According to the US Geological Service, this disruption can include the "extinction of temperature sensitive aquatic species." , there is a "high degree of confidence" that the Texas and Oklahoma heat waves and drought of 2011, and heat waves and drought in Moscow in 2010, "were a consequence of global warming" and that "extreme anomalies" in weather are becoming more common as a direct consequence of human-caused climate change.
Higher temperatures from global warming are also causing some mountainous areas to receive rain rather than snow.
They contend that immediate international action to reduce greenhouse gas emissions is necessary to prevent dire climate changes.
The con side argues human-generated greenhouse gas emissions are too small to substantially change the earth’s climate and that the planet is capable of absorbing those increases.
According to a 2013 IPCC report, there is "high confidence" (8 out of 10 chance) that changes in the sun's radiation could not have caused the increase in the earth's surface temperature from 1986-2008.
Although warming is occurring in the lower atmosphere (troposphere), the upper atmosphere (stratosphere) is actually cooling.
The study created the famous "hockey stick" graph, showing that the rise in earth's temperature over the preceding decade had occurred at a rate faster than any warming period over the last 1,700 years.
According to the IPCC’s 2014 Synthesis Report, human actions are "extremely likely" (95-100% confidence) to have been the main cause of 20th century global warming, and the surface temperature warming since the 1950s is "unprecedented over decades to millennia." , the sun has had only a "minor effect" on the Northern Hemisphere climate over the past 1,000 years, and global warming from human-produced greenhouse gases has been the primary cause of climate change since 1900.
Climate Central predicts that 147 to 216 million people live in areas that will be below sea level or regular flood areas by the end of the century if human-produced greenhouse gas emissions continue at their current rate.
As excess human-produced CO2 in the atmosphere is absorbed by the oceans, the acidity level of the water increases.