Research

Currently Funded Projects

Dr. Wanamaker is working on the following research projects:

  • NSF, “Collaborative research: Bridging the gap from northern Iberia to northwest Africa to reconstruct atmospheric dynamics and hydroclimate for the last 2,500 years” (PI, start date- 01 July 2018, end date- 30 June 2021).
  • Maine Sea Grant, “From Paleoceanography to Policy: applying historical coastal pH baselines from long-lived shells and skeletons to contemporary shellfish aquaculture”(Co-PI, start date- 01 July 2018, end date- 30 June 2020); PI Michele Lavigne (Bowdoin College).
  • NSF, “Collaborative Research: Multi-proxy reconstructions of North Pacific decadal variability from bivalve mollusks and trees”(Co-PI, start date- 15 May 2017, end date- 14 May 2020); PI Bryan Black (University of Texas- Austin).
  • Center for Global and Regional Environmental Research (University of Iowa), “Development of a proxy record of El Niño/Southern Oscillation (ENSO) from Colombian Stalagmites during the last 6,000 years” Role: PI, July 1, 2019 – June 30, 2020.

 

 


Current Research: Gulf of Maine. Nina Whitney, PhD student.

This project seeks to reconstruct hydrographic dynamics in the Gulf of Maine over the last several centuries in order to assess recent warming in the Gulf of Maine and better predict future changes to the region. This work utilizes the marine bivalve proxy Arctica islandica (ocean quahog), shells of which grow in annual increments, providing annually resolved data. Increment widths and oxygen isotopes measured in these shells correspond well to nearby sea surface temperature instrumental records and indicate significant oscillations in seawater temperatures in the region over the last 250 years.

Part of the impetus for researching hydrographic dynamics in the Gulf of Maine is recent modeling work that suggest that the Gulf of Maine has a strong inverse relationship to the strength of the Atlantic Meridional Overturning Circulation (AMOC) due to the influence that AMOC strength has on the path of the Gulf Stream. By reconstructing Gulf of Maine seawater temperatures, we hope to gain a better understanding of how AMOC strength has changed over the last several centuries.


 


Current Project: Understanding past precipitation dynamics of Iberian Peninsula. Diana Thatcher, PhD student.

This project uses stalagmites from a cave in central Portugal, Buraca Glorioso, to study the climate of the last 2500 years, specifically looking at the hydroclimate of central Portugal and the North Atlantic Oscillation. Changes in hydroclimate (from wetter to drier or drier to wetter) are heavily dependent on the North Atlantic Oscillation (NAO), the predominant mode of atmospheric variability in the North Atlantic region. Note the negative correlation with Portugal winter precipitation and the wNAO (winter NAO) index as shown in the figure (i.e. high wNAO index = low precipitation for Portugal). Combining oxygen isotope measurements with uranium-thorium dates from stalagmites will allow us to better understand of the magnitude and timing of decadal-scale changes in hydroclimate.