John S Kimball

Dados Biográficos

ID6822667
NOMEJohn S Kimball
PRENOMESJohn S
SOBRENOMEKimball
ASSINATURAKIMBALL J S
AFILIAÇÕESUniversity of Montana
ORCID0000-0002-5493-5878
VERIFICADOSim
TOTAL DE OBRAS21
TOTAL DE CITAÇÕES0
TOTAL COMO AUTOR21
TOTAL COMO EDITOR0
PRIMEIRO ANO DE PUBLICAÇÃO2010
ANO MAIS RECENTE DE PUBLICAÇÃO2025
ÍNDICE H0

  • Assessing rain-on-snow event dynamics over Alaska using 30 year satellite microwave observations

    Open AccessJinyang Du, P B Kirchner et al.ARTICLEEnvironmental Research Letters2025

    Rain-on-snow (ROS) events are characterized by liquid precipitation or condensation onto snow surfaces that can lead to snowmelt and the formation of ice layers. ROS events can directly alter the physical structure and thermal properties of the snowpack, leading to rapid melting and runoff-induced flooding, reduced snow insulation, and permafrost degradation. However, tracking ROS events and regional trends remain uncertain due to limited ground …

  • Integrating multi-source remote sensing data for mapping boreal forest canopy height and species in interior Alaska in support of radar modeling

    Open AccessYuhuan Zhao, Yu-Huan Zhao et al.ARTICLEEnvironmental Research Letters2024

    Vegetation information is essential for analyzing aboveground biomass and understanding subsurface characteristics, such as root biomass, soil organic matter, and soil moisture conditions. In this study, we mapped boreal forest canopy height (FCH) and forest species (FS) distributions in the Delta Junction region of interior Alaska, by integrating multi-source remote sensing observations within a machine learning framework based on the extreme gr…

  • Maps of active layer thickness in northern Alaska by upscaling P-band polarimetric synthetic aperture radar retrievals

    Open AccessJ Whitcomb, Richard Chen et al.ARTICLEEnvironmental Research Letters2023

    Extensive, detailed information on the spatial distribution of active layer thickness (ALT) in northern Alaska and how it evolves over time could greatly aid efforts to assess the effects of climate change on the region and also help to quantify greenhouse gas emissions generated due to permafrost thaw. For this reason, we have been developing high-resolution maps of ALT throughout northern Alaska. The maps are produced by upscaling from high-res…

  • Widespread deepening of the active layer in northern permafrost regions from 2003 to 2020

    Open AccessZhihua Liu, John S Kimball et al.ARTICLEEnvironmental Research Letters2023

    The changing thermal state of permafrost is an important indicator of climate change in northern high latitude ecosystems. The seasonally thawed soil active layer thickness (ALT) overlying permafrost may be deepening as a consequence of enhanced polar warming and widespread permafrost thaw in northern permafrost regions (NPRs). The associated increase in ALT may have cascading effects on ecological and hydrological processes that impact climate f…

  • A model to characterize soil moisture and organic matter profiles in the permafrost active layer in support of radar remote sensing in Alaskan Arctic tundra

    Open AccessKazem Bakian-Dogaheh, Richard H Chen et al.ARTICLEEnvironmental Research Letters2022

    Organic matter (OM) content and a shallow water table are two key variables that govern the physical properties of the subsurface within the active layer of arctic soils underlain by permafrost, where the majority of biogeochemical activities take place. A detailed understanding of the soil moisture and OM profile behavior over short vertical distances through the active layer is needed to adequately model the subsurface physical processes. To ob…

  • Siberian 2020 heatwave increased spring CO 2 uptake but not annual CO 2 uptake

    Open AccessMin Jung Kwon, Ashley P Ballantyne et al.ARTICLEEnvironmental Research Letters2021

    Siberia experienced an unprecedented strong and persistent heatwave in winter to spring of 2020. Using bottom–up and top–down approaches, we evaluated seasonal and annual CO 2 fluxes of 2020 in the northern hemisphere (north of 30 °N), focusing on Siberia where the pronounced heatwave occurred. We found that, over Siberia, CO 2 respiration loss in response to the pronounced positive winter temperature anomaly was greater than in previous years. H…

