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Five recent events stoking climate change fears
The Trump administration this month introduced rules that would roll back Obama-era regulations on vehicle emissions and coal fired plants, raising concerns in the scientific community about how a slower approach to decreasing carbon emissions will affect the world's climate.
Arctic melting, raging forest fires and increasingly brutal summer temperatures are just a handful of the signs that climate change may have transitioned from a lingering threat to a phase where it might be too late to mitigate some of its effects.
Here are five recent events and developments stoking climate change fears.
Arctic's thickest ice layer breaks for first time on record
The oldest sea ice in the Arctic Ocean, in the most northern parts of the planet, began breaking up this summer for the first time in recorded history. The area off the north coast of Greenland is usually a frozen sheet of ice -- so solid that scientists referred to it as "the last ice area," an assumption that it would resist the melting caused by climate change.
Experts attribute this summer's unprecedented phenomenon to warm winds and a rise in temperatures caused by the recent heatwave in the Northern Hemisphere. Large ice chunks in the region have pushed the ice sheet the farthest distance from Greenland's coast since record-keeping began in the 1970s. Scientists say the significant shift will lead to quicker melting, contributing to rising sea levels.
"I cannot tell how long this open water patch will remain open, but even if it closes in few days from now, the harm will be done: the thick old sea ice will have been pushed away from the coast, to an area where it will melt more easily," Thomas Lavergne, a scientist at the Norwegian Meteorological Institute, told The Guardian.
Longer fire seasons contribute to historic forest fires
Western states for the second year in a row are experiencing some of the largest wildfires on record. The Mendocino Complex Fire became the biggest fire in the state's history, burning 366,086 acres as of Thursday, with 67 percent of the fire contained. The Thomas Fire in Ventura last year, now the second-biggest fire, burned 281,893 acres.
Other fires, north of Seattle and in Montana, have raised concerns about the effect of increased drought and warmer temperatures during the fire season.
A NASA study published in 2015 found that fire seasons were getting longer and more frequent, with fire seasons being lengthened across 25 percent of Earth's vegetated surface.
The U.S. Forest Service website calls "longer fire seasons; bigger fires and more acres burned on average each year; more extreme fire behavior" the new "norm."
For some scientists, the evidence is inconclusive as to whether climate change is driving an increased frequency of fires, yet many studies link climate change to the drought that continues to plague a number of western states. That drought has been said to help propel fires that easily burn through dry brush and water-barren lands.
Hurricanes hit with more frequency and intensity
Hurricane Lane, which dumped more than 30 inches of rain in parts of Hawaii this week, is the latest example of an increase in the number of storms hitting the U.S.
Over the past year, three historic hurricanes -- Harvey, Irma and Maria -- made landfall in the U.S., leading to billions of dollars of damage and 1,427 deaths in Puerto Rico alone.
A study released in June by the National Oceanic and Atmospheric Administration (NOAA) estimated that rising global temperatures caused in part by manmade climate change give "better than even odds that anthropogenic warming over the next century will lead to an increase in the occurrence of very intense tropical cyclones."
However, the report also said it was premature to conclude that greenhouse gas emissions have created a "detectable impact" on hurricanes.
NOAA's study estimated that the intensity of storms is also being driven in part by rising temperatures from carbon emissions. The federal agency estimated that the intensity of storms globally will likely increase on average between 1 percent and 10 percent, suggesting an even larger percentage increase in property destruction and loss of life.
Heat waves paralyze cities worldwide with record-setting temps
Major cities across the globe in June experienced some of the warmest temperatures in recorded history. Montreal, Glasgow and Shanghai were all hit with record highs.
Meanwhile, a town in Algeria set the continent's highest reliably recorded temperature, at 124.3 degrees, according to figures compiled by the Washington Post, while Burlington, Vt., set its all-time warmest low temperature of 80 degrees on July 2.
A few days earlier, Quriyat, Oman, set world's hottest low temperature ever recorded, at 109 degrees.
During the period, abnormally warm temps hit Western Europe, leaving typically moderately warm cities blazing hot, creating a run on air conditioners and even fans in some cities.
While scientists say you cannot attribute singular weather events to a larger pattern of global warming, the worldwide records offered a glimpse of what a warming world looks like. The high temps are considered consistent with the type of weather extremes expected to be seen more frequently due to greenhouse gas emissions.
Toxic algae blooms close down beaches
A widespread epidemic of toxic algae blooms off the coast of several Gulf Coast beaches in Florida has lead to a number of closures and a state of emergency declaration by the governor.
The increase in toxic algae -- also known as red tide -- has made ocean conditions harmful to humans, while killing thousands of fish.
While red tide is a common phenomenon in the Gulf of Mexico on a smaller scale, scientists attribute the increased size and locations of blooms to global warming. Warming waters cause the red algae to grow faster and larger, using up a majority of the dissolved oxygen in the water. That, in turn, kills off ocean inhabitants who can't survive without the dissolved oxygen.
The blooms were attributed to the death of a 26 foot whale shark that washed up on Florida's Sanibel Island in July.
The presence of red algae in the Great Lakes is also worrisome to scientists. Blooms in Lake Eerie grew so big during the summer in recent years that they covered an area the size of New York City. The largest blooms were in 2011 and 2015. They adversely affected drinking water pulled from the lake.