241 results on '"Paulot, Fabien"'
Search Results
2. Sensitivity of Tropospheric Ozone Over the Southeast USA to Dry Deposition
- Author
-
Baublitz, Colleen B, Fiore, Arlene M, Clifton, Olivia E, Mao, Jingqiu, Li, Jingyi, Correa, Gus, Westervelt, Daniel M, Horowitz, Larry W, Paulot, Fabien, and Williams, A Park
- Subjects
Climate Action ,Meteorology & Atmospheric Sciences - Published
- 2020
3. Climate benefit of a future hydrogen economy
- Author
-
Hauglustaine, Didier, Paulot, Fabien, Collins, William, Derwent, Richard, Sand, Maria, and Boucher, Olivier
- Published
- 2022
- Full Text
- View/download PDF
4. Risk of the hydrogen economy for atmospheric methane
- Author
-
Bertagni, Matteo B., Pacala, Stephen W., Paulot, Fabien, and Porporato, Amilcare
- Published
- 2022
- Full Text
- View/download PDF
5. The GFDL Variable‐Resolution Global Chemistry‐Climate Model for Research at the Nexus of US Climate and Air Quality Extremes
- Author
-
Lin, Meiyun, primary, Horowitz, Larry W., additional, Zhao, Ming, additional, Harris, Lucas, additional, Ginoux, Paul, additional, Dunne, John, additional, Malyshev, Sergey, additional, Shevliakova, Elena, additional, Ahsan, Hamza, additional, Garner, Steve, additional, Paulot, Fabien, additional, Pouyaei, Arman, additional, Smith, Steven J., additional, Xie, Yuanyu, additional, Zadeh, Niki, additional, and Zhou, Linjiong, additional
- Published
- 2024
- Full Text
- View/download PDF
6. Global modeling of hydrogen using GFDL-AM4.1: Sensitivity of soil removal and radiative forcing
- Author
-
Paulot, Fabien, Paynter, David, Naik, Vaishali, Malyshev, Sergey, Menzel, Raymond, and Horowitz, Larry W.
- Published
- 2021
- Full Text
- View/download PDF
7. Database of nitrification and nitrifiers in the global ocean
- Author
-
Tang, Weiyi, primary, Ward, Bess B., additional, Beman, Michael, additional, Bristow, Laura, additional, Clark, Darren, additional, Fawcett, Sarah, additional, Frey, Claudia, additional, Fripiat, François, additional, Herndl, Gerhard J., additional, Mdutyana, Mhlangabezi, additional, Paulot, Fabien, additional, Peng, Xuefeng, additional, Santoro, Alyson E., additional, Shiozaki, Takuhei, additional, Sintes, Eva, additional, Stock, Charles, additional, Sun, Xin, additional, Wan, Xianhui S., additional, Xu, Min N., additional, and Zhang, Yao, additional
- Published
- 2023
- Full Text
- View/download PDF
8. Chemical transport models often underestimate inorganic aerosol acidity in remote regions of the atmosphere
- Author
-
Nault, Benjamin A., Campuzano-Jost, Pedro, Day, Douglas A., Jo, Duseong S., Schroder, Jason C., Allen, Hannah M., Bahreini, Roya, Bian, Huisheng, Blake, Donald R., Chin, Mian, Clegg, Simon L., Colarco, Peter R., Crounse, John D., Cubison, Michael J., DeCarlo, Peter F., Dibb, Jack E., Diskin, Glenn S., Hodzic, Alma, Hu, Weiwei, Katich, Joseph M., Kim, Michelle J., Kodros, John K., Kupc, Agnieszka, Lopez-Hilfiker, Felipe D., Marais, Eloise A., Middlebrook, Ann M., Andrew Neuman, J., Nowak, John B., Palm, Brett B., Paulot, Fabien, Pierce, Jeffrey R., Schill, Gregory P., Scheuer, Eric, Thornton, Joel A., Tsigaridis, Kostas, Wennberg, Paul O., Williamson, Christina J., and Jimenez, Jose L.
