Sentences with phrase «observations over the last century»

There's a historic trend in that direction based on observations over the last century or more.

Not exact matches

The key observation here is the increase in ocean heat content over the last half century (the figure below shows three estimates of the changes since 1955).

There's a lot in there, but, the authors write, the compilation of peer - reviewed scientific observations and models together «tell an unambiguous story: the planet is warming, and over the last half century, this warming has been driven primarily by human activity.»

Florida State University's James Elsner said ground data show every decade has been warmer than the last since the middle of the 20th century and satellite data - based observations «show continued warming over the past several decades.»

Overall the model means stick like glue to the observations, giving an impression of near - perfect understanding not just of global but of regional climate change over the last century.

The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of this unknown amplifying mechanism.The cosmic ray - ionization mechanism is too weak to influence global concentrations of CCN or their change over the last century or during a solar cycle in any climatically significant way.

That panel's first assessment report in 1990 concluded that «the size of the warming over the last century is... of the same magnitude as natural climate variability» and that «the unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more.»

Principally, there is paleo - climate data from previous quasi-equilibria like the Last Glacial Maximum or Eocene; evidence from the instrumental trends since the 19th Century; and climatological observations that correlate to longer term responses (either in the mean, seasonally or over interannual variations).