Analys: ”Harvey visar hur klimatförändringen ser ut”

Hurricane Harvey is an active tropical cyclone that is causing unprecedented and catastrophic flooding in southeastern Texas. It is the first major hurricane to make landfall in the United States since Wilma in 2005, ending a record 12-year period with no hurricanes of Category 3 intensity or higher making landfall in the United States. Harvey is the first hurricane to make landfall in the state of Texas since Ike in 2008, and the strongest to make landfall in the state since Carla in 1961. In addition, it is the strongest hurricane in the Gulf of Mexico since Hurricane Rita in 2005, and the strongest to make landfall in the United States since Hurricane Charley in 2004. Harvey is also the wettest tropical cyclone on record in the contiguous United States dropping nearly 52 inches (1,300 mm) of rain, surpassing a record set by Tropical Storm Amelia in 1978. The eighth named storm, third hurricane, and the first major hurricane of the 2017 Atlantic hurricane season, Harvey developed from a tropical wave to the east of the Lesser Antilles, reaching tropical storm status on August 17. The storm crossed through the Windward Islands on the following day, passing just south of Barbados and later near Saint Vincent. Upon entering the Caribbean Sea, Harvey began to weaken due to moderate wind shear and degenerated into a tropical wave north of Colombia early on August 19. The remnants were monitored for regeneration as it continued west-northwestward across the Caribbean and the Yucatán Peninsula, before redeveloping over the Bay of Campeche on August 23. Harvey then began to rapidly intensify on August 24, regaining tropical storm status and becoming a hurricane later that day. While the storm moved generally northwest, Harvey's intensification phase stalled slightly overnight from August 24–25, however Harvey soon resumed strengthening and became a Category 4 hurricane late on August 25. Hours later, Harvey made landfall near Rockport, Texas, at peak intensity. Harvey has caused at least 19 confirmed deaths; 1 in Guyana, and 18 in the United States. Catastrophic inland flooding is ongoing in the Greater Houston area. FEMA director Brock Long called Harvey the worst disaster in Texas history, and expected the recovery to take many years. Preliminary estimates of economic losses range anywhere from $10 billion to $50 billion. Moody's Analytics has the estimate of between $40 billion to $50 billion in damages due to the storm.

Klimatförändring är variationer av jordens klimat över tiden, lokalt eller globalt. När sådana iakttagna fluktuationer bildar en trend över tidsperioder som sträcker sig över alltifrån decennier till miljontals år, talar man om klimatförändringar. Sådana förändringar kan ha naturliga orsaker som variationer i solaktivitet eller geologiska processer men kan också vara antropogena. I modernt språkbruk används termen främst för att beskriva den senaste tidens klimatförändringar, i synnerhet den temperaturstegring som kallas global uppvärmning. Fenomenet global avkylning som förekom under istiderna, räknas också in under begreppet klimatförändring.