About

Nicole Lovenduski is a Professor in the Atmospheric and Oceanic Sciences department at the University of Colorado Boulder and serves as the Director of INSTAAR. Her research focuses on the marine carbon cycle, ocean climate variability and change, and ocean modeling. She is involved in advancing understanding of oceanic processes and their impacts on climate systems, contributing to the scientific community through her leadership and research activities at CU Boulder.

Research topics

• Climatology
• Geology
• Environmental science
• Geography
• Meteorology
• Oceanography
• Computer Science
• Mathematics
• Chemistry
• Environmental resource management
• Ecology
• Atmospheric sciences
• Statistics

Selected publications

• Marine phytoplankton extremes and compound extreme events have the potential to be predicted multiple months in advance

  2026-02-04

  article

  Global marine primary producers, such as phytoplankton, are the base of the marine food web and vary on short timescales, characterized by seasonal blooms. There is growing concern about the occurrence of short-term extreme events in phytoplankton abundance, which may impact higher trophic levels and economically-important species. Previous work has investigated the occurrence and impacts of extremes, but forecasting of large-scale extremes has not been attempted. Here, we leverage the Community Earth System Model Seasonal-to-Multiyear Large Ensemble (CESM SMYLE) to assess the potential predictability of phytoplankton extremes. We find that low phytoplankton biomass extremes (LBX) are significantly predictable up to 6-months in advance. LBX are closely related to enhanced upper ocean stratification, which impacts nutrient availability. We find that compound events (LBX with marine heatwave and low oxygen extremes) are also significantly predictable multiple months in advance. These results could inform future model development with impacts for marine resource managers.

  PublisherDOI

• Atmospheric oxygen constraints on Southern Ocean productivity and drivers of carbon uptake

  Nature Geoscience · 2026-04-21 · 1 citations

  articleOpen access

  Ocean net primary production fixes dissolved carbon into organic matter while producing O2, driving the biological carbon pump that contributes to ocean CO2 uptake. The Southern Ocean plays a critical role in carbon export, yet its productivity estimates remain highly uncertain due to limited observations. Here we constrain Southern Ocean (south of ~44° S) net primary production by linking Coupled Model Intercomparison Project Phase 6 (CMIP6)-modelled productivity to modelled air–sea O2 fluxes and applying O2 flux estimates derived from airborne O2/N2 observations. We find an annual net primary production of 6.5 ± 1.36 PgC yr−1, substantially higher than most CMIP6 model and satellite-based estimates, but consistent with Argo oxygen-based estimates. We show that CMIP6 models with underestimated productivity exhibit weak summer CO2 uptake, with some also showing excessive summer temperature-driven outgassing. Together, these models produce incorrect seasonal CO2 flux cycles with summer outgassing, whereas observation-based estimates indicate summer uptake. These errors may stem from inadequate model representation of ocean vertical mixing, which affects nutrient supply, stratification and heat redistribution. Our productivity estimates provide quantitative benchmarks that, combined with constraints from airborne CO2 observations and surface ocean pCO2 and temperature observations, reduce uncertainty in estimates of model-projected end-of-century Southern Ocean CO2 uptake by 53%. Atmospheric oxygen sampling provides improved estimates of Southern Ocean net primary productivity, revealing that many Earth system models underestimate productivity in ways that bias both present-day and future projections of air–sea CO2 exchange.

  PublisherDOI

• Detectability of phytoplankton biomass extremes using simulated satellite chlorophyll observations

  2026-01-01

  article

  Extreme open-ocean phytoplankton events can influence marine ecosystems, yet their global occurrence, drivers, and consequences remain poorly understood. Most large-scale studies rely on satellite chlorophyll, which provides only a surface view, is affected by physiological variability, and is often missing due to clouds and low sunlight. Here, we use an Earth system model with a satellite chlorophyll simulator to test when and where vertically integrated phytoplankton biomass extremes align with satellite-detected chlorophyll extremes. Globally, about 10% of low and 19% of high phytoplankton biomass extremes are detected. The detection rate is the result of the combined impacts of missing data and extreme misalignment: only 34% of low and 56% of high detected chlorophyll extremes correspond with true biomass extremes, with the largest discrepancies occurring in the subtropical gyres. These findings highlight the need for caution when interpreting satellite chlorophyll as a proxy for phytoplankton biomass extremes.

