NSF Org: |
OCE Division Of Ocean Sciences |
Recipient: |
|
Initial Amendment Date: | February 12, 2015 |
Latest Amendment Date: | January 17, 2017 |
Award Number: | 1458305 |
Award Instrument: | Continuing Grant |
Program Manager: |
Henrietta Edmonds
hedmonds@nsf.gov (703)292-7427 OCE Division Of Ocean Sciences GEO Directorate For Geosciences |
Start Date: | February 15, 2015 |
End Date: | January 31, 2019 (Estimated) |
Total Intended Award Amount: | $1,244,524.00 |
Total Awarded Amount to Date: | $1,244,524.00 |
Funds Obligated to Date: |
FY 2016 = $581,393.00 FY 2017 = $151,452.00 |
History of Investigator: |
|
Recipient Sponsored Research Office: |
266 WOODS HOLE RD WOODS HOLE MA US 02543-1535 (508)289-3542 |
Sponsor Congressional District: |
|
Primary Place of Performance: |
360 Woods Hole Road Woods Hole MA US 02543-0151 |
Primary Place of Performance Congressional District: |
|
Unique Entity Identifier (UEI): |
|
Parent UEI: |
|
NSF Program(s): |
Chemical Oceanography, ANS-Arctic Natural Sciences |
Primary Program Source: |
0100XXXXDB NSF RESEARCH & RELATED ACTIVIT |
Program Reference Code(s): |
|
Program Element Code(s): |
|
Award Agency Code: | 4900 |
Fund Agency Code: | 4900 |
Assistance Listing Number(s): | 47.050 |
ABSTRACT
In this project, investigators participating in the 2015 U.S. GEOTRACES Arctic expedition will measure radium and thorium isotopes in the western Arctic Ocean. In common with other national initiatives in the International GEOTRACES Program, the goals of the U.S. Arctic expedition are to identify processes and quantify fluxes that control the distributions of key trace elements and isotopes in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions. Some trace elements are essential to life, others are known biological toxins, and still others are important because they can be used as tracers of a variety of physical, chemical, and biological processes in the sea. The radionuclides to be measured as part of this project are important because they are oceanographic tracers that provide information on rates of cycling of other trace elements. The project will involve training opportunities for graduate student researchers and for undergraduate students from under-represented groups. Results from the study will be shared publicly through the Woods Hole Oceanographic Institution?s Center for Marine and Environmental Radioactivity.
While other GEOTRACES projects will map the distribution of numerous trace elements and their isotopes (TEIs), their distribution cannot be properly interpreted without concurrent measurement of tracers capable of providing rates of internal TEI cycling processes and fluxes at boundaries and across interfaces. The isotopes to be measured in this project include a suite of uranium/thorium series radionuclides, including the shorter-lived 234-Th and 228-Th as well as the radium quartet (224-Ra, 223-Ra, 228-Ra, 226-Ra). These tracers have the appropriate half-lives and reactivities to allow for study of horizontal and vertical transport and mixing, as well as removal at ocean boundaries, supply via rivers and submarine groundwater discharge, surface scavenging and export and subsurface remineralization. The researchers have considerable experience developing and implementing the most efficient methods to sample and quantify this suite of tracers, which includes use of battery powered in-situ pumps for large volume sampling. Hence, in addition to the proposed work on uranium/thorium series radionuclides, the team will also provide a service to other GEOTRACES researchers by coordinating pump use and sampling for many essential particulate TEIs.
PUBLICATIONS PRODUCED AS A RESULT OF THIS RESEARCH
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).
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
PROJECT OUTCOMES REPORT
Disclaimer
This Project Outcomes Report for the General Public is displayed verbatim as submitted by the Principal Investigator (PI) for this award. Any opinions, findings, and conclusions or recommendations expressed in this Report are those of the PI and do not necessarily reflect the views of the National Science Foundation; NSF has not approved or endorsed its content.
This NSF funded research project found surprising evidence of rapid climate change in the Arctic: In the middle of the Arctic Ocean near the North Pole, scientists discovered that the levels of radium-228 have almost doubled over the last decade.
The finding indicates that large-scale changes are happening along the coast?because the source of the radium is the land and shallow continental shelves surrounding the ocean. These coastal changes, in turn, could also be delivering more nutrients, carbon, and other chemicals into the Arctic Ocean and lead to dramatic impacts on Arctic food webs and animal populations.
The research team suspects that melting sea ice has left more open water near the coast for winds to create waves. The wave action reaches down to the shallow shelves and stirs up sediments, releasing radium that is carried to the surface and away into the open ocean. The same mechanism would likely also mobilize and deliver more nutrients, carbon, and other chemicals into the Arctic Ocean, fueling the growth of plankton at the bottom of the food chain. That, in turn, could have significant impacts on fish and marine mammals and change the Arctic ecosystem.
But there are other possible contributing factors that are causing changes over the shelf, the scientists say. More wave action can also cause more coastline erosion, adding more terrestrial sediment into the ocean. Warming temperatures can thaw permafrost, liberating more material into the ocean, and increasing river and groundwater runoff can carry more radium, nutrients, carbon, and other material into the Arctic.
The researchers contend that continued monitoring of shelf inputs to Arctic surface waters is vital to understand how the changing climate will affect the chemistry, biology, and economic resources of the Arctic Ocean.
-Lonny Lippsett, Lauren Kipp, and Matt Charette
Last Modified: 04/19/2019
Modified by: Matthew A Charette
Please report errors in award information by writing to: awardsearch@nsf.gov.