In September this year, the United States exported more crude oil and petroleum products in a single month than imports, becoming the first net oil exporter in 70 years. Data shows that in September this year, the United States ’oil exports rose by 18% year-on-year, with an average daily rate of approximately 8.76 million barrels; oil imports fell by 12% year-on-year, with an average daily value of approximately 8.67 million barrels, a surplus of nearly 90,000 barrels. According to Kyodo News, this is the first time that the United States has achieved a one-month oil trade surplus since it began to aggregate oil import and export figures in 1949 and has become a net oil exporter. The U.S. Energy Information Administration released a short-term outlook for energy earlier in November. It is expected that the United States will maintain a deficit in oil trade throughout 2019, with an average daily deficit of 520,000 barrels. barrel. CNN reported in September 2018 that the United States has become the world's largest oil producer according to estimates by the US Department of Energy. According to the weekly oil supply and demand report released by the U.S. Energy Information Administration on November 27 this year, the current average daily oil production in the United States is approximately 12.9 million barrels. This figure is much higher than the current stage of oil production in Saudi Arabia and Russia. The monthly report released by the International Energy Agency in September this year shows that in June this year, the United States surpassed Saudi Arabia and became the world's largest crude oil exporter. The US media reported late last year that the United States was once a net exporter of crude oil, breaking its continued dependence on imported crude oil for more than 70 years. However, the report did not say how long the surplus lasted. In the past decade, the rise of shale oil in the United States has more than doubled its oil output, thereby changing the global energy landscape. However, the development of shale oil comes with environmental costs. Researchers have reminded that the amount of water and waste water produced by shale oil and gas extraction in the United States has increased significantly since 2011, indicating that the hydraulic fracturing method has a more significant impact on local water resources.