1932

Abstract

Abstract

To assess the significance of modern climate change, it is essential to place recent observed changes in a longer-term context. This review assesses the evidence from both “proxy” climate data and theoretical climate model simulations with regard to the nature and causes of climate variability over a time interval spanning roughly the past two millennia. Evidence is reviewed for changes in temperature, drought, and atmospheric circulation over this timescale. Methods for reconstructing past climate from proxy data are reviewed and comparisons with the results of climate modeling studies are provided. The assessment provided affirms the role of natural (solar and volcanic) radiative forcing in past changes in large-scale mean temperature changes and in dynamical modes of climate variability such as the North Atlantic Oscillation (NAO) and El Niño/Southern Oscillation (ENSO) influencing large-scale climate. At hemispheric scales, late twentieth century warmth appears unprecedented in the context of at least the past 2000 years. This anomalous warmth can only be explained by modern anthropogenic forcing.

Loading

Article metrics loading...

/content/journals/10.1146/annurev.earth.35.031306.140042
2007-05-30
2024-03-29
Loading full text...

Full text loading...

/content/journals/10.1146/annurev.earth.35.031306.140042
Loading
/content/journals/10.1146/annurev.earth.35.031306.140042
Loading

Data & Media loading...

  • Article Type: Review Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error