- Published
- 2021
- Full Text
- View/download PDF
9. Vegetation feedbacks during drought exacerbate ozone air pollution extremes in Europe
- Author
-
Lin, Meiyun, Horowitz, Larry W., Xie, Yuanyu, Paulot, Fabien, Malyshev, Sergey, Shevliakova, Elena, Finco, Angelo, Gerosa, Giacomo, Kubistin, Dagmar, and Pilegaard, Kim
- Published
- 2020
- Full Text
- View/download PDF
10. Rapid deposition of oxidized biogenic compounds to a temperate forest
- Author
-
Nguyen, Tran B, Crounse, John D, Teng, Alex P, St Clair, Jason M, Paulot, Fabien, Wolfe, Glenn M, and Wennberg, Paul O
- Subjects
Air Pollutants ,Forests ,Oxidation-Reduction ,biosphere-atmosphere exchange ,isoprene ,dry deposition ,OVOCs ,fluxes - Abstract
We report fluxes and dry deposition velocities for 16 atmospheric compounds above a southeastern United States forest, including: hydrogen peroxide (H2O2 ), nitric acid (HNO3), hydrogen cyanide (HCN), hydroxymethyl hydroperoxide, peroxyacetic acid, organic hydroxy nitrates, and other multifunctional species derived from the oxidation of isoprene and monoterpenes. The data suggest that dry deposition is the dominant daytime sink for small, saturated oxygenates. Greater than 6 wt %C emitted as isoprene by the forest was returned by dry deposition of its oxidized products. Peroxides account for a large fraction of the oxidant flux, possibly eclipsing ozone in more pristine regions. The measured organic nitrates comprise a sizable portion (15%) of the oxidized nitrogen input into the canopy, with HNO3 making up the balance. We observe that water-soluble compounds (e.g., strong acids and hydroperoxides) deposit with low surface resistance whereas compounds with moderate solubility (e.g., organic nitrates and hydroxycarbonyls) or poor solubility (e.g., HCN) exhibited reduced uptake at the surface of plants. To first order, the relative deposition velocities of water-soluble compounds are constrained by their molecular diffusivity. From resistance modeling, we infer a substantial emission flux of formic acid at the canopy level (∼1 nmol m-2•s-1). GEOS-Chem, awidely used atmospheric chemical transport model, currently underestimates dry deposition for most molecules studied in this work. Reconciling GEOS -Chem deposition velocities with observations resulted in up to a 45% decrease in the simulated surface concentration of trace gases.
- Published
- 2015
11. Air quality impacts from the electrification of light-duty passenger vehicles in the United States
- Author
-
Schnell, Jordan L., Naik, Vaishali, Horowitz, Larry W., Paulot, Fabien, Ginoux, Paul, Zhao, Ming, and Horton, Daniel E.
- Published
- 2019
- Full Text
- View/download PDF
12. Reanalysis of NOAA H2 observations: implications for the H2 budget.
- Author
-
Paulot, Fabien, Pétron, Gabrielle, Crotwell, Andrew M., and Bertagni, Matteo B.
