About

Kim Cobb is a climate scientist who serves as the Director of the Institute at Brown for Environment and Society. She is also a Professor of Environment and Society and Earth, Environmental, and Planetary Sciences. Her work addresses challenging problems that extend beyond college campuses, emphasizing the need for collaborative efforts that are quick and effective to achieve impactful solutions at a large scale.

Research topics

• Environmental science
• Oceanography
• Geology
• Climatology
• Political Science
• Environmental economics
• Engineering
• Seismology
• Environmental planning
• Natural resource economics
• Business
• Economics
• Environmental resource management
• Mathematics
• Meteorology
• Statistics
• Geography

Selected publications

• A TALE OF TWO PHILIPPINES SPELEOTHEM RECORDS: THE RELATIONSHIP BETWEEN SOUTHEAST ASIAN SUMMER AND WINTER MONSOON SYSTEMS DURING THE LATE HOLOCENE

  Abstracts with programs - Geological Society of America · 2025-01-01

  article
  PublisherDOI

• The PAGES CoralHydro2k Seawater δ ¹⁸ O Database: A FAIR-aligned compilation of seawater δ ¹⁸ O data to uncover 'hidden' insights from the global ocean

  2025-08-27

  articleOpen accessSenior author

  Abstract. The stable isotope values of seawater (δ18O and δ2H) provide valuable information on the exchange of water between the ocean, atmosphere, and cryosphere and on ocean mixing processes. As such, observational seawater δ18O and δ2H data place powerful constraints on hydrologic changes in the modern ocean. Seawater δ18O data are also essential for calibrating paleoclimate proxies based on the δ18O of marine carbonates and are an increasingly critical diagnostic tool for assessing model performance and skill in isotope-enabled global climate models. Despite their broad value, no centralized and actively-curated database for this type of data exists, even though a growing number of new seawater δ18O datasets have been generated over the last decade. As such, many seawater δ18O datasets remain ‘hidden’. To improve the accessibility of seawater δ18O data for the Earth Science research community, the Past Global Changes (PAGES) CoralHydro2k project has created a new, machine-readable, and metadata-rich database of observational seawater δ18O data, paired with seawater δ2H and salinity data, that is compliant with findability, accessibility, interoperability, and reusability (FAIR) standards for digital assets. The data has been collected from public databases and repositories, direct researcher data submissions, scientific papers, and student theses. In total, the PAGES CoralHydro2k Seawater δ18O Database contains over 18,600 data points with extensive metadata that makes the database suitable for a myriad of research applications. For hidden data, we searched for and included all datasets within the global ocean. For public data, our data collation efforts were focused on the upper 50 m from 35° N to 35° S (to aid in CoralHydro2k’s seawater δ18O reconstruction studies using δ18O and Sr/Ca in tropical-subtropical coral skeletons). We also provide a set of best practices to the community for reporting seawater isotope data in the future.

  PublisherOA PDFDOI

• Water Isotopologue Time Series across Tropical Sites during ENSO extremes

  2025-03-15

  preprintOpen access

  Potential anthropogenic shifts in the hydroclimate impacts of El Niño Southern Oscillation (ENSO) extremes are poorly resolved by available data. Water isotopologues provide valuable tracers of hydroclimatic processes, including the balance of precipitation versus evaporation and the relative importance of regional versus local drivers of hydroclimate variability  (Dee et al., 2023 and references therein; Moerman et al., 2013). However, very few water isotopologue datasets exist in the tropical Pacific, and those that do fail to resolve a full ENSO cycle. In this study, we present oxygen isotope (δ18O) and deuterium (δ2H) time series for precipitation, seawater, as well as sea-surface salinity time series from 5 sites spanning the tropical Pacific across the 2023/24 El Niño event and 2024/25 La Nina event.. Weekly seawater and daily rainwater δ18O time series from the Galapagos, Fiji, Hawaii, and Kiritimati Island, as well as rainwater δ18O time series from northern Borneo and Costa Rica reveal a distinct signature of the 2023/24 El Niño event. Preliminary analyses indicate that seawater δ18O values reflect both local and remote processes, with the relative balance being largely site-dependent. This study provides quantitative estimates of rainfall and seawater δ18O anomalies through a cycle of ENSO extremes, and investigates regional drivers of hydrologic circulation across space and time. Taken together, our results provide the first empirical dataset of ENSO-related δ18O anomalies spanning the tropical Pacific across a complete ENSO cycle, with applications to data-model intercomparison studies and investigations of tropical Pacific hydroclimatic processes. 

