Query: A cold day in Chicago in winter has nothing to do with the trend of global warming.

Relevant passages:
Chicago <=SEP=> Chicago ( -LSB- ʃᵻˈkɑːɡoʊ -RSB- or -LSB- ʃᵻˈkɔːɡoʊ -RSB- ) , officially the City of Chicago , is the third-most populous city in the United States . With over 2.7 million residents , it is also the most populous city in both the state of Illinois and the Midwestern United States . It is the county seat of Cook County . The Chicago metropolitan area , often referred to as Chicagoland , has nearly 10 million people and is the third-largest in the U.S. Chicago has been called a global architecture capital . In terms of wealth and economy , Chicago is considered one of the most important business centers in the world .   Chicago was incorporated as a city in 1837 , near a portage between the Great Lakes and the Mississippi River watershed , and grew rapidly in the mid-nineteenth century . Positioned along Lake Michigan , the city is an international hub for finance , commerce , industry , technology , telecommunications , and transportation : O'Hare International Airport is the second-busiest airport in the world when measured by aircraft traffic ; the region also has the largest number of U.S. highways and rail road freight . In 2012 , Chicago was listed as an alpha global city by the Globalization and World Cities Research Network , and ranked seventh in the world in the 2016 Global Cities Index . Chicago has the third-largest gross metropolitan product in the United States -- about $ 640 billion according to 2015 estimates . The city has one of the world 's largest and most diversified economies with no single industry employing more than 14 % of the workforce .   In 2016 , Chicago hosted over 54 million domestic and international visitors , a new record making it one of the top visited cities in the nation . Landmarks in the city include Millennium Park , Navy Pier , the Magnificent Mile , Art Institute of Chicago , Museum Campus , the Willis ( Sears ) Tower , Museum of Science and Industry , and Lincoln Park Zoo . Chicago 's culture includes the visual arts , novels , film , theater , especially improvisational comedy , and music , particularly jazz , blues , soul , hip hop , gospel and house music . There are many colleges and universities in the Chicago area ; among these , Northwestern University , University of Chicago , and the University of Illinois at Chicago are classified as `` highest research '' doctoral universities . Additionally , Chicago has professional sports teams in each of the major professional leagues . The city has many nicknames , the best-known being the Windy City .

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 .

Climate change in the United States <=SEP=> Because of global warming , there has been concern in the United States and internationally , that the country should reduce total greenhouse gas which is relatively high per capita .   In 2012 , the United States experienced its warmest year on record . , the thirteen warmest years for the entire planet have all occurred since 1998 , transcending those from 1880 .   From 1950 to 2009 , the American government 's surface temperature record shows an increase by 1 F-change , approximately . Global warming has caused many changes in the U.S. . According to a 2009 statement by the National Oceanic and Atmospheric Administration ( NOAA ) , trends include lake and river ice melting earlier in the spring , plants blooming earlier , multiple animal species shifting their habitat ranges northward , and reductions in the size of glaciers .   Predicting future climate changes are fraught with difficulty . Some research has warned against possible problems due to American climate changes such as the spread of invasive species and possibilities of floods as well as droughts . Changes in climate in the regions of the United States appear significant . Drought conditions appear to be worsening in the southwest while improving in the northeast for example .   President Barack Obama committed in the December 2009 Copenhagen Climate Change Summit to reduce carbon dioxide emissions in the range of 17 % below 2005 levels by 2020 , 42 % below 2005 levels by 2030 , and 83 % below 2005 levels by 2050 . In an address towards the U.S. Congress in June 2013 , Obama detailed a specific action plan to achieve the 17 % carbon emissions cut from 2005 by 2020 . He included such measures as shifting from coal-based power generation to solar and natural gas production .   Climate change is seen as a national security threat to the United States .   In 2015 , according to The New York Times and others , oil companies knew that burning oil and gas could cause global warming since the 1970s but , nonetheless , funded deniers for years .   2016 was an historic year for billion-dollar weather and climate disasters in U.S.