skip to main content

Attention:

The NSF Public Access Repository (NSF-PAR) system and access will be unavailable from 11:00 PM ET on Friday, May 17 until 8:00 AM ET on Saturday, May 18 due to maintenance. We apologize for the inconvenience.


Search for: All records

Award ID contains: 1566432

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. Abstract

    During the last deglaciation Earth’s climate experienced strong and abrupt variations, resulting in major changes in global temperature, sea level, and ocean circulation. Although proxy records have significantly improved our understanding of climate during this period, questions remain regarding the connection between ocean circulation evolution and resulting geotracer distributions, including those of deep waters in the Pacific. Here we use the C‐iTRACE simulation, a transient ocean‐only, isotope‐enabled version of the Community Earth System Model, to better understand deglacial deep Pacific radiocarbon evolution in the context of circulation and reservoir age changes. Throughout the deglaciation, the Pacific Ocean circulation in C‐iTRACE responds strongly to glacial meltwater forcing, leading to large changes in deep Pacific Δ14C age. A multi‐millennial weakening of the overturning circulation from 20 to 15 ka BP leads to increases in deep Pacific Δ14C ages, but from 20 to 18 ka BP, nearly half (40%–60%) of this aging is controlled by changing surface reservoir age, corroborating previous studies showing that Δ14C is not solely a circulation age tracer. As the deglaciation proceeds, circulation change controls progressively more of the Δ14C age, accounting for more than 75% of it across the deep Pacific from 15 to 8 ka BP.

     
    more » « less