- Subjects
SNOW cover ,ALTERNATIVE fuels ,MOLE fraction ,SOIL temperature ,AIR sampling ,SNOW removal - Abstract
Hydrogen (H2) is a promising low-carbon alternative to fossil fuels for many applications. However, significant gaps in our understanding of the atmospheric H2 budget limit our ability to predict the impacts of greater H2 usage. Here we use NOAA H 2 dry air mole fraction observations from air samples collected from ground-based and ship platforms during 2010–2019 to evaluate the representation of H 2 in the NOAA GFDL-AM4.1 atmospheric chemistry-climate model. We find that the base model configuration captures the observed interhemispheric gradient well but underestimates the surface concentration of H2 by about 10 ppb. Additionally, the model fails to reproduce the 1–2 ppb yr -1 mean increase in surface H 2 observed at background stations. We show that the cause is most likely an underestimation of current anthropogenic emissions, including potential leakages from H 2 -producing facilities. We also show that changes in soil moisture, soil temperature, and snow cover have most likely caused an increase in the magnitude of the soil sink, the most important removal mechanism for atmospheric H2 , especially in the Northern Hemisphere. However, there remains uncertainty due to fundamental gaps in our understanding of H 2 soil removal, such as the minimum moisture required for H 2 soil uptake, for which we performed extensive sensitivity analyses. Finally, we show that the observed meridional gradient of the H2 mixing ratio and its seasonality can provide important constraints to test and refine parameterizations of the H2 soil sink. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
13. US SOLAS Science Report
- Author
-
Stanley, Rachel H. R., primary, Thomas, Thomas, additional, Gao, Yuan, additional, Gaston, Cassandra, additional, Ho, David, additional, Kieber, David, additional, Mackey, Kate, additional, Meskhidze, Nicholas, additional, Miller, William L., additional, Potter, Henry, additional, Vlahos, Penny, additional, Yager, Patricia, additional, Alexander, Becky, additional, Beaupre, Steven R., additional, Craig, Susanne, additional, Cutter, Greg, additional, Emerson, Steven, additional, Frossard, Amanda A., additional, Gasso, Santiago, additional, Haus, Brian, additional, Keene, William C., additional, Landing, William M., additional, Moore, Richard H., additional, Ortiz-Suslow, David, additional, Palter, Jaime, additional, Paulot, Fabien, additional, Saltzman, Eric, additional, Thornton, Daniel, additional, Wozniak, Andrew, additional, Zamora, Lauren, additional, and Benway, Heather, additional
- Published
- 2021
- Full Text
- View/download PDF
14. Top‐down isoprene emissions over tropical South America inferred from SCIAMACHY and OMI formaldehyde columns
- Author
-
Barkley, Michael P, De Smedt, Isabelle, Van Roozendael, Michel, Kurosu, Thomas P, Chance, Kelly, Arneth, Almut, Hagberg, Daniel, Guenther, Alex, Paulot, Fabien, Marais, Eloise, and Mao, Jingqiu
- Subjects
Climate Action ,Amazon ,isoprene ,formaldehyde ,SCIAMACHY ,OMI ,GEOS-Chem ,Atmospheric Sciences ,Physical Geography and Environmental Geoscience - Abstract
We use formaldehyde (HCHO) vertical column measurements from the Scanning Imaging Absorption spectrometer for Atmospheric Chartography (SCIAMACHY) and Ozone Monitoring Instrument (OMI), and a nested-grid version of the GEOS-Chem chemistry transport model, to infer an ensemble of top-down isoprene emission estimates from tropical South America during 2006, using different model configurations and assumptions in the HCHO air-mass factor (AMF) calculation. Scenes affected by biomass burning are removed on a daily basis using fire count observations, and we use the local model sensitivity to identify locations where the impact of spatial smearing is small, though this comprises spatial coverage over the region. We find that the use of the HCHO column data more tightly constrains the ensemble isoprene emission range from 27-61 Tg C to 31-38 Tg C for SCIAMACHY, and 45-104 Tg C to 28-38 Tg C for OMI. Median uncertainties of the top-down emissions are about 60-260% for SCIAMACHY, and 10-90% for OMI. We find that the inferred emissions are most sensitive to uncertainties in cloud fraction and cloud top pressure (differences of ±10%), the a priori isoprene emissions (±20%), and the HCHO vertical column retrieval (±30%). Construction of continuous top-down emission maps generally improves GEOS-Chem's simulation of HCHO columns over the region, with respect to both the SCIAMACHY and OMI data. However, if local time top-down emissions are scaled to monthly mean values, the annual emission inferred from SCIAMACHY are nearly twice those from OMI. This difference cannot be explained by the different sampling of the sensors or uncertainties in the AMF calculation. Key Points Satellite HCHO data constrain range of uncertainty in Amazon isoprene emissions Top-down emissions are sensitive to prior isoprene inventory and HCHO retrieval Top-down emissions from SCIAMACHY are about twice those derived from OMI © 2013. American Geophysical Union. All Rights Reserved.
