Carbon pollution up to 2 million pounds a second Associated Press Copyright 2012 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Updated 10:23 a.m., Sunday, December 2, 2012 [...] scientists say it's now unlikely that global warming can be limited to a couple degrees, which is an international goal. Of the planet's top 10 polluters, the United States and Germany were the only countries that reduced their carbon dioxide emissions. Last year, all the world's nations combined pumped nearly 38.2 billion tons of carbon dioxide into the air from the burning of fossil fuels such as coal and oil, according to new international calculations on global emissions published Sunday in the journal Nature Climate Change. The total amounts to more than 2.4 million pounds of carbon dioxide released into the air every second. Because emissions of the key greenhouse gas have been rising steadily and most carbon stays in the air for a century, it is not just unlikely but "rather optimistic" to think that the world can limit future temperature increases to 2 degrees, said the study's lead author, Glen Peters at the Center for International Climate and Environmental Research in Oslo, Norway. In 1997, most of the world agreed to an international treaty, known as the Kyoto Protocol, that required developed countries such as the United States to reduce greenhouse gas emissions by about 5 percent when compared with the baseline year of 1990. The latest pollution numbers, calculated by the Global Carbon Project, a joint venture of the Energy Department and the Norwegian Research Council, show that worldwide carbon dioxide levels are 54 percent higher than the 1990 baseline.