  PublisherDOI

• Detectability of Phytoplankton Biomass Extremes Using Simulated Satellite Chlorophyll Observations

  Geophysical Research Letters · 2026-02-12

  articleOpen access

  Abstract Extreme open‐ocean phytoplankton events can influence marine ecosystems, yet their global occurrence, drivers, and consequences remain poorly understood. Most large‐scale studies rely on satellite chlorophyll, which provides only a surface view, is affected by physiological variability, and is often missing due to clouds and low sunlight. Here, we use an Earth system model with a satellite chlorophyll simulator to test when and where vertically integrated phytoplankton biomass extremes align with satellite‐detected chlorophyll extremes. Globally, about 10% of low and 19% of high phytoplankton biomass extremes are detected. The detection rate is the result of the combined impacts of missing data and extreme misalignment: only 34% of low and 56% of high detected chlorophyll extremes correspond with true biomass extremes, with the largest discrepancies occurring in the subtropical gyres. These findings highlight the need for caution when interpreting satellite chlorophyll as a proxy for phytoplankton biomass extremes.

  PublisherDOI

• Potential Impacts of Climate Interventions on Marine Ecosystems

  Reviews of Geophysics · 2026-01-14 · 3 citations

  articleOpen access

  Abstract Rising global temperatures pose significant risks to marine ecosystems, biodiversity, and fisheries. Recent comprehensive assessments suggest that large‐scale mitigation efforts to limit warming are falling short, and all feasible future climate projections, including those that represent optimistic emissions reductions, exceed the Paris Agreement's 1.5°C or 2° warming targets during this century. While avoiding further CO 2 emissions remains the most effective way to prevent environmental destabilization, interest is growing in climate interventions—deliberate, large‐scale manipulations of the environment aimed at reducing global warming. These include carbon dioxide removal (CDR) to reduce atmospheric CO 2 concentrations over time, and solar radiation modification (SRM), which reflects sunlight to lower surface temperatures but does not address root CO 2 causes. The effects of these interventions on marine ecosystems, both direct and in combination with ongoing climate change, remain highly uncertain. Given the ocean's central role in regulating Earth's climate and supporting global food security, understanding these potential effects is crucial. This review provides an overview of proposed intervention methodologies for marine CDR and SRM and outlines the potential trade‐offs and knowledge gaps associated with their impacts on marine ecosystems. Climate interventions have the potential to reduce warming‐driven impacts, but could also alter marine food systems, biodiversity and ecosystem function. Effects will vary by pathway, scale, and regional context. Pathway‐specific impact assessments are thus crucial to quantify trade‐offs between plausible intervention scenarios as well as to identify their expected impacts on marine ecosystems in order to prioritize scaling efforts for low‐risk pathways and avoid high‐risk scenarios.

  PublisherDOI

• Quantifying Under‐Ice Phytoplankton Blooms in the Changing Arctic and Southern Oceans

  Geophysical Research Letters · 2026-04-20

  articleOpen access

  Abstract Historically, polar marine phytoplankton were thought to primarily grow after the seasonal breakup of sea ice, when there is plentiful light available in the surface ocean. However, observations of substantial productivity under sea ice has called this assumption into question. Using a global Earth system model, we quantify under‐ice phytoplankton productivity in the Arctic and Southern Oceans. We find that phytoplankton growing under sea ice, which are invisible to remote sensing‐derived estimates of productivity, generate ∼100 Tg C yr −1 in each polar region. Additionally, while the sea ice conditions that permit under‐ice growth differ between the polar regions, in both poles the under‐ice blooms shift polewards and decline in importance near the end of the 21st century as sea ice loss accelerates. These changes likely have implications for food availability for the benthic and pelagic consumers in polar ecosystems and for global carbon cycling.

  PublisherDOI

• End-of-century Arctic Ocean phytoplankton blooms start a month earlier due to anthropogenic climate change

  Communications Earth & Environment · 2025-11-06 · 2 citations

  articleOpen access

  Abstract Phytoplankton net primary production in the Arctic has historically been constrained to a short, intense summer bloom that sustains fish, seabird, and marine mammal populations. However, climate change is altering Arctic phytoplankton bloom phenology. We use an ensemble of Earth system model simulations to isolate the impact of climate change on the timing, duration, and importance (relative contribution to total net primary production) of the bloom. Earlier blooms emerge across 71% of the Arctic Ocean by 2100, when blooms begin 34 days earlier and last 15 days longer than in 1970. Productivity is less concentrated in a single bloom in sub-Arctic seas and on Arctic inflow shelves by 2100, indicating that the bloom declines in importance. In contrast, bloom phenology and productivity exhibit only small changes by 2020. Our study demonstrates that anthropogenic climate change will greatly alter the timing and importance of the Arctic Ocean phytoplankton bloom by 2100.

