Kristine DeLong
Professor Louisiana State University
- Baton Rouge LA
Dr. DeLong has expertise in paleoceanography and paleoclimatology, especially in tropical regions with 19 years of research experience.
Biography
Dr. DeLong’s research is focused on climate change of the past primarily in the subtropics to tropical regions for the past 130,000 years. Current projects include investigating shifts in sea surface temperature and ocean circulation in the Gulf of Mexico and the Caribbean Sea using the chemical variations in the skeletons of large boulder size corals, which can live for many centuries.
Areas of Expertise
Research Focus
Tropical Paleoceanography & Coral Paleoclimatology
Dr. DeLong’s research focuses on tropical paleoceanography and paleoclimatology, reconstructing past sea-surface temperatures, ocean circulation, and coral-reef responses in the Gulf of Mexico, Caribbean, and Pacific. She integrates centuries-old coral-core drilling, geochemical proxies and U-Th dating with climate-model comparisons to trace climate variability and refine coastal-resilience forecasts.
Education
University of South Florida
Ph.D.
Marine Science
2008
University of South Florida
M.S.
Marine Science
2006
University of South Florida
B.S.
Mechanical Engineering
1991
Accomplishments
Geophysical Research Letters Outstanding Reviewer Award
2020
Paleoceanography and Paleoclimatology Outstanding Reviewer Award
2019
LSU Alumni Association Faculty Excellence Award
2017
Media Appearances
‘Underwater forests’ lying preserved at the bottom of the Gulf of Mexico push LSU research forward
LSU Reveille online
2024-07-22
Kristine L. DeLong, a paleoclimatologist and LSU geography and anthropology professor, has been working on these sites since 2012. She said the last decade has been productive for her research.
Underwater forest found off Alabama prompts study into ‘sudden’ event that buried it
Sun Herald online
2021-06-07
“We also have evidence from tree-ring analysis that suggests a ‘sudden’ event, occurring within years, resulted in several trees dying at the same time,” Associate Professor Kristine DeLong of Louisiana State University told McClatchy News.
Gulf of Mexico coral reefs to protect from storm surge in the future—But will they?
Phys.org online
2019-12-05
While researchers have done a lot of work on the Great Barrier Reef in Australia and in the Pacific and Caribbean reefs, DeLong and her team are among the first to produce climate projections specifically for the Gulf of Mexico.
Articles
New and old coral radiocarbon records revisited for the subtropical and tropical Atlantic Ocean
Radiocarbon2025
Ocean radiocarbon (14C) is a proxy for air-sea exchange, vertical and horizontal mixing, and water mass identification. Here, we present five pre- to post-bomb coral Δ14C records from West Flower Garden Bank and Santiaguillo reefs in the Gulf of Mexico, Boca de Medio, and Isla Tortuga near the Cariaco Basin north of Venezuela. To assess basin-wide Δ14C variability, we compiled the Atlantic Ocean reef-building surface coral Δ14C records (24 corals and 28 data sets in total) with these new records. Cumulatively, the Δ14C records, on their independent age models, reveal the onset of post-bomb Δ14C trends in 1958 ±1 to 2 years. A general decrease in maximum Δ14C values occurs with decreasing latitude reflecting the balance between air-sea gas exchange and surface water residence time, vertical mixing, and horizontal advection.
Rapid decline and mortality of a Pleistocene-aged forest now submerged in the northern Gulf of Mexico, USA
npj Climate and Atmospheric Science2025
The Gulf and Atlantic Coastal Plains of the southern United States are characterized by a wide continental shelf that was subaerially exposed for ca. 80,000 years during glacial-interval marine regressions and transgressions. Given their present submergence, little is known about the vegetation dynamics, particularly at annual time scales, of these formerly terrestrial sites due to erosional processes associated with marine transgressions. Here, we present an annually resolved and well-replicated 489-year tree-ring chronology from macrobotanical specimens—anatomically identified as Taxodium distichum (L.) Rich.—collected in situ from a recently exposed submerged forest in 18 m water depth in the northern Gulf of Mexico. This chronology not only reveals historical vegetation dynamics at annual resolutions during Marine Isotope Stages 3–5a, but it also captures a catastrophic mortality event likely connected to intense storm activity, perhaps driven by freshwater fluxes from Heinrich events. Our findings are supported by coupled climate model simulations from the last glaciation, providing new insights into the environmental history of the southeastern US coastal regions.