- Published
- 2013
15. Can a “state of the art” chemistry transport model simulate Amazonian tropospheric chemistry?
- Author
-
Barkley, Michael P, Palmer, Paul I, Ganzeveld, Laurens, Arneth, Almut, Hagberg, Daniel, Karl, Thomas, Guenther, Alex, Paulot, Fabien, Wennberg, Paul O, Mao, Jingqiu, Kurosu, Thomas P, Chance, Kelly, Müller, J‐F, De Smedt, Isabelle, Van Roozendael, Michel, Chen, Dan, Wang, Yuxuan, and Yantosca, Robert M
- Subjects
Earth Sciences ,Atmospheric Sciences ,Climate Action ,Meteorology & Atmospheric Sciences - Abstract
We present an evaluation of a nested high-resolution Goddard Earth Observing System (GEOS)-Chem chemistry transport model simulation of tropospheric chemistry over tropical South America. The model has been constrained with two isoprene emission inventories: (1) the canopy-scale Model of Emissions of Gases and Aerosols from Nature (MEGAN) and (2) a leaf-scale algorithm coupled to the Lund-Potsdam-Jena General Ecosystem Simulator (LPJ-GUESS) dynamic vegetation model, and the model has been run using two different chemical mechanisms that contain alternative treatments of isoprene photo-oxidation. Large differences of up to 100 Tg C yr-1 exist between the isoprene emissions predicted by each inventory, with MEGAN emissions generally higher. Based on our simulations we estimate that tropical South America (30-85°W, 14°N-25°S) contributes about 15-35% of total global isoprene emissions. We have quantified the model sensitivity to changes in isoprene emissions, chemistry, boundary layer mixing, and soil NOx emissions using ground-based and airborne observations. We find GEOS-Chem has difficulty reproducing several observed chemical species; typically hydroxyl concentrations are underestimated, whilst mixing ratios of isoprene and its oxidation products are overestimated. The magnitude of model formaldehyde (HCHO) columns are most sensitive to the choice of chemical mechanism and isoprene emission inventory. We find GEOS-Chem exhibits a significant positive bias (10-100%) when compared with HCHO columns from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) and Ozone Monitoring Instrument (OMI) for the study year 2006. Simulations that use the more detailed chemical mechanism and/or lowest isoprene emissions provide the best agreement to the satellite data, since they result in lower-HCHO columns. Copyright © 2011 by the American Geophysical Union.
- Published
- 2011
16. A multi-model assessment of the Global Warming Potential of hydrogen
- Author
-
Sand, Maria, primary, Skeie, Ragnhild Bieltvedt, additional, Sandstad, Marit, additional, Krishnan, Srinath, additional, Myhre, Gunnar, additional, Bryant, Hannah, additional, Derwent, Richard, additional, Hauglustaine, Didier, additional, Paulot, Fabien, additional, Prather, Michael, additional, and Stevenson, David, additional
- Published
- 2023
- Full Text
- View/download PDF
17. Volcanic Drivers of Stratospheric Sulfur in GFDL ESM4
- Author
-
Gao, Chloe Yuchao, primary, Naik, Vaishali, additional, Horowitz, Larry W., additional, Ginoux, Paul, additional, Paulot, Fabien, additional, Dunne, John, additional, Mills, Michael, additional, Aquila, Valentina, additional, and Colarco, Peter, additional
- Published
- 2023
- Full Text
- View/download PDF
18. Reanalysis of NOAA H2 observations: implications for the H2 budget
- Author
-
Paulot, Fabien, Pétron, Gabrielle, Crotwell, Andrew M., and Bertagni, Matteo B.
