Article
Meteorology & Atmospheric Sciences
Linette N. Boisvert, Melinda A. Webster, Chelsea L. Parker, Richard M. Forbes
Summary: The Arctic is experiencing faster warming, resulting in increased rainfall days and longer rain seasons, mainly in the autumn and in the North Atlantic and peripheral seas. Compared to other reanalysis datasets and CloudSat observations, ERA-Interim overestimates both the number of rainfall days and the amount of rainfall at temperatures below freezing, due to the employed cloud microphysics scheme.
JOURNAL OF CLIMATE
(2023)
Article
Meteorology & Atmospheric Sciences
Shoudong Zhao, Minghu Ding, Wenqian Zhang, Ting Wei, Wei Cheng, Junming Chen, Cunde Xiao
Summary: Research indicates that changes in extreme temperatures have a greater impact on ecosystems and human society than changes in climate averages. The Arctic, a hotspot of global warming, has recently experienced unprecedented heatwaves, which emphasizes the need to identify long-term variations in extreme temperatures. However, spatial imbalance of observations and arbitrarily chosen investigation periods limit our understanding of extreme temperatures in the Arctic region. This study establishes a comprehensive and quality-controlled observation network for surface temperatures in the Arctic lands and combines in situ and reanalysis data to assess changes in extreme temperatures from 1979 to 2020. The results demonstrate an acceleration in the increase of extreme temperatures since the 2000s, particularly along the coast of Eurasia, and a larger magnitude of change for cold events compared to warm events.
JOURNAL OF CLIMATE
(2023)
Article
Computer Science, Artificial Intelligence
Arsam Aryandoust, Anthony Patt, Stefan Pfenningert
Summary: To enable electrification of cities and achieve accurate predictions of electricity consumption, an active deep learning approach is developed to forecast electric load profiles at the scale of single buildings. By leveraging additional computation and remotely sensed data, active learning enables more accurate predictions with less data compared to passive learning.
NATURE MACHINE INTELLIGENCE
(2022)
Article
Meteorology & Atmospheric Sciences
James A. Carton, Gennady A. Chepurin
Summary: This paper introduces a new Regional Arctic Ocean/sea ice Reanalysis (RARE) system, which uses sequential data assimilation to constrain temperature and salinity using various data sources. It shows that increasing the resolution of the reanalysis system improves agreement with observations, enhancing currents, eddy kinetic energy, and heat and salt transports.
JOURNAL OF CLIMATE
(2023)
Article
Meteorology & Atmospheric Sciences
Alvaro Avila-Diaz, David H. Bromwich, Aaron B. Wilson, Flavio Justino, Sheng-Hung Wang
Summary: This study investigates the extreme climate indices over the North American Arctic using various reanalyses, and finds that ASRv2 and ERA5 demonstrate the best performances. The results show a consistent decrease in frequency and intensity of cold extremes over the past two decades, along with an increase in daily precipitation intensity. The study also highlights the significant influence of North Atlantic Oscillation and Arctic Oscillation on extreme climate indices in the Arctic region.
JOURNAL OF CLIMATE
(2021)
Article
Environmental Sciences
Ingo Sasgen, Annette Salles, Martin Wegmann, Bert Wouters, Xavier Fettweis, Brice P. Y. Noel, Christoph Beck
Summary: Glacier mass balances in Svalbard and northern Arctic Canada have been asynchronous since the 1990s, influenced by changes in atmospheric heat advection. These glaciers are highly responsive to climate change, showing the amplification of global warming and increasing mass loss.
NATURE CLIMATE CHANGE
(2022)
Article
Meteorology & Atmospheric Sciences
R. Przybylak, P. Wyszynski, A. Arazny
Summary: The main driving mechanisms behind the early-twentieth-century Arctic warming have not been fully recognized due to limited knowledge about the climate during that period. This study provides new insights into the surface air temperature conditions in the Arctic during the early-twentieth-century warming, compared to the contemporary Arctic warming. The results show that the magnitude of warming was greatest in the Pacific and Canadian Arctic regions, and the climate was more continental and less stable during the early-twentieth-century warming.