  PublisherOA PDFDOI

• Potential impacts of climate interventions on marine ecosystems

  2025-11-24

  articleOpen access

  Climate intervention research is expanding as current mitigation efforts to limit warming below crucial targets are falling short. • Substantial knowledge gaps exist on the potential impacts of climate intervention strategies on marine ecological systems. • We review the potential impacts of climate intervention on marine ecosystems, including biotic and abiotic factors.

  PublisherOA PDFDOI

• Accessible Climate and Impact Model Output for Studying the Human and Environmental Impacts of Nuclear Conflict

  2025-10-03 · 2 citations

  articleOpen access

  ABSTRACT Nuclear winter refers to the suite of physical and biological consequences that may follow nuclear conflict, particularly the cooling and darkening of Earth's surface due to black carbon soot in the upper atmosphere. While the associated changes in temperature, precipitation, and food system productivity have been the subject of climate modelling for decades, the outputs of models used to project these effects are stored in large files with formats unfamiliar to the broader research community. This paper introduces a standardized, user‐friendly repository of simulated nuclear conflict climate impact data designed to lower barriers for non‐specialist researchers. The data product provides simplified, spreadsheet‐ready datasets derived from established Earth System Model simulations and includes variables relevant to human and environmental impacts: temperature, precipitation, ultraviolet radiation, crop yields, fish catch, and sea ice thickness for a range of nuclear conflict scenarios. This repository aims to facilitate interdisciplinary research into the long‐term consequences of nuclear detonations to support policy development.

  PublisherOA PDFDOI

• A U.S. Scientific Community Vision for Sustained Earth Observations of Greenhouse Gases to Support Local to Global Action

  AGU Advances · 2025-12-01 · 2 citations

  articleOpen access

  Abstract Managing carbon stocks in the land, ocean, and atmosphere under changing climate requires a globally‐integrated view of carbon cycle processes at local and regional scales. The growing Earth Observation (EO) record is the backbone of this multi‐scale system, providing local information with discrete coverage from surface measurements and regional information at global scale from satellites. Carbon flux information, anchored by inverse estimates from spaceborne Greenhouse Gas (GHG) concentrations, provides an important top‐down view of carbon emissions and sinks, but currently lacks global continuity at assessment and management scales (<100 km). Partial‐column data can help separate signals in the boundary layer from the overlying atmosphere, providing an opportunity to enhance surface sensitivity and bring flux resolution down from that of column‐integrated data (100–500 km). Based on a workshop held in September 2024, the carbon cycle community envisions a carbon observation system leveraging GHG partial columns in the lower and upper troposphere to weave together information across scales from surface and satellite EO data, and integration of top‐down/bottom‐up analyses to link process understanding to global assessment.

  PublisherOA PDFDOI

Recent grants

• The Variable and Changing Carbonate Chemistry of the Southern Ocean

  NSF · $454k · 2012–2017

• Collaborative Research: Forced drivers of trends in ocean biogeochemistry: Volcanos and atmospheric carbon dioxide

  NSF · $193k · 2020–2024

• CAREER: A change in the forecast: Ocean biogeochemistry over the next decade

  NSF · $800k · 2018–2026

• Collaborative Research: Uncertainty in Predictions of 21st Century Ocean Biogeochemical Change

  NSF · $367k · 2016–2021

Frequent coauthors

• Cara Nissen

  University of Colorado Boulder

  115 shared

• Galen A. McKinley

  103 shared

• Tessa Gorte

  University of Colorado System

  88 shared

• Keith Lindsay

  Climate and Global Dynamics Laboratory

  86 shared

• Jan T. M. Lenaerts

  University of Colorado Boulder

  85 shared

• Matthew C. Long

  NSF National Center for Atmospheric Research

  82 shared

• Kristen M. Krumhardt

  75 shared

• Jeffrey B. Weiss

  University of Colorado Boulder

  70 shared

Education

• Ph.D., Oceanography

  University of Washington

  2005

• M.S., Oceanography

  University of Washington

  2001

• B.S., Oceanography

  University of California, Santa Barbara

  1999