Query: Seventeen of the 18 warmest years have occurred since 2000.

Relevant passages:
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.

Constanța <=SEP=> Constanța ( -LSB- konˈstant͡sa -RSB- ) , historically known as Tomis ( Κωνστάντζα or Κωνστάντια , Konstantia , Кюстенджа or Констанца , Köstence ) , is the oldest continuously inhabited city in Romania . It was founded around 600 BC . The city is located in the Dobruja region of Romania , on the Black Sea coast . It is the capital of Constanța County and the largest city in the region .   As of the 2011 census , Constanța has a population of 283,872 , making it the fifth most populous city in Romania . The Constanța metropolitan area includes 14 localities within 30 km of the city , and , with 425,916 inhabitants , it is the second largest metropolitan area in Romania .   The Port of Constanța has an area of 39.26 km2 and a length of about 30 km . It is the largest port on the Black Sea , and one of the largest ports in Europe .

Instrumental temperature record <=SEP=> The instrumental temperature record provides the temperature of Earth 's climate system from the historical network of in situ measurements of surface air temperatures and ocean surface temperatures . Data are collected at thousands of meteorological stations , buoys and ships around the globe . The longest-running temperature record is the Central England temperature data series , that starts in 1659 . The longest-running quasi-global record starts in 1850 . In recent decades more extensive sampling of ocean temperatures at various depths have begun allowing estimates of ocean heat content but these do not form part of the global surface temperature datasets .

2006 European heat wave <=SEP=> The 2006 European heat wave was a period of exceptionally hot weather that arrived at the end of June 2006 in certain European countries . The United Kingdom , France , Belgium , the Netherlands , Luxembourg , Italy , Poland , the Czech Republic , Hungary , Germany and western parts of Russia were most affected . Several records were broken . In the Netherlands , Belgium , Germany , Ireland and the United Kingdom , July 2006 was the warmest month since official measurements began .