Storm-driven tree exposure and geomorphic change: predicting the distribution of preserved Late Pleistocene tree stumps on the outer Alabama continental shelf
Marine Geology2024
The Alabama Underwater or Drowned Forest is a well-preserved Late Pleistocene (dated to 72–56 ± 8 ka, 2σ) terrestrial landform on the northern Gulf of Mexico continental shelf that provides geomorphic and ecosystem information rarely preserved during the glacial intervals. Stumps of bald cypress (Taxodium distichum (L.) Rich.) trees were exposed in ∼18 m of water following Hurricane Ivan in 2004. This research investigates geomorphic changes to the Mississippi-Alabama-Florida (MAFLA) sand sheet, which presents as shore-oblique Holocene sand ridges, and the exposure and burial of tree stumps following the passage of Hurricane Sally in 2020 using repeat sidescan and bathymetric surveys (2015–2016 and 2021). Using two newly identified tree exposure areas and their geological properties, this research also hypothesized a new location where tree stumps may be outcropping. T
Snapshots of coastal ecology using multiproxy analysis reveals insights into the preservation of swamp and marsh environments since the late Pleistocene
Geochemistry, Geophysics, Geosystems2024
The southeastern United States Coastal Plain ecosystem contains baldcypress (Taxodium distichum) swamps and grass‐dominated marshes. These ecosystems also occurred on the exposed continental shelf during lower sea levels but are rarely preserved due to the mechanically erosive nature of transgression and regression. Two presently marine sites on the northeastern Gulf of Mexico's continental shelf contain well‐preserved woody terrestrial sediments that were the subject of previous studies. This study continues the investigation using geochemical (δ13C, δ15N, δ34S) and palynological characteristics of these formerly terrestrial sediments to determine if swamps and/or marshes existed at the time of deposition.
17O‐Excess in Tropical Cyclones Reflects Local Rain Re‐Evaporation More Than Moisture Source Conditions
Journal of Geophysical Research: Atmospheres2024
17O‐excess is a relatively new water isotope parameter that could potentially provide useful information about the hydrological cycle. Previous works focusing on 17O‐excess in polar regions suggest that it primarily tracks moisture source relative humidity, but little is known about how to interpret 17O‐excess data in lower latitudes. Here we present quasi‐hourly triple oxygen isotope data of precipitation collected from two tropical cyclones in Texas and Louisiana in 2020 to understand the impacts of environmental and meteorological processes on the 17O‐excess of low‐to mid‐latitude precipitation. We find that at both hourly timescales and the event scale, 17O‐excess is strongly correlated to changes in on‐site rainfall intensity and relative humidity, which is consistent with the theory that the isotopic fractionation associated with rain re‐evaporation lowers the 17O‐excess of the remaining droplet.
Affiliations
- American Geophysical Union (AGU)
- American Academy of Underwater Sciences (AAUS)
- Earth Science Woman’s Network (ESWN)
- Association of America Geographers (AAG)
- National Association of Geoscience Teachers (NAGT)
- Geochemical Society
- International Society for Reef Studies (ISRS)
- Sigma Xi
Event Appearances
The Underwater Ancient Forest
2019 | Science Café LSU
Research Grants
Coastal indigenous fisheries assessment (CIFA) using archaeological and ecologic perspectives
U.S. Geological Survey, South Central Climate Adaptation Science Center, University of Oklahoma,
2023-2026
Developing a Diverse Research Workforce with Expertise in Hydrological Climate Events in the Upland Watersheds of the Northern Gulf of Mexico,”
U.S. Geological Survey, National Climate Adaptation Science Center and Regional Climate Adaptation Science Centers, Climate Adaptation Scientists of Tomorrow Program Undergraduate Research Experience
2022-2024
Media