  PublisherDOI

• Multidisciplinary care in pediatric severe asthma: A comparative outcomes analysis

  Journal of Allergy and Clinical Immunology Global · 2025-01-18 · 3 citations

  articleOpen access

  Background: There are limited data comparing the effectiveness of multidisciplinary severe asthma clinics (SACs) with that of conventional single-discipline clinics (SDCs) for pediatric severe asthma. Objective: Our aim was to compare asthma outcomes between SACs and SDCs clinics and examine longitudinal health outcomes for patients with severe asthma who were followed in SACs. Methods: We conducted a retrospective cohort study comparing pediatric asthma outcomes among patients with severe asthma between 2018 and 2022 who were treated at the multidisciplinary Arkansas Children's SAC with those of patients with severe asthma treated at SDCs. The primary outcome was acute health care utilization, including hospitalizations and emergency department visits. Secondary outcomes included systemic corticosteroid prescriptions and controller medications. For SAC enrollees, longitudinal outcomes including health care utilization, symptom control, and spirometry were evaluated 12 months before and after enrollment. Data sources included the electronic health record and SAC patient registry. Results: = .02]). Conclusions: The study highlights significant morbidity among predominately Black pediatric patients with severe asthma, particularly those followed in a SAC versus in SDCs at a tertiary care referral center. The findings demonstrate the value of targeted multidisciplinary approaches to reduce asthma utilization and improve outcomes among high-risk patients.

  PublisherDOI

• A Coral Diagenesis and Physiology Framework for Improving Coral δ ¹⁸ O Paleoclimate Reconstructions

  Paleoceanography and Paleoclimatology · 2025-11-25

  articleOpen access

  Abstract Reef‐building corals provide seasonally resolved records of past climate variability based on the oxygen isotope composition (δ 18 O) of their skeletons. However, many non‐climatic factors can alter coral δ 18 O values. These include coral biomineralization and post‐depositional alteration of the coral skeleton, which can add uncertainty to coral based paleoclimate reconstructions. These uncertainties are apparent in mean climate reconstructions developed from coral δ 18 O values. We present a framework to minimize this uncertainty in mean coral δ 18 O records using a multi‐variate regression model that incorporates four commonly measured properties in coral δ 18 O records. We test the ability of the model to reduce variability in a Holocene climate reconstruction comprised of 37 coral δ 18 O records from Kiritimati. 38% of the variance in the mean coral δ 18 O values across the Holocene is accounted for by a combination of four predictors: (a) mm‐scale variability in coral δ 18 O, (b) the mean coral δ 13 C value, (c) the mean coral extension rate, and (d) the extent of diagenetic alteration identified in Scanning Electron Microscope images. Once these non‐climatic artifacts are minimized in the reconstruction, the weighted variance of the Holocene data set is reduced by 43% and the uncertainty in the trend of mean coral δ 18 O is reduced by 18%. The model is validated using three well‐characterized modern coral records with pristine and altered sections. These results have important implications for the climate interpretation of this Holocene data set. This framework also has the potential to improve other paleoclimate reconstructions based on ensembles of mean coral δ 18 O records.