JOURNAL OF CLIMATE
(2022)
Article
Multidisciplinary Sciences
Donglai Jiao, Nannan Xu, Fan Yang, Ke Xu
Summary: ERA5 is the latest fifth-generation reanalysis global atmosphere dataset from the European Centre for Medium-Range Weather Forecasts, replacing ERA-Interim as the next generation of representative satellite-observational data on the global scale. ERA5 data have been evaluated and applied in different regions, but the performances are inconsistent. This study evaluates the temporal-spatial performance of ERA5 precipitation data from 1979 to 2018 based on gridded-ground meteorological station observational data across China, showing that ERA5 captures the patterns of observed precipitation well but slightly overestimates precipitation in the summer, with accuracy varying across different regions in China.
SCIENTIFIC REPORTS
(2021)
Article
Geosciences, Multidisciplinary
Rudong Zhang, Hailong Wang, Qiang Fu, Philip J. Rasch, Mingxuan Wu, Wieslaw Maslowski
Summary: The Arctic amplification (AA) is still an open question whether sea-ice loss or lapse-rate feedback dominates. Analysis suggests that changes in clear-sky downward longwave radiation contribute the most to the surface warming trend during the cold season, while a reduction in lower-tropospheric inversions plays a unique role in the downward longwave radiation reduction.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
A. Yamagami, M. Kajino, T. Maki, T. Toyoda
Summary: This study investigates the variability of aerosol optical depth (AOD) in the Arctic and its relationship with atmospheric disturbances on synoptic timescales. The results show that AOD in the Arctic is strongly correlated with observations, and organic carbon aerosols derived from biomass burning over northern Eurasia and northern North America are the dominant components. Additionally, the locations of synoptic disturbances are related to high-AOD events, and the development of Arctic cyclones in northern Eurasia plays a crucial role in aerosol transport, aging, and deposition during summer.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Guokun Lyu, Armin Koehl, Nuno Serra, Detlef Stammer, Jiping Xie
Summary: A new Arctic ocean-sea ice reanalysis for the period 2007-2016 is presented, showing substantial improvement in SST, SIC, and SIT after assimilating ocean and sea ice observations. The reanalysis compares well with previous analyses for SIC and SST, but differences remain in freshwater content and transport properties.
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2021)
Article
Engineering, Marine
Joseph Kim, Enda Murphy, Ioan Nistor, Sean Ferguson, Mitchel Provan
Summary: A numerical study investigated storm surge hazards in Canada's western Arctic using the ERA5 dataset. The study found that decreasing sea ice and the duration of the ice season in the Arctic may lead to increased risk from storm surge-driven hazards. The numerical model, adjusted with wind drag coefficients, accurately predicted storm surges for most simulated events, highlighting the importance of non-conventional data sources in coastal hazard assessments.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Environmental Sciences
Jia Tao, Xiao Cheng, Lei Zheng, Xiong-Xin Xiao, Xin-Yue Zhong, Qi Liang, Zi-Qian Zhang, Hong Lin
Summary: This study evaluates the performance of reanalysis datasets in determining rain-on-snow (ROS) events. It finds that all reanalysis datasets show poor performance in identifying ROS events due to the low accuracy of rainfall data. However, the spatial distribution and hot spots of ROS are similar among the datasets, mainly located on the coast of Alaska, Norway, and Greenland. Additionally, rainy days increase but there is little overall change in ROS events. Therefore, alternative strategies are urgently needed to investigate ROS events at a large scale in the changing Arctic.
ADVANCES IN CLIMATE CHANGE RESEARCH
(2023)
Article
Multidisciplinary Sciences
Ziqi Ma, Jianbin Huang, Xiangdong Zhang, Yong Luo, Minghu Ding, Jun Wen, Weixin Jin, Chen Qiao, Yifu Yin
Summary: Developing a precise Arctic surface air temperature (SAT) dataset is crucial for monitoring the rapid climate change in the Arctic and improving our understanding of it. This study reconstructed a new monthly gridded Arctic SAT dataset dating back to 1979 using a deep learning method and combining data from multiple sources. This dataset represents a significant improvement in developing observational temperature datasets and has various potential applications.