  • Soil respiration strongly offsets carbon uptake in Alaska and Northwest Canada

    Open AccessJennifer D Watts, Susan M Natali et al.ARTICLEEnvironmental Research Letters2021

    Soil respiration (i.e. from soils and roots) provides one of the largest global fluxes of carbon dioxide (CO 2 ) to the atmosphere and is likely to increase with warming, yet the magnitude of soil respiration from rapidly thawing Arctic-boreal regions is not well understood. To address this knowledge gap, we first compiled a new CO 2 flux database for permafrost-affected tundra and boreal ecosystems in Alaska and Northwest Canada. We then used th…

  • Below-surface water mediates the response of African forests to reduced rainfall

    Open AccessNima Madani, John S Kimball et al.ARTICLEEnvironmental Research Letters2020

    Terrestrial ecosystem gross primary productivity (GPP) is the largest land-atmosphere carbon flux and the primary mechanism of photosynthetic fixation of atmospheric CO 2 into plant biomass. Anomalous rainfall events have been shown to have a great impact on the global carbon cycle. However, less is known about the impact of these events on GPP, especially in Africa, where in situ observations are sparse. Here, we use a suite of satellite and oth…

  • Impacts of the 2017 flash drought in the US Northern plains informed by satellite-based evapotranspiration and solar-induced fluorescence

    Open AccessMingzhu He, John S Kimball et al.ARTICLEEnvironmental Research Letters2019

    Drought is increasing in frequency and severity, exacerbating food and water security risks in an era of continued global warming and human population growth. Here, we analyzed a severe summer drought affecting the US Northern Plains region in 2017. We examined the spatial pattern and seasonal progression of vegetation productivity and water use in the region using satellite-based estimates of field-scale (30 m) cropland evapotranspiration (ET), …

  • Integrating snow science and wildlife ecology in Arctic-boreal North America

    Open AccessNatalie T Boelman, Glen E Liston et al.ARTICLEEnvironmental Research Letters2018

    Snow covers Arctic and boreal regions (ABRs) for approximately 9 months of the year, thus snowscapes dominate the form and function of tundra and boreal ecosystems. In recent decades, Arctic warming has changed the snowcover's spatial extent and distribution, as well as its seasonal timing and duration, while also altering the physical characteristics of the snowpack. Understanding the little studied effects of changing snowscapes on its wildlife…

  • Quantifying the effects of freeze-thaw transitions and snowpack melt on land surface albedo and energy exchange over Alaska and Western Canada

    Open AccessYoungwook Kim, John S Kimball et al.ARTICLEEnvironmental Research Letters2018

    Variations in land surface albedo and snow-cover strongly impact the global biosphere, particularly through the snow-albedo feedback on climate. The seasonal freeze-thaw (FT) transition is coupled with snowpack melt dynamics and strongly impacts surface water mobility and the energy budget in the northern (≥45°N) arctic and boreal region (ABR). However, understanding of the regional variation in snowmelt and its effect on the surface energy budge…

  • Rain-on-snow events in Alaska, their frequency and distribution from satellite observations

    Open AccessCaleb G Pan, P B Kirchner et al.ARTICLEEnvironmental Research Letters2018

    Wet snow and the icing events that frequently follow wintertime rain-on-snow (ROS) affect high latitude ecosystems at multiple spatial and temporal scales, including hydrology, carbon cycle, wildlife, and human development. However, the distribution of ROS events and their response to climatic changes are uncertain. In this study, we quantified ROS spatiotemporal variability across Alaska during the cold season (November to March) and clarified t…

  • Satellite-observed changes in vegetation sensitivities to surface soil moisture and total water storage variations since the 2011 Texas drought

    Open AccessA Geruo, I Velicogna et al.ARTICLEEnvironmental Research Letters2017

    We combine soil moisture (SM) data from AMSR-E and AMSR-2, and changes in terrestrial water storage (TWS) from time-variable gravity data from GRACE to delineate and characterize the evolution of drought and its impact on vegetation growth. GRACE-derived TWS provides spatially continuous observations of changes in overall water supply and regional drought extent, persistence and severity, while satellite-derived SM provides enhanced delineation o…