  PublisherOA PDFDOI

• Tropical temperature evolution across two glacial cycles derived from speleothem fluid inclusion microthermometry

  2025-02-21 · 1 citations

  preprintOpen access

  Abstract. The evolution of tropical temperature across multiple glacial-interglacial cycles is mostly constrained with marine proxy records, which are associated with considerable uncertainties. Here we present a reconstruction of tropical land temperatures derived from fluid inclusions in stalagmite WR5_B from Whiterock Cave (Gunung Mulu National Park, Northern Borneo). The employed paleothermometer – nucleation-assisted microthermometry – is based on the density of the water trapped in fluid inclusions, i.e., on a well-known thermodynamic parameter and yields highly precise temperature estimates. The record consists of 49 temperature data points spanning a 127 kyr period from 460 to 333 ka including the glacial terminations T-V and T-IV. We find that Borneo temperature tracks Southern hemisphere temperature and atmospheric CO2 concentrations. Deglacial warming is accompanied by relatively dry conditions in Northern Borneo, indicated by pronounced enrichments in calcite δ18Occ and reconstructed drip water δ18Odw values. The amplitude of glacial-interglacial temperature changes amounts to 4.2 ± 0.4 °C (2SEM) between MIS 12 and the MIS 11 interglacial optimum and 4.3 ± 0.4 °C (2SEM) across T-IV. MIS 11 peak temperature was found to be 0.9 ± 0.4 °C warmer than late Holocene temperatures reconstructed for Whiterock Cave, whereas temperatures during MIS 12 and MIS 10 glacial maxima in our record are indistinguishable from those previously reconstructed for the Last Glacial Maximum. Both the present WR5_B record as well as the recently published record from Løland et al. (2022) covering the last glacial Termination exhibit a clear linear correlation with Antarctic temperature anomalies (R2 = 0.89 and 0.97, respectively), with practically identical slopes of the linear regression lines. Depending on the employed Antarctic ΔT reconstruction, Landais et al. (2021) and Jouzel et al. (2007), we found a polar amplification factor of 2.21 ± 0.22 and 2.42 ± 0.23 (95 % CI), respectively.

  PublisherDOI

• Tropical temperature evolution across two glacial cycles derived from speleothem fluid inclusion microthermometry

  Climate of the past · 2025-09-08 · 2 citations

  articleOpen access

  Abstract. The evolution of tropical temperature across multiple glacial-interglacial cycles is mostly constrained with marine proxy records, which are associated with considerable uncertainties. Here we present a reconstruction of tropical cave temperatures derived from fluid inclusions in stalagmite WR5_B from Whiterock Cave (Gunung Mulu National Park, Northern Borneo). The employed paleothermometer – nucleation-assisted microthermometry – is based on the density of the water trapped in fluid inclusions, i.e., on a well-known thermodynamic parameter and yields highly precise temperature estimates. The record consists of 49 temperature data points spanning a 127 kyr period from 460 to 333 ka including the glacial terminations T-V and T-IV. We find that Borneo temperature tracks Southern Hemisphere temperature and atmospheric CO2 concentrations. Deglacial warming is accompanied by relatively dry conditions in Northern Borneo, indicated by pronounced enrichments in calcite δ18Occ and reconstructed drip water δ18Odw values. The amplitude of glacial-interglacial temperature changes amounts to 4.2 ± 0.4 °C (2 SEM) between MIS 12 and the MIS 11 interglacial optimum and 4.3 ± 0.4 °C (2 SEM) across T-IV. MIS 11 peak temperature was found to be 0.9 ± 0.4 °C warmer than late Holocene temperatures reconstructed for Whiterock Cave, whereas temperatures during MIS 12 and MIS 10 glacial maxima in our record are indistinguishable from those previously reconstructed for the Last Glacial Maximum. Both the present WR5_B record as well as the recently published record from Løland et al. (2022) covering the last glacial Termination exhibit a clear linear correlation with Antarctic temperature anomalies (R2=0.89 and 0.97, respectively), with practically identical slopes of the linear regression lines. Depending on the employed Antarctic ΔT reconstruction, Landais et al. (2021) and Jouzel et al. (2007), we found a site-specific polar (Antarctic) amplification factor of 2.21 ± 0.22 and 2.42 ± 0.23 (95 % CI), respectively.