Article
Environmental Sciences
Nicole A. Loeb, Alex Crawford, Julienne C. Stroeve, John Hanesiak
Summary: The study compares three recent atmospheric reanalyses to surface precipitation observations in the Eastern Canadian Arctic and Greenland from 1980 to 2016. While the reanalyses struggled to match observed accumulations from individual events, they were able to match the observed seasonality of precipitation extremes. ERA-5 showed slightly higher correlations and lower biases compared to MERRA-2 and CFSR, but all three products had similar performance in general.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Environmental Sciences
Howard E. Epstein, Donald A. Walker, Gerald Frost, Martha K. Raynolds, Uma Bhatt, Ronald Daanen, Bruce Forbes, Jozsef Geml, Elina Kaarlejarvi, Olga Khitun, Artem Khomutov, Patrick Kuss, Marina Leibman, Georgy Matyshak, Nataliya Moskalenko, Pavel Orekhov, Vladimir E. Romanovsky, Ina Timling
Summary: Field sampling along the Eurasia Arctic Transect in northwestern Siberia showed that aboveground vegetation biomass, NDVI, and LAI all increased with the summer warmth index. Different soil types influenced the spatial patterns of these vegetation properties. Shrub biomass increased non-linearly with summer warmth index, while moss and lichen biomass responded differently to the increase in temperature.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Uma S. Bhatt, Donald A. Walker, Martha K. Raynolds, John E. Walsh, Peter A. Bieniek, Lei Cai, Josefino C. Comiso, Howard E. Epstein, Gerald Frost, Robert Gersten, Amy S. Hendricks, Jorge E. Pinzon, Larry Stock, Compton J. Tucker
Summary: This study investigates climate drivers of tundra vegetation trends and variability over the 1982-2019 period using an indicators framework. The study finds that changes in spring sea-ice continue to drive variations in other indicators, leading to increases in summer open-water, summer warmth, MaxNDVI, and TI-NDVI. However, the strong upward trends in MaxNDVI and TI-NDVI are weakening and becoming more variable as the ice retreats from coastal areas.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Christopher William Smith, Santosh K. Panda, Uma Suren Bhatt, Franz J. Meyer
Summary: This study utilized high spatial and spectral resolution AVIRIS-NG hyperspectral data to generate more accurate fire fuel maps compared to those generated using low resolution Landsat 8 data. The accuracy was significantly higher and more vegetation classes were identified, demonstrating the value of AVIRIS-NG for providing decision-support information to fire managers.
Article
Environmental Sciences
Anushree Badola, Santosh K. Panda, Dar A. Roberts, Christine F. Waigl, Uma S. Bhatt, Christopher W. Smith, Randi R. Jandt
Summary: The study simulated hyperspectral data from Sentinel-2 multispectral data using the spectral response function of the AVIRIS-NG sensor, achieving a high classification accuracy of 89% for tree species classification. The simulated hyperspectral data showed a high correlation with real AVIRIS-NG data and outperformed Sentinel-2 data in terms of accuracy. The study demonstrated the potential of generating low-cost and high-quality hyperspectral data from Sentinel-2 data for improved land cover and vegetation mapping in boreal forests.
Article
Environmental Sciences
Christopher W. Smith, Santosh K. Panda, Uma S. Bhatt, Franz J. Meyer, Anushree Badola, Jennifer L. Hrobak
Summary: Recent advancements in remote sensing methods and satellite imagery have the potential to greatly enhance burn severity assessments in the Alaskan boreal forest. Machine learning classifiers show promise for reliable mapping of burn severity when sufficient ground truth data is available.
Article
Environmental Sciences
Rick Lader, Pamela Sousanes, Uma S. Bhatt, John E. Walsh, Peter A. Bieniek
Summary: Landslides along road corridors in Alaska national parks pose threats to public safety, visitor access, subsistence activities, and result in costly remediation of damaged infrastructure. The risk of landslides in these areas is associated with near-surface permafrost, mean annual air temperatures above freezing, and heavy precipitation events. Climate model projections indicate that the warming temperatures and increased precipitation in the future will result in elevated landslide risk in the road corridors of these national parks.
