctic sea ice could be responsible, since this heats up the pole, altering the Equator-to-pole temperature difference, forcing the jet stream to slow down, meander, and get stuck in large loops." [58] Trenberth said that while a negative Arctic Oscillation and a blocking anticyclone were in place, the null hypothesis remained that this was just the natural variability of weather. [60]
Sandy, as seen by the Suomi NPP satellite on October 30, over the eastern United States and Canada
Climatologist Michael E. Mann attributes at least one foot of the 13-foot (at least 0.3 of the 4-meter) storm surge in Lower Manhattan to global sea level rise. [61] Harvard geologist Daniel P. Schrag calls Hurricane Sandy's 13-foot storm surge an example of what will, by mid-century, be the "new norm on the Eastern seaboard". [62]
According to National Center for Atmospheric Research (NCAR) senior climatologist Kevin E. Trenberth, "The answer to the oft-asked question of whether an event is caused by climate change is that it is the wrong question. All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be." [63] He illustrates by pointing out that steroids in a baseball player's system do not cause home runs all by themselves but do make home runs more likely. [64] Meteorologist Kerry Emanuel stressed that no individual weather event, such as Hurricane Sandy, can be attributed to climate change, or any specific cause, for that matter. [65]
NOAA meteorologist Martin Hoerling attributed the "immediate cause" of Sandy to "little more than the coincidental alignment of a tropical storm with an extratropical storm." [60] Trenberth agrees that the storm was caused by "natural variability", but adds that it was "enhanced by global warming". [56] One factor contributing to the storm's strength was additional energy from abnormally warm water off the North American East Coast, where global warming was identified as contributing 1.08 °F (0.6 °C) of the 5.4 °F (3 °C) above-average sea surface temperatures. [56] As the temperature of the atmosphere increases, the capacity to hold water increases, leading to stronger storms and higher rainfall amounts. [66]
US Republican Henry Waxman, the top Democrat on the House Energy and Commerce Committee, wanted Republicans to hold a hearing on links between climate change and Hurricane Sandy. "Hurricane Sandy is exactly the type of extreme weather event that climate scientists have said will become more frequent and more severe if we fail to reduce our carbon pollution. That is why we are writing to request that you hold a hearing on the storm and its relation to climate change in the lame-duck session", he and Congressmen Bobby Rush wrote. [67] The hearing was not presented before the senate and house prior to the emergence of the new Congress in early 2012. On April 9, 2013, however, Waxman and Rush renewed their request of a hearing, stating that, "If we rely upon representatives of electric utilities, coal companies, oil refiners, and chemical manufacturers to explain the state of the science regarding climate change, we are unlikely to get a full and unbiased view of the challenge we must confront and the opportunities we have.” [68]
en.wikipedia.org |