  PublisherOA PDFDOI

• Modes of climate variability: Synthesis and review of proxy-based reconstructions through the Holocene

  UNC Libraries · 2025-06-26

  articleOpen access
  PublisherDOI

• Western Pacific Warm Pool δ¹⁸O Response to the El Niño‐Southern Oscillation

  Geophysical Research Letters · 2025-02-04 · 7 citations

  articleOpen access

  Abstract Tropical Pacific seawater and precipitation stable oxygen isotope data aid in understanding modern oceanic and atmospheric interactions, and these data are particularly valuable as they are archived in isotope‐based paleoclimate records. However, the absence of modern seawater isotope time series limits the ability to identify the atmospheric influences on these data, precluding robust paleoclimate interpretations. We present a new 10 year sub‐monthly record of seawater and precipitation stable oxygen isotope values (δ 18 O sw and δ 18 O p ) from Koror, Palau. Our dataset indicates that temporally, δ 18 O sw is strongly influenced by local δ 18 O p. Both monthly δ 18 O sw and δ 18 O p are highly correlated with outgoing longwave radiation across the tropical Pacific, reflecting a Walker Circulation imprint on the surface ocean. Changes in the Palau δ 18 O sw —salinity relationship correspond to NINO3.4 variability, indicating a difference in how these variables record El Niño Southern Oscillation (ENSO) information, but demonstrating the utility of δ 18 O sw to reconstruct ENSO variability in the western tropical Pacific.

  PublisherOA PDFDOI

• Central equatorial Pacific climate change over the last 7,000 years using a coral ensemble approach

  2024-03-08

  preprintOpen access

  Identifying the processes that control tropical Pacific climate variations on long timescales is a pressing problem in climate research, given the outsized impacts of the El Niño/Southern Oscillation (ENSO) on global climate and the uncertainty in future ENSO behavior under anthropogenic climate change. By studying the characteristics of tropical Pacific climate under different climate states in the past, we can better assess its sensitivity to external forcing. Such paleoclimate constraints can serve as critically important test beds for coupled climate models that underlie future climate projections. In this talk, I will present a new set of climate reconstructions from the central equatorial Pacific spanning a range of timescales from seasonal to interannual to millennial, based on a large ensemble of coral oxygen isotope measurements from Kiritimati (aka Christmas Island) that span the past 7,000 years. Each of these timescales yields unique and complementary information about the climate of this region. We implement several new techniques to minimize the uncertainty in the climate reconstructions, which show a trend toward cooler and/or drier conditions and a reduced annual cycle going back in time that provide much needed context for understanding low-frequency changes in ENSO variability over the Holocene.

  PublisherDOI

Recent grants

• Collaborative Research: Fossil Coral Records of ENSO and Tropical Pacific Climate Through the Late Holocene

  NSF · $174k · 2008–2013

• RAPID Collaborative Research: Tracking coral reef impacts of the 2014/2015 El Nino event

  NSF · $34k · 2014–2015

• Collaborative Research: P2C2--Controls on Water Isotope Variability in the Tropical Pacific: A Strategy to Improve Paleoclimate Interpretations

  NSF · $226k · 2012–2016

• RAPID Collaborative Research: Ground Truthing Coral Proxy Reconstructions of ENSO by Observing the 2014-15 El Nino

  NSF · $27k · 2014–2015

• Ensemble Estimation of Central Tropical Pacific Climate over the last 6,000 Years

  NSF · $550k · 2015–2019

Frequent coauthors

• Hussein R. Sayani

  Florida State University

  50 shared

• Hai Cheng

  Xi'an Jiaotong University

  38 shared

• Pamela R. Grothe

  University of Mary Washington

  36 shared

• C.D. Charles

  Scripps Institution of Oceanography

  33 shared

• Jess F. Adkins

  California Institute of Technology

  32 shared

• Julien Emile‐Geay

  University of Southern California

  27 shared

• Alyssa R. Atwood

  26 shared

• David Noone

  University of Auckland

  26 shared

Education

• PhD, Oceanography

  University of California San Diego Scripps Institution of Oceanography

  2002

• BA in Geology & Geophysics and Biology, with Honors, Geology & Geophysics; Biology

  Yale University

  1996

Awards & honors

• NSF CAREER Award
• Presidential Early Career Award for Scientists and Engineers
• Hans Oeschger Medal from the European Geosciences Union (201…
• Elected as an AAAS Fellow (2021)
• Lead Author for the IPCC Sixth Assessment Report (2021)