Sentences with phrase «human greenhouse gas emissions began»

This year's temperatures now appear set to exceed 1998's values by around 0.35 C — or about one - third of the entire warming total seen since large - scale human greenhouse gas emissions began during the late 19th century.

The emissions scenarios included business as usual (BAU) and three other scenarios (B, C, D) in which global human greenhouse gas emissions began slowing in the year 2000.

Not exact matches

Scientists can confidently say that Earth is warming due to greenhouse gas emissions caused by humans, but data on climate trends over the Antarctic and the surrounding Southern Ocean only go back to 1979 when regular satellite observations began.

Some experts claim the rise in temperature during the past century was «unprecedented» and proof that immediate action to reduce human greenhouse gas emissions must begin.

Beginning in the late 1960s, computer simulations indicated possible changes in temperature and precipitation that could occur due to human - induced emission of greenhouse gasses into the atmosphere.

First, while the early 20th century warming was likely predominantly naturally - caused (i.e. low volcanic activity and increasing solar activity), there was also a significant human contribution as greenhouse gas emissions began to ramp up.

Given that for over 20 years since international climate change negotiations began, the United States has refused to commit to reduce its greenhouse gas emissions based upon the justification that there is too much scientific uncertainty to warrant action, if it turns out that human - induced climate change actually greatly harms the health and ecological systems on which life depends of others, should the United States be responsible for the harms that could have been avoided if preventative action had been taken earlier?

Emissions of several important greenhouse gases that result from human activity have increased substantially since large - scale industrialization began in the mid-1800s.

That finding struck Smith, a Republican from Texas who maintains that human - caused emissions of greenhouse gases are not causing global warming, as suspicious, and he began a dogged effort to determine if the scientists had manipulated data to arrive at politically - motivated results.