- Abstract
Hydrogen (H2) is being considered for many applications as an alternative to fossil fuels. Robust assessment of the climate implications of increased H2 usage in the global economy is partly hindered by uncertainties in its biogeochemical cycle. Here we use NOAA H2 dry air mole fraction observations from air samples collected from ground-based and ship platforms from 2010 to 2019 to evaluate the representation of H2 in the NOAA GFDL-AM4.1 atmospheric chemistry-climate model. We find that the model captures the observed interhemispheric gradient well but underestimates the surface concentration of H2 by about 10 ppbv. Observations show a 1–2 ppbv/year mean increase in surface H2 at background stations, while the simulated H2 exhibits no significant change over the 2010–2019 period. We show that this model bias is primarily driven by the estimated decrease of anthropogenic emissions, mostly from transportation, and that including leakage from H2-producing facilities can improve the simulated trend. We find that changes in soil moisture, soil temperature, and snow cover likely increase the magnitude and modify spatial distribution of the soil sink, the most important removal mechanism for atmospheric H2. However, the magnitude and even the sign of such changes is uncertain due to fundamental gaps in our understanding of H2 soil removal, such as the minimum soil moisture for H2 soil uptake. We show that the observed meridional gradient of H2 mixing ratio and its seasonality provide important constraints to test and refine parameterizations of H2 soil removal.
- Published
- 2023
19. Database of nitrification and nitrifiers in the global ocean
- Author
-
Tang, Weiyi, Ward, Bess B., Beman, Michael, Bristow, Laura, Clark, Darren, Fawcett, Sarah E., Frey, Claudia, Fripiat, François, Herndl, Gerhard, Mdutyana, Mhlangabezi, Paulot, Fabien, Peng, Xuefeng, Santoro, Alyson E., Shiozaki, Takuhei, Sintes, Eva, Stock, Charles, Sun, Xin, Wan, Xianhui S., Xu, Min N., Zhang, Yao, Tang, Weiyi, Ward, Bess B., Beman, Michael, Bristow, Laura, Clark, Darren, Fawcett, Sarah E., Frey, Claudia, Fripiat, François, Herndl, Gerhard, Mdutyana, Mhlangabezi, Paulot, Fabien, Peng, Xuefeng, Santoro, Alyson E., Shiozaki, Takuhei, Sintes, Eva, Stock, Charles, Sun, Xin, Wan, Xianhui S., Xu, Min N., and Zhang, Yao
- Abstract
As a key biogeochemical pathway in the marine nitrogen cycle, nitrification (ammonia oxidation and nitrite oxidation) converts the most reduced form of nitrogen – ammonium–ammonia (NH4+–NH3) – into the oxidized species nitrite (NO2-) and nitrate (NO3-). In the ocean, these processes are mainly performed by ammonia-oxidizing archaea (AOA) and bacteria (AOB) and nitrite-oxidizing bacteria (NOB). By transforming nitrogen speciation and providing substrates for nitrogen removal, nitrification affects microbial community structure; marine productivity (including chemoautotrophic carbon fixation); and the production of a powerful greenhouse gas, nitrous oxide (N2O). Nitrification is hypothesized to be regulated by temperature, oxygen, light, substrate concentration, substrate flux, pH and other environmental factors. Although the number of field observations from various oceanic regions has increased considerably over the last few decades, a global synthesis is lacking, and understanding how environmental factors control nitrification remains elusive. Therefore, we have compiled a database of nitrification rates and nitrifier abundance in the global ocean from published literature and unpublished datasets. This database includes 2393 and 1006 measurements of ammonia oxidation and nitrite oxidation rates and 2242 and 631 quantifications of ammonia oxidizers and nitrite oxidizers, respectively. This community effort confirms and enhances our understanding of the spatial distribution of nitrification and nitrifiers and their corresponding drivers such as the important role of substrate concentration in controlling nitrification rates and nitrifier abundance. Some conundrums are also revealed, including the inconsistent observations of light limitation and high rates of nitrite oxidation reported from anoxic waters. This database can be used to constrain the distribution of marine nitrification, to evaluate and improve biogeochemical models of nitrification, and to, info:eu-repo/semantics/published
