Comparison of observed and simulated tropical climate trends using a forward model of coral δ18O

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Global Change: Climate Variability (1635, 3305, 3309, 4215, 4513), Global Change: Global Climate Models (3337, 4928), Oceanography: General: Analytical Modeling And Laboratory Experiments, Paleoceanography: Corals (4220), Paleoceanography: El Nino (4522)

Scientific paper

The response of the tropical Pacific Ocean to future climate change remains highly uncertain, in part because of the disagreement among observations and coupled general circulation models (CGCMs) regarding 20th-century trends. Here we use forward models of climate proxies to compare CGCM simulations and proxy observations to address 20th-century trends and assess remaining uncertainties in both proxies and models. We model coral oxygen isotopic composition (δ18O) in a 23-site Indo-Pacific network as a linear function of sea-surface temperature (SST) and sea-surface salinity (SSS) obtained from historical marine observations (instrumental data) and a multimodel ensemble of 20th-century CGCM output. When driven with instrumental data from 1958 to 1990, the forward modeled corals (pseudocorals) capture the spatial pattern and temporal evolution of the El Niño-Southern Oscillation (ENSO). Comparison of the linear trend observed in corals and instrumental pseudocorals suggests that the trend in corals between 1958 and 1990 results from both warming (60%) and freshening (40%). From 1890 to 1990, the warming/freshening trend in CGCM pseudocorals is weaker than that observed in corals. Corals display a moderate trend towards a reduced zonal SST gradient and decreased ENSO-related variance between 1895 and 1985, whereas CGCM pseudocorals display a range of trend patterns and an increase in ENSO-related variance over the same period. Differences between corals and CGCM pseudocorals may arise from uncertainties in the linear bivariate coral model, uncertainties in the way corals record climate, undersensitivity of CGCMs to radiative forcing during the 20th century, and/or biases in the simulated CGCM SSS fields.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Comparison of observed and simulated tropical climate trends using a forward model of coral δ18O does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Comparison of observed and simulated tropical climate trends using a forward model of coral δ18O, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Comparison of observed and simulated tropical climate trends using a forward model of coral δ18O will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-994619

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.