  • Impact of changes in GRACE derived terrestrial water storage on vegetation growth in Eurasia

    Open AccessI Velicogna, John S Kimball et al.ARTICLEEnvironmental Research Letters2015

    We use GRACE-derived terrestrial water storage (TWS) and ERA-interim air temperature, as proxy for available water and temperature constraints on vegetation productivity, inferred from MODIS satellite normalized difference vegetation index (NDVI), in Northern Eurasia during 2002-2011. We investigate how changes in TWS affect the correlation between NDVI and temperature during the non-frozen season. We find that vegetation growth exhibits signific…

  • Sunlight mediated seasonality in canopy structure and photosynthetic activity of Amazonian rainforests

    Open AccessJian Bi, Yuri Knyazikhin et al.ARTICLEEnvironmental Research Letters2015

    Resolving the debate surrounding the nature and controls of seasonal variation in the structure and metabolism of Amazonian rainforests is critical to understanding their response to climate change. In situ studies have observed higher photosynthetic and evapotranspiration rates, increased litterfall and leaf flushing during the Sunlight-rich dry season. Satellite data also indicated higher greenness level, a proven surrogate of photosynthetic ca…

  • New satellite climate data records indicate strong coupling between recent frozen season changes and snow cover over high northern latitudes

    Open AccessYoungwook Kim, John S Kimball et al.ARTICLEEnvironmental Research Letters2015

    We examined new satellite climate data records documenting frozen (FR) season and snow cover extent (SCE) changes from 1979 to 2011 over all northern vegetated land areas (≥45 °N). New insight on the spatial and temporal characteristics of seasonal FR ground and snowpack melt changes were revealed by integrating the independent FR and SCE data records. Similar decreasing trends in annual FR and SCE durations coincided with widespread warming (0.4…

  • Spring hydrology determines summer net carbon uptake in northern ecosystems

    Open AccessYonghong Yi, John S Kimball et al.ARTICLEEnvironmental Research Letters2014

    Increased photosynthetic activity and enhanced seasonal CO _2 exchange of northern ecosystems have been observed from a variety of sources including satellite vegetation indices (such as the normalized difference vegetation index; NDVI) and atmospheric CO _2 measurements. Most of these changes have been attributed to strong warming trends in the northern high latitudes (⩾50° N). Here we analyze the interannual variation of summer net carbon uptak…

  • Asynchronous Amazon forest canopy phenology indicates adaptation to both water and light availability

    Open AccessMichael O Jones, Matthew O Jones et al.ARTICLEEnvironmental Research Letters2014

    Amazon forests represent nearly half of all tropical vegetation biomass and, through photosynthesis and respiration, annually process more than twice the amount of estimated carbon (CO2) from fossil fuel emissions. Yet the seasonality of Amazon canopy cover, and the extent to which seasonal fluctuations in water availability and photosynthetically available radiation influence these processes, is still poorly understood. Implementing six remotely…

  • Surface water inundation in the boreal-Arctic

    Open AccessJennifer D Watts, John S Kimball et al.ARTICLEEnvironmental Research Letters2014

    Northern wetlands may be vulnerable to increased carbon losses from methane (CH4), a potent greenhouse gas, under current warming trends. However, the dynamic nature of open water inundation and wetting/drying patterns may constrain regional emissions, offsetting the potential magnitude of methane release. Here we conduct a satellite data driven model investigation of the combined effects of surface warming and moisture variability on high northe…

  • Sensitivity of inferred climate model skill to evaluation decisions

    Open AccessChristopher R Schwalm, Deborah N Huntinzger et al.ARTICLEEnvironmental Research Letters2013

    Confrontation of climate models with observationally-based reference datasets is widespread and integral to model development. These comparisons yield skill metrics quantifying the mismatch between simulated and reference values and also involve analyst choices, or meta-parameters, in structuring the analysis. Here, we systematically vary five such meta-parameters (reference dataset, spatial resolution, regridding approach, land mask, and time pe…

  • Recent decline in the global land evapotranspiration trend due to limited moisture supply

    Open AccessMartin Jung, Markus Reichstein et al.ARTICLENature2010