Details

Autor(en) / Beteiligte

• Rutherford, S.
• Mann, M. E.
• Delworth, T. L.
• Stouffer, R. J.

Titel

Climate Field Reconstruction under Stationary and Nonstationary Forcing

Ist Teil von

• Journal of climate, 2003-02, Vol.16 (3), p.462-479

Ort / Verlag

Boston, MA: American Meteorological Society

Erscheinungsjahr

2003

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• The fidelity of climate reconstructions employing covariance-based calibration techniques is tested with varying levels of sparseness of available data during intervals of relatively constant (stationary) and increasing (nonstationary) forcing. These tests employ a regularized expectation-maximization algorithm using surface temperature data from both the instrumental record and coupled ocean–atmosphere model integrations. The results indicate that if radiative forcing is relatively constant over a data-rich calibration period and increases over a data-sparse reconstruction period, the imputed temperatures in the reconstruction period may be biased and may underestimate the true temperature trend. However, if radiative forcing is stationary over a data-sparse reconstruction period and increases over a data-rich calibration period, the imputed values in the reconstruction period are nearly unbiased. These results indicate that using the data-rich part of the twentieth-century instrumental record (which contains an increasing temperature trend plausibly associated with increasing radiative forcing) for calibration does not significantly bias reconstructions of prior climate.