- Published
- 2023
20. Database of nitrification and nitrifiers in the global ocean
- Author
-
Cooperative Institute for Modeling the Earth System (US), Tang, Weiyi, Ward, Bess B., Beman, Michael, Bristow, Laura, Clark, Darren, Fawcett, Sarah, Frey, Claudia, Fripiat, François, Herndl, Gerhard J., Mdutyana, Mhlangabezi, Paulot, Fabien, Peng, Xuefeng, Santoro, Alyson E., Shiozaki, Takuhei, Sintes, Eva, Stock, Charles, Sun, Xin, Wan, Xianhui S., Xu, Min N., Zhang, Yao, Cooperative Institute for Modeling the Earth System (US), Tang, Weiyi, Ward, Bess B., Beman, Michael, Bristow, Laura, Clark, Darren, Fawcett, Sarah, Frey, Claudia, Fripiat, François, Herndl, Gerhard J., Mdutyana, Mhlangabezi, Paulot, Fabien, Peng, Xuefeng, Santoro, Alyson E., Shiozaki, Takuhei, Sintes, Eva, Stock, Charles, Sun, Xin, Wan, Xianhui S., Xu, Min N., and Zhang, Yao
- Abstract
As a key biogeochemical pathway in the marine nitrogen cycle, nitrification (ammonia oxidation and nitrite oxidation) converts the most reduced form of nitrogen-ammonium-Ammonia (NH4+-NH3)-into the oxidized species nitrite (NO2-) and nitrate (NO3-). In the ocean, these processes are mainly performed by ammonia-oxidizing archaea (AOA) and bacteria (AOB) and nitrite-oxidizing bacteria (NOB). By transforming nitrogen speciation and providing substrates for nitrogen removal, nitrification affects microbial community structure; marine productivity (including chemoautotrophic carbon fixation); and the production of a powerful greenhouse gas, nitrous oxide (N2O). Nitrification is hypothesized to be regulated by temperature, oxygen, light, substrate concentration, substrate flux, pH and other environmental factors. Although the number of field observations from various oceanic regions has increased considerably over the last few decades, a global synthesis is lacking, and understanding how environmental factors control nitrification remains elusive. Therefore, we have compiled a database of nitrification rates and nitrifier abundance in the global ocean from published literature and unpublished datasets. This database includes 2393 and 1006 measurements of ammonia oxidation and nitrite oxidation rates and 2242 and 631 quantifications of ammonia oxidizers and nitrite oxidizers, respectively. This community effort confirms and enhances our understanding of the spatial distribution of nitrification and nitrifiers and their corresponding drivers such as the important role of substrate concentration in controlling nitrification rates and nitrifier abundance. Some conundrums are also revealed, including the inconsistent observations of light limitation and high rates of nitrite oxidation reported from anoxic waters. This database can be used to constrain the distribution of marine nitrification, to evaluate and improve biogeochemical models of nitrification, and to quantify the i
- Published
- 2023
21. Attribution of the ozone band radiative flux bias in Chemistry-Climate Model Initiative (CCMI) models from satellites
- Author
-
Kunze, Markus, Jöckel, Patrick, Shibata, Kiyotaka, Deushi, Makoto, Plummer, David, Revell, Laura, Stenke, Andrea, Rozanov, Eugene, Strode, Sarah, Oman, Luke, Paynter, David, Paulot, Fabien, Kulawik, Susan, Lamarque, Jean-François, Conley, Andrew, Worden, Helen, Miyazaki, Kazuyuki, Bowman, Kevin W, and Kuai, Le
- Abstract
UNKNOWN
- Published
- 2019
22. Attribution of the ozone band radiative flux bias in Chemistry-Climate Model Initiative (CCMI) models from satellites
- Author
-
Kuai, Le, Bowman, Kevin W, Miyazaki, Kazuyuki, Worden, Helen, Conley, Andrew, Lamarque, Jean-François, Kulawik, Susan, Paulot, Fabien, Paynter, David, Oman, Luke, Strode, Sarah, Rozanov, Eugene, Stenke, Andrea, Revell, Laura, Plummer, David, Deushi, Makoto, Shibata, Kiyotaka, Jöckel, Patrick, and Kunze, Markus
