A new study has concluded that methane emissions from the U.S. oil and natural gas supply chain in 2015 amounted to about 2.3% of gross U.S. gas production. Emissions of this magnitude significantly increase the GHG footprint of natural gas power generation and erode the carbon advantage of natural gas over coal.
There is strong evidence of marked changes in temperature extremes across the contiguous United States – extreme cold waves have become less common while extreme heat waves have become more common and heavy precipitation events in most parts of the United States have increased in both intensity and frequency. That is the conclusion of a report prepared by scientists from NOAA, NASA and other agencies.
In 1997 Raymo was the first to provide observations supporting the orbital forcing hypothesis for glacial/deglacial cycles that did not rely on orbital tuning. The research also suggested that ice sheet dynamics needed to be considered in addition to orbital forcing to explain the observed 100,000 year glacial/deglacial cycles.
A recent study has created a simple mathematical rule that can account for the timing of the onset of interglacials following ice ages over the past three million years. The rule is based on predictable long-term astronomical variations in the Earth’s orbit and tilt called Milankovitch cycles.