And while 66.4% of the abstracts expressed no position on the anthropogenic factor, 32.6% endorsed it. Less than 1% of the research papers they reviewed rejected the idea of human influence on our climate. Led by John Cook, a researcher with the Climate Change Communication Research Hub at Australia's Monash University, American, British and Canadian researchers examined 11,944 climate abstracts published in peer-reviewed scientific literature between 19. "But the one thing pretty much every scientist agrees upon today is that the warming we're seeing is driven by burning fossil fuels." Why did it take a while to reach this conclusion?Ī widely discussed analysis of the evolution of the scientific consensus on anthropogenic global warming was published in 2013. "There are uncertainties and nuances to discuss in climate science," said Cook. He said the scientific community is as confident in human-caused climate change today as in the understanding of the theory of gravity. "Only the greenhouse gas emissions from fossil fuels and industrialization gave us a prediction that lines up with the warming we're seeing," Cook told DW. The last time CO2 levels were so elevated was some 3 million years ago, when sea levels were around 30 meters (100 feet) higher and modern humans didn't even exist.īenjamin Cook, a climate scientist at the NASA Goddard Institute for Space Studies, said back in the late 20th century, when researchers started to look for answers to explain the warming trend, they examined different factors including greenhouse gases, solar energy, ocean circulation and volcanic activity. In May 2021, the average global level of atmospheric CO2 hit 415 ppm. It has attributed atmospheric CO2 increase to anthropogenic (human-caused) emissions, with three-quarters of them coming from fossil fuel burning, and the rest from land use change. By 1999, it had risen to 367 ppm, the IPCC said.Įstablished as a UN body in 1988, the IPCC has 195 member countries and assesses the science related to climate change. In 2001, the Intergovernmental Panel on Climate Change (IPCC) estimated that the concentration of CO2 in the atmosphere had been 280 parts per million (ppm) for several thousand years before the industrial era. The report described increasing levels of greenhouse gases in the atmosphere resulting from human activities, as "a major driver of climate change". This refers to the period between 1850-1900, when fossil fuels were not widely used as a means of creating energy. But this started changing when humans began burning fossil fuels as a global means of creating energy - resulting in a sharp rise of unnatural CO2 emissions. This has interfered with the planet's atmospheric balance.Īnd, as a result, Earth started warming faster.Īccording to the WMO's State of the Global Climate 2020 report, the average temperature last year was 1.2 degrees Celsius (2.2 Fahrenheit) higher than pre-industrial levels. Without the greenhouse gas effect, surface temperatures would drop 33 degrees Celsius (59.4 degrees Fahrenheit), according to the World Meteorological Organization (WMO) - making the planet a frozen, uninhabitable place.įor thousands of years, nature had well-regulated the concentration of these gases. The natural heat-trapping gases in our atmosphere, which include carbon dioxide (CO2), methane and nitrous oxide, are necessary to keep the Earth's surface temperature warm. It happens when certain gases in our atmosphere trap the heat emitted from Earth and act as the planet's very own greenhouse. The greenhouse effect - a natural process that warms the Earth - is necessary to sustain life on the planet. What do CO2 emissions have to do with climate change? ![]() The study also revealed that for the last 2,000 years Earth has actually been in a natural cooling period in terms of its position relative to the sun.īut this natural cooling has gone unregistered due to unprecedented warming caused by human emissions of greenhouse gases, the paper explains. The conclusion was the same: our planet has warmed faster in the past century than at any time since the end of the last ice age. In 2013, research published in the journal Science analyzed even earlier temperatures, dating back 11,000 years. The outcome illustrated little variation for many hundreds of years until the 20th century, when there was suddenly a sharp rise. To work out earlier temperatures going back half a millennium before the thermometer was invented, they studied so-called proxy or natural records - measurements of ice cores, tree rings and corals. In 1998, researchers from the US University of Massachusetts Amherst and the Laboratory of Tree-Ring Research at the University of Arizona published a study showing the average annual global temperature over the past 1,000 years.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |