The viability of oxygen isotope analysis of tooth enamel by UV laser ablation and fluorination has been demonstrated by comparison with the Ag PO extraction method. In-situ analyses by UV laser fluorination using both isotope ratio mass 3 4 Ž . spectrometry and isotope ratio monitoring gas chromatography mass spectrometry irm-GCMS microanalysis are comparaŽ . 18 ble to those of the Ag PO method...

[1] In the last 25 years of the 20th century most major land regions experienced a summer warming trend, but the central U.S. cooled by 0.2–0.8 K. In contrast most climate projections using GCMs show warming for all continental interiors including North America. We examined this discrepancy by using a regional climate model and found a circulation-precipitation coupling under enhanced greenhous...

The large spread of the response to anthropogenic forcing simulated by state-of-the-art climate models in the Arctic is investigated. A feedback analysis framework specific to the Arctic is developed to address this issue. The feedback analysis shows that a large part of the spread of Arctic climate change is explained by the longwave feedback parameter. The large spread of the negative longwav...

An important step toward improving radiative transfer codes in general circulation models (GCMs) is to thoroughly evaluate them either by comparison to measurements directly or by comparing them to other data-validated radiation models. The Rapid Radiative Transfer Model (RRTM) shortwave (SW) radiation model accurately reproduces direct beam fluxes from the Line-by-Line Radiative Transfer Model...

Many general circulation models (GCMs) share similar biases in the representation of the intertropical convergence zone (ITCZ) in the Atlantic, even when they are forced with the time series of the observed sea surface temperature (SST). Specifically, they overestimate precipitation in the Southern Hemisphere in boreal spring and in the Caribbean region in boreal summer. The majority of the mod...

[1] Several state‐of‐the‐art general circulation models (GCMs) predict that large volcanic eruptions should result in anomalous dry conditions throughout much of monsoon Asia. Here, we use long and well‐validated proxy reconstructions of Asian droughts and pluvials to detect the influence of volcanic radiative forcing on the hydroclimate of the region since the late Medieval period. Superposed ...

Scaling aspects of river flow routing are studied by comparing two flow routing schemes, one designed for use in coupled general circulation models (GCMs) and operated at large spatial scales (3⁄4350 km), and the other designed for use in typical hydrological applications at small spatial scales (3⁄425 km). The same runoff data are used as input into the two routing schemes, and comparisons are...