Article
Geosciences, Multidisciplinary
Edward Blanchard-Wrigglesworth, Mitchell Bushuk, Francois Massonnet, Lawrence C. Hamilton, Cecilia M. Bitz, Walter N. Meier, Uma S. Bhatt
Summary: We evaluated the skill of Arctic September sea ice forecasts in the Sea Ice Outlook from 2008 to 2022. The multi-model median forecast initialized in June showed slightly higher skill than a damped anomaly forecast, while the July and August initialized forecasts did not perform better. The individual dynamical and statistical forecasts had lower skill compared to the multi-model median forecast. The overall skill was lower than expected based on retrospective forecasts. Some forecasts initialized in early September 2021 and 2022 had physically improbable values. Spatial forecasts of sea ice concentration showed skill in multi-model forecasts and improvement in individual forecast skill in recent years. Initial conditions exhibited large spread in sea ice volume and a positive correlation between initialized sea ice volume and September SIE forecast. Forecast error was influenced by summer weather.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Letter
Biodiversity Conservation
Gerald V. Frost, Uma S. Bhatt, Matthew J. Macander, Howard E. Epstein, Martha K. Raynolds, Christine F. Waigl, Donald A. Walker
GLOBAL CHANGE BIOLOGY
(2023)
Article
Environmental Sciences
Anushree Badola, Santosh K. Panda, David R. Thompson, Dar A. Roberts, Christine F. Waigl, Uma S. Bhatt
Summary: Wildfires in the boreal ecosystem of Alaska have been increasing in frequency and size due to favorable environmental conditions. The dominant needleleaf vegetation, with its high flammability, plays a crucial role in these fires. Understanding its distribution is important for effective forest and wildfire management.
Article
Environmental Sciences
Hannah Mevenkamp, Nico Wunderling, Uma Bhatt, Tobey Carman, Jonathan Friedemann Donges, Helene Genet, Shawn Serbin, Ricarda Winkelmann, Eugenie Susanne Euskirchen
Summary: Climate change has significant impacts on Earth's ecosystems and carbon budgets, potentially shifting the Arctic from a carbon sink to a source. Uncertainties in terrestrial biosphere models (TBMs) challenge the prediction of this switch. One major source of uncertainty is model parameterization, resulting from a mismatch between available data and model needs.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
Jun Meng, Jingfang Fan, Uma S. Bhatt, Juergen Kurths
Summary: The decline of Arctic sea ice is strongly correlated with global weather patterns, emphasizing the importance of understanding Arctic weather variability for accurate weather forecasting. The complex link between Arctic weather and the Arctic Oscillation is discovered, highlighting the increased variability in daily Arctic sea ice due to accelerated ice decline caused by global warming. This weather instability can affect broader regional patterns and pose risks to human activities and weather forecast predictability.
NATURE COMMUNICATIONS
(2023)
Article
Geosciences, Multidisciplinary
Rick Lader, Uma S. Bhatt, John E. Walsh, Peter A. Bieniek
Summary: This study investigates the observed trends and projected changes of hydroclimatic extremes indices in southeast Alaska. The results show mixed tendencies of precipitation variability but consistent trends towards warmer and wetter conditions. The models project increased precipitation, longer dry periods, and reduced snowfall.
EARTH INTERACTIONS
(2022)
Article
Environmental Studies
Uma S. Bhatt, Benjamin A. Carreras, Jose Miguel Reynolds Barredo, David E. Newman, Pere Collet, Damia Gomila
Summary: This study explores the impact of climate change on renewable energy supply and finds that this impact varies with location. It provides a framework to assess the optimal mix of renewables and changes in energy storage requirements, and demonstrates the effects on grid reliability and potential mitigation paths.
Article
Ecology
Sarah M. Thunberg, John E. Walsh, Eugenie S. Euskirchen, Kyle Redilla, Adrian Rocha
Summary: The study focused on the trajectory of land surface wetness in the Arctic climate system, aiming to document seasonal and interannual variations of surface moisture fluxes and evaluate the effects of wildfire disturbance on ET. Results showed that forest sites have a stronger dependence on relative humidity and wind speed, while tundra sites are more temperature-limited.
