Climate change in the United States

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 and is the second largest in the world after China, as of 2014. 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 and is the second largest in the world after China, as of 2014. In 2012, the United States experienced its warmest year on record. As of 2012, 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 (0.56 °C), 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. 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 a historic year for billion-dollar weather and climate disasters in U.S. The United States was the second top emitter in terms of CO2 from fossil fuels in 2009. It produced 5,420 million metric tons (abbreviated as mt) of the substance, constituting 17.8% of the world's total at the time. The nation was also the second highest emitter in terms of all greenhouse gas emissions, including construction and deforestation-related changes, in 2005. Specifically, the U.S. produced 6,930 mt (15.7% of the world's total). In the cumulative emissions between 1850 and 2007, the U.S. was at the top in terms of all world nations, involved with 28.8% of the world's total. China's emissions have outpaced the U.S. in CO2 from 2006 onward. The U.S. produced 5.8 billion metric tons of CO2 in 2006, compared to the 6.23 billion coming from China. Per capita emission figures of China are about one quarter of those of the U.S. population.