Query: Forget what global warming activists would lead you to believe—2015 was not even close to the hottest year on record.

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Years of Living Dangerously <=SEP=> Years of Living Dangerously is an American documentary television series focusing on global warming . The first season , of nine weekly episodes , premiered in the US on April 13 , 2014 , on Showtime . It won an Emmy Award as Outstanding Documentary or Nonfiction Series . The second season , consisting of eight episodes , aired on the National Geographic Channel , beginning on October 30 , 2016 , with broader international distribution than the first season . Executive producers included James Cameron , Arnold Schwarzenegger , Robert Palumbo , and series creators Joel Bach and David Gelber ( formerly of 60 Minutes ) . Joseph Romm and Heidi Cullen were the chief science advisors .   The weekly episodes featured celebrity hosts with a history of environmental activism and well-known journalists with a background in environmental reportage . These `` correspondents '' traveled the world and throughout the U.S. to interview experts and ordinary people affected by , and seeking solutions to , the effects of global warming . They acted as reporters and proxies for the audience , asking questions to find out people 's opinions and to discover the scientific evidence . The final episode of season one featured an interview of President Barack Obama . Executive producers for season one were Cameron , Schwarzenegger , clean energy investor and environmental activist Daniel Abbasi , Jerry Weintraub , Bach and Gelber .   Episodes explored the effects of rising sea levels , historic droughts and flooding , water scarcity , ocean acidification , deforestation and the rapidly increasing extinction rate of species , but also focused on `` solutions that individuals , communities , companies and even governments can use to address worldwide climate change '' , including cheaper solar and wind energy , advancing battery technology and electric cars . Hosts included Cameron , Schwarzenegger , Harrison Ford , Ian Somerhalder , America Ferrera , David Letterman , Gisele Bündchen , Jack Black , Matt Damon , Jessica Alba , Sigourney Weaver , and various other actors and journalists .   Schwarzenegger reflected on how the series tries to make the issue of climate change resonate with the public : `` I think the environmental movement only can be successful if we are simple and clear and make it a human story . We will tell human stories in this project . The scientists would never get the kind of attention that someone in show business gets . '' Cameron elaborated : `` We did n't use our celebrities as talking head experts , because they 're not climate experts . They were concerned , intelligent , curious citizens who were out to find answers . They were functioning as journalists . '' Newsweek said that the celebrity hosts `` lend sparks to an issue that sends most viewers for the exits '' .

Global warming <=SEP=> Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years .   In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing .   Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years .   Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) ,  whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change .   Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .