Article
Meteorology & Atmospheric Sciences
Dafydd Stephenson, F. Sevellec
Summary: This study introduces an optimization framework and computational method to investigate sources of ocean uncertainty, revealing that high-frequency variations in meridional transports are mainly wind-driven, while surface buoyancy forcing is the dominant source of uncertainty at lower frequencies. Mesoscale eddies contribute the most to year-averaged quantities in the subtropical region, but their impact is significantly reduced in the subpolar region.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Hyo-Jeong Kim, Soon-Il An, Jae-Heung Park, Mi-Kyung Sung, Daehyun Kim, Yeonju Choi, Jin-Soo Kim
Summary: Accurate representation of the Atlantic Meridional Overturning Circulation (AMOC) in global climate models is crucial for reliable future climate predictions and projections. In this study, the researchers analyzed low-frequency variability of the AMOC driven by the North Atlantic Oscillation (NAO) using 42 coupled atmosphere-ocean global climate models. The results showed that the influence of the simulated NAO on the AMOC differs significantly between the models due to the diverse oceanic mean state, especially over the subpolar North Atlantic (SPNA), where deep water formation of the AMOC occurs.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2023)
Review
Environmental Sciences
Laura C. Jackson, Arne Biastoch, Martha W. Buckley, Damien G. Desbruyeres, Eleanor Frajka-Williams, Ben Moat, Jon Robson
Summary: The Atlantic Meridional Overturning Circulation (AMOC) has a key role in the climate system, and its variability since 1980 has been analyzed. The AMOC has shown periods of both strengthening and weakening, with uncertain magnitudes of change. Different patterns of variability have been observed in the subpolar and subtropical regions of the North Atlantic. Research priorities include improving the monitoring of the AMOC, better representing processes in the North Atlantic, and distinguishing between anthropogenic weakening and internal variability.
NATURE REVIEWS EARTH & ENVIRONMENT
(2022)
Article
Meteorology & Atmospheric Sciences
David Barriopedro, Blanca Ayarzaguena, Marina Garcia-Burgos, Ricardo Garcia-Herrera
Summary: This study presents a comprehensive characterization of the North Atlantic eddy-driven jet (EDJ) using daily parameters based on low-tropospheric zonal wind data. The variability and complex configurations of the EDJ beyond latitude and intensity are described, allowing for a better understanding of its structure and influence on European climate. The variations in EDJ parameters reflect distinctive patterns of eddy forcing and wave breaking, with anticyclonic eddies playing a major role in shaping the EDJ structure.
Article
Meteorology & Atmospheric Sciences
Yuepeng Hu, Botao Zhou, Tingting Han, Huixin Li, Huijun Wang
Summary: Using the S-EOF analysis, this study finds an in-phase change of drought from spring to summer in Northeast China, associated with geopotential height anomalies around Lake Baikal. The study also shows that the spring NAO plays a significant role in the in-phase change of spring-summer droughts over Northeast China, through the combined effects of zonal wave train and central Siberian soil moisture. These findings contribute to a better understanding of drought in Northeast China and have implications for disaster prevention and mitigation.
JOURNAL OF CLIMATE
(2022)
Article
Environmental Sciences
Florian Boergel, H. E. Markus Meier, Matthias Groeger, Monika Rhein, Cyril Dutheil, Jan Moritz Kaiser
Summary: This study analyzes the impact of temperature variations in the North Atlantic on regional climate and identifies two different clusters of physical mechanisms in CMIP6 models. The first cluster shows a coherent relationship between the North Atlantic Oscillation (NAO) and the Atlantic Multidecadal Variability (AMV), resulting in decreased precipitation in Northern Europe. In contrast, the second cluster does not show significant coherence between NAO and AMV, but it leads to a low-pressure anomaly in the subpolar gyre and increased precipitation in Europe.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Dylan Oldenburg, Robert C. J. Wills, Kyle C. Armour, LuAnne Thompson, Laura C. Jackson
Summary: The study identifies modes of low-frequency North Atlantic Ocean Heat Transport (OHT) variability through Low-Frequency Component Analysis (LFCA), showing that changes in AMOC and OHT are primarily driven by variations in Labrador Sea deep convection.
JOURNAL OF CLIMATE
(2021)
Article
Meteorology & Atmospheric Sciences
Zhen Lv, Jun-Chao Yang, Xiaopei Lin, Yu Zhang
Summary: This study suggests that the North Atlantic forcing plays a more significant role than the tropical Pacific forcing in the decadal prediction of sea surface temperature (SST) variability in the North Pacific. By removing the North Atlantic forcing, the prediction skill of NP SST decreases, indicating its strong contribution to the long-term prediction. The research emphasizes the need for improving the simulation of the Atlantic trans-basin effect for better predicting NP climate.
JOURNAL OF CLIMATE
(2022)
Article
Environmental Sciences
Marie-Jose Messias, Herle Mercier
Summary: Understanding the history and redistribution of ocean excess heat uptake is crucial for assessing climate warming. This study reconstructs ocean heat content change in the 25 degrees N Atlantic hydrographic section and finds that the delayed response of the ocean below 700 m to sea surface temperature change contributes significantly to warming at this latitude. Recent research also shows an increasing net excess heat transport across 25 degrees N, indicating that excess heat redistribution is a key driver of North Atlantic heat gain.
COMMUNICATIONS EARTH & ENVIRONMENT
(2022)
Article
Multidisciplinary Sciences
Jingyu Liu, Yipeng Wang, Samuel L. Jaccard, Nan Wang, Xun Gong, Nianqiao Fang, Rui Bao
Summary: The poorly ventilated conditions in the North Atlantic were linked to enhanced pre-aged organic carbon input. The old organic carbon came mainly from terrigenous sources and was exported to the North Atlantic by ice-rafting. Ocean ventilation plays a crucial role in regulating carbon sequestration and release, which has significant implications for climate evolution.
NATURE COMMUNICATIONS
(2023)
Article
Meteorology & Atmospheric Sciences
Ben Harvey, Ed Hawkins, Rowan Sutton
Summary: Climate projections for the UK exhibit substantial uncertainty due to the dynamical changes of the regional atmospheric circulation. The extent of change in the North Atlantic jet and its impact on UK weather and climate are of particular importance. This article proposes the use of jet-based storylines to assess and communicate uncertainty in UK climate projections, providing a framework for evaluating a range of plausible future climate outcomes and their potential impacts. By constructing future jet storylines and evaluating their impact on UK precipitation, this approach increases confidence in projecting changes in UK precipitation associated with each storyline.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2023)
Article
Meteorology & Atmospheric Sciences
Ivana Herceg-Bulic, Sara Ivasic, Margareta Popovic
Summary: This study analyzes the impact of tropical sea surface temperatures (SSTs) on the signal of geopotential heights (GH200) over the North Atlantic-European (NAE) region. The results show that in late winter, the association between ENSO events and geopotential heights is the strongest. The influences of individual tropical basins are also competitive. Additionally, the superposition effect of extratropical North Atlantic SSTs is demonstrated through the modulation of storm tracks. The ENSO signature in the North Atlantic is projected onto the East Atlantic pattern.
NPJ CLIMATE AND ATMOSPHERIC SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Chengfei He, Amy C. Clement, Mark A. Cane, Lisa N. Murphy, Jeremy M. Klavans, Tyler M. Fenske
Summary: The subpolar North Atlantic has experienced a decrease in sea surface temperature over the past century, known as the warming hole. While it is commonly believed to be caused by the slowdown of the Atlantic meridional overturning circulation, this study shows that the atmosphere alone can account for a significant portion of the observed cooling trend. Increased local westerlies enhance heat loss from the ocean, leading to the cooling effect. Wind-driven ocean processes may also contribute to the cooling, but the ultimate driver remains in the atmosphere.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Multidisciplinary Sciences
Jiechun Deng, Aiguo Dai
Summary: The study shows that sea ice-air interactions are crucial for multidecadal climate variability in both the Arctic and North Atlantic. By amplifying multidecadal variations in sea-ice cover, sea surface temperatures, and surface air temperature, sea ice-air interactions mainly affect the Atlantic Meridional Overturning Circulation through changes in surface fluxes.
NATURE COMMUNICATIONS
(2022)
Article
Oceanography
Dylan Oldenburg, Robert C. J. Wills, Kyle C. Armour, LuAnne Thompson
Summary: The high-resolution simulations more accurately reproduce subpolar North Atlantic water mass transformation compared to the low-resolution simulations, which have larger biases. Despite these differences, the mechanisms of low-frequency AMOC variability are similar in both high- and low-resolution versions.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Meteorology & Atmospheric Sciences
Adrien Deroubaix, Guy Brasseur, Benjamin Gaubert, Inga Labuhn, Laurent Menut, Guillaume Siour, Paolo Tuccella
Summary: The lockdown period during the COVID-19 pandemic in Europe resulted in a reduction in anthropogenic emissions of primary pollutants, leading to a decrease in nitrogen dioxide concentrations. Ozone response varied spatially, with increases in Northern Europe and decreases in Southwestern Europe. The level of total oxidant remained unchanged in Northern Europe but decreased in Southwestern Europe.
METEOROLOGICAL APPLICATIONS
(2021)
Article
Environmental Sciences
Henda Guermazi, Pasquale Sellitto, Juan Cuesta, Maxim Eremenko, Mathieu Lachatre, Sylvain Mailler, Elisa Carboni, Giuseppe Salerno, Tommaso Caltabiano, Laurent Menut, Mohamed Moncef Serbaji, Farhat Rekhiss, Bernard Legras
Summary: A new retrieval algorithm called AEROIASI-H2SO4 was developed to measure the extinction and mass concentration of sulphate aerosols based on IASI observations. The algorithm shows moderate random uncertainties and accurately identifies the volcanic plume horizontal morphology, providing crucial new information towards the study of volcanic emissions. Insights are given on the possible spectroscopic evidence of the presence of larger-sized particles in the plume.
Article
Multidisciplinary Sciences
Shubha Verma, Sanhita Ghosh, Olivier Boucher, Rong Wang, Laurent Menut
Summary: This study evaluates the impact of black carbon (BC) on population exposure, morbidity, and mortality in the Indo-Gangetic plain. The results show a significant population exposure to BC, with more than 60 million people living in high-concentration areas. In terms of cardiovascular disease mortality, 62% of the burden is attributable to BC exposure in the megacity and 49% in the semiurban area. By implementing emission reduction strategies, over 400,000 lives can potentially be saved from cardiovascular disease mortality annually.
Article
Environmental Sciences
Arineh Cholakian, Bertrand Bessagnet, Laurent Menut, Romain Pennel, Sylvain Mailler
Summary: A set of simulations using the WRF and CHIMERE models were performed in the FAIRMODE initiative to study a PM pollution episode in Paris in February 2015. The simulation was validated and showed good agreement between measurements and the model. Major contributors to PM concentration were nitrates, organic aerosols, and ammonium. Different emission reduction scenarios were analyzed and it was found that even a severe reduction of 50% emissions would not eliminate PM exceedances. The impact of PM concentrations on radiative and thermodynamic budgets was also quantified.
Article
Meteorology & Atmospheric Sciences
Laurent Menut, Guillaume Siour, Bertrand Bessagnet, Arineh Cholakian, Romain Pennel, Sylvain Mailler
Summary: Mineral dust emissions are mainly affected by soil erodibility and near-surface wind speeds. During biomass burning, high surface wind speeds caused by pyroconvection and the replacement of non-desert surfaces with barren soil can contribute to additional mineral dust emissions. However, current chemistry-transport models often treat biomass burning and mineral dust emissions as independent processes, leading to an underestimation of mineral dust emissions and transported concentrations. This study adds the link between these emission processes in the CHIMERE chemistry-transport model and finds that it has a significant but not highly important effect on the whole meteorological and chemical system. It highlights the need to consider this link in future modeling.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Geosciences, Multidisciplinary
Laurent Menut
Summary: As part of the CADDIWA field campaign, the WRF-CHIMERE model was used to simulate dust emissions and transport in the Cape Verde area. The study analyzed the forecast variability of meteorological variables and mineral dust concentrations over a four-day period. It was found that the forecast quality remained consistent over time, and the variability of certain variables did not fully explain the behavior of other dependent variables. Additionally, a new ensemble forecast method was tested and showed improved results compared to available observations.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2023)
Article
Environmental Sciences
Danny M. Leung, Jasper F. Kok, Longlei Li, Gregory S. Okin, Catherine Prigent, Martina Klose, Carlos Perez Garcia-Pando, Laurent Menut, Natalie M. Mahowald, David M. Lawrence, Marcelo Chamecki
Summary: Desert dust is a major component of the atmosphere's aerosol burden and has significant impacts on the Earth system. However, current global climate models and land-surface models struggle to accurately represent dust emission processes due to inadequate representations of soil particle sizes, surface roughness elements, and boundary-layer characteristics. In this study, we address these issues by developing improved descriptions of these factors and propose a methodology to rescale lower-resolution dust emission simulations. Our revised dust emission parameterization shows substantial improvement in simulating dust emissions in both models.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Geosciences, Multidisciplinary
Sylvain Mailler, Laurent Menut, Arineh Cholakian, Romain Pennel
Summary: This study presents AerSett v1.0, a model that directly calculates the settling speed of large spherical aerosols in the atmosphere without iterative equation resolution. The results show that this simplified method, incorporating drag coefficient formulation and slip correction factor, produces results within 2% of the exact solution obtained from numerical resolution. The introduced Fortran implementation of this model aims to facilitate the inclusion of large-particle drag correction in chemistry-transport models and general circulation models, without the need for time-consuming iterative calculations.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2023)
Article
Environmental Sciences
Remy Lapere, Nicolas Huneeus, Sylvain Mailler, Laurent Menut, Florian Couvidat
Summary: Air pollution in the central zone of Chile, particularly the deposition of black carbon on glaciers of the Andes, has serious implications for public health, water resources, and climate. This study reveals a seasonal difference in the flux and latitudinal pattern of black carbon deposition, with higher deposition in winter affecting low-elevation glaciers and more even deposition in summer. The city of Santiago is a major contributor to summer emissions, while other sources contribute more during winter.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2023)
Article
Environmental Sciences
Mathieu Lachatre, Sylvain Mailler, Laurent Menut, Arineh Cholakian, Pasquale Sellitto, Guillaume Siour, Henda Guermazi, Giuseppe Salerno, Salvatore Giammanco
Summary: Volcanic activity is an important source of atmospheric sulfur dioxide (SO2), which can have various impacts on the environment. This study focuses on the conversion of SO2 into sulfates in the volcanic plume emitted by the explosive eruption of Mount Etna. The researchers used a chemistry transport model to investigate the sensitivity of SO2 oxidation to different parameters and found that both gaseous and aqueous oxidation processes contribute to sulfate production in the mid-troposphere.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Juan Cuesta, Lorenzo Costantino, Matthias Beekmann, Guillaume Siour, Laurent Menut, Bertrand Bessagnet, Tony C. Landi, Gaelle Dufour, Maxim Eremenko
Summary: This study integrates satellite observations, in situ measurements, and model simulations to assess the impact of anthropogenic emission reductions during the COVID-19 lockdown on ozone pollution in Europe. The results show that near-surface ozone increased in central Europe and northern Italy, while it decreased in other regions during the lockdown. The satellite and in situ observations, adjusted for meteorological conditions, provide consistent estimates of the ozone changes. However, the model simulations underestimate the magnitude of ozone changes compared to the observations.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Adrien Deroubaix, Laurent Menut, Cyrille Flamant, Peter Knippertz, Andreas H. Fink, Anneke Batenburg, Joel Brito, Cyrielle Denjean, Cheikh Dione, Regis Dupuy, Valerian Hahn, Norbert Kalthoff, Fabienne Lohou, Alfons Schwarzenboeck, Guillaume Siour, Paolo Tuccella, Christiane Voigt
Summary: This study evaluates the impact of anthropogenic aerosols on low-level clouds and precipitation during the West African summer monsoon using the WRF-CHIMERE model and observations from the DACCIWA field campaign. The results show that increased anthropogenic aerosol emissions delay the breakup time of low-level clouds, decrease daily precipitation rates, and have a more significant effect on low-level cloud cover during specific time periods.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Sanhita Ghosh, Shubha Verma, Jayanarayanan Kuttippurath, Laurent Menut
Summary: Improving the prediction of modelled BC distribution, particularly in regions with high BC concentration like the Indo-Gangetic Plain, is crucial for reducing uncertainty in global and regional aerosol-climate model simulations. Simulations using observational constrained BC emissions showed more efficient distribution of BC pollution over the Indo-Gangetic Plain, with significant impacts on major cities in India.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
Sylvain Mailler, Romain Pennel, Laurent Menut, Mathieu Lachatre
Summary: The antidiffusive transport scheme proposed by Despres and Lagoutiere (1999) shows great potential for reducing numerical diffusion and improving accuracy in vertical transport in chemistry-transport models, particularly when vertical resolution is insufficient.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2021)
Article
Environmental Sciences
Remy Lapere, Laurent Menut, Sylvain Mailler, Nicolas Huneeus
Summary: Central Chile experiences year-round atmospheric pollution issues due to high concentrations of fine particulate matter and tropospheric ozone. The region faces challenges related to public health, vegetation growth, water supply, and meteorological feedback. With complex geographical factors and sharp spatial gradients in emissions, the localization and transport of pollutants exhibit variability and seasonal differences.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
