Sentences with phrase «volcanic influences increases»

Not exact matches

Their findings: natural influences such as changes in the amount of sunlight or volcanic eruptions did not explain the warming trends, but the results matched when increasing levels of greenhouse gas emissions were added to the mix.

These temperature increases can not be attributed easily to volcanic influences and are most probably solar in origin.»

The red line incorporates natural influences like changes in solar output and volcanic activity but virtually all of the long - term warming is attributable to human - caused increases in greenhouse gasses.

However, there is not compelling evidence that anthropogenic CO2 was sufficient to influence Earth's temperatures prior to 1950, i.e. «Climate model simulations that consider only natural solar variability and volcanic aerosols since 1750 — omitting observed increases in greenhouse gases — are able to fit the observations of global temperatures only up until about 1950.»

Neely (2013 http://onlinelibrary.wiley.com/doi/10.1002/grl.50263/abstract): «Comparison of the model results to observations reveals that moderate volcanic eruptions, rather than anthropogenic influences, are the primary source of the observed increases in stratospheric aerosol.»

92) If one factors in non-greenhouse influences such as El Nino events and large volcanic eruptions, lower atmosphere satellite - based temperature measurements show little, if any, global warming since 1979, a period over which atmospheric CO2 has increased by 55 ppm (17 per cent).

Forster et al. (2007) described four mechanisms by which volcanic forcing influences climate: RF due to aerosol — radiation interaction; differential (vertical or horizontal) heating, producing gradients and changes in circulation; interactions with other modes of circulation, such as El Niño - Southern Oscillation (ENSO); and ozone depletion with its effects on stratospheric heating, which depends on anthropogenic chlorine (stratospheric ozone would increase with a volcanic eruption under low - chlorine conditions).