- Published
- 2019
23. Attribution of the ozone band radiative flux bias in Chemistry-Climate Model Initiative (CCMI) models from satellites
- Author
-
Kulawik, Susan, Kunze, Markus, Jöckel, Patrick, Shibata, Kiyotaka, Deushi, Makoto, Plummer, David, Revell, Laura, Stenke, Andrea, Rozanov, Eugene, Strode, Sarah, Oman, Luke, Paynter, David, Paulot, Fabien, Lamarque, Jean-François, Conley, Andrew, Miyazaki, Kazuyuki, Worden, Helen, Bowman, Kevin W, and Kuai, Le
- Abstract
UNKNOWN
- Published
- 2019
24. Publisher Correction: Vegetation feedbacks during drought exacerbate ozone air pollution extremes in Europe
- Author
-
Lin, Meiyun, Horowitz, Larry W., Xie, Yuanyu, Paulot, Fabien, Malyshev, Sergey, Shevliakova, Elena, Finco, Angelo, Gerosa, Giacomo, Kubistin, Dagmar, and Pilegaard, Kim
- Published
- 2020
- Full Text
- View/download PDF
25. Robust evidence for reversal of the trend in aerosol effective climate forcing
- Author
-
Quaas, Johannes, primary, Jia, Hailing, additional, Smith, Chris, additional, Albright, Anna Lea, additional, Aas, Wenche, additional, Bellouin, Nicolas, additional, Boucher, Olivier, additional, Doutriaux-Boucher, Marie, additional, Forster, Piers M., additional, Grosvenor, Daniel, additional, Jenkins, Stuart, additional, Klimont, Zbigniew, additional, Loeb, Norman G., additional, Ma, Xiaoyan, additional, Naik, Vaishali, additional, Paulot, Fabien, additional, Stier, Philip, additional, Wild, Martin, additional, Myhre, Gunnar, additional, and Schulz, Michael, additional
- Published
- 2022
- Full Text
- View/download PDF
26. Large sub-regional differences of ammonia seasonal patterns over India reveal inventory discrepancies
- Author
-
Beale, Christopher A, primary, Paulot, Fabien, additional, Randles, Cynthia A, additional, Wang, Rui, additional, Guo, Xuehui, additional, Clarisse, Lieven, additional, Van Damme, Martin, additional, Coheur, Pierre-François, additional, Clerbaux, Cathy, additional, Shephard, Mark W, additional, Dammers, Enrico, additional, Cady-Pereira, Karen, additional, and Zondlo, Mark A, additional
- Published
- 2022
- Full Text
- View/download PDF
27. Reduction in Near‐Surface Wind Speeds With Increasing CO2 May Worsen Winter Air Quality in the Indo‐Gangetic Plain
- Author
-
Paulot, Fabien, primary, Naik, Vaishali, additional, and W. Horowitz, Larry, additional
- Published
- 2022
- Full Text
- View/download PDF
28. Reanalysis of NOAA H2 observations: implications for the H2 budget.
- Author
-
Paulot, Fabien, Pétron, Gabrielle, Crotwell, Andrew M., and Bertagni, Matteo B.
- Subjects
SNOW cover ,BIOGEOCHEMICAL cycles ,ALTERNATIVE fuels ,MOLE fraction ,SOIL temperature ,SNOW accumulation ,CARBONACEOUS aerosols - Abstract
Hydrogen (H
2 ) is being considered for many applications as an alternative to fossil fuels. Robust assessment of the climate implications of increased H2 usage in the global economy is partly hindered by uncertainties in its biogeochemical cycle. Here we use NOAA H2 dry air mole fraction observations from air samples collected from ground-based and ship platforms from 2010 to 2019 to evaluate the representation of H2 in the NOAA GFDL-AM4.1 atmospheric chemistry-climate model. We find that the model captures the observed interhemispheric gradient well but underestimates the surface concentration of H2 by about 10 ppbv. Observations show a 1–2 ppbv/year mean increase in surface H2 at background stations, while the simulated H2 exhibits no significant change over the 2010–2019 period. We show that this model bias is primarily driven by the estimated decrease of anthropogenic emissions, mostly from transportation, and that including leakage from H2 -producing facilities can improve the simulated trend. We find that changes in soil moisture, soil temperature, and snow cover likely increase the magnitude and modify spatial distribution of the soil sink, the most important removal mechanism for atmospheric H2 . However, the magnitude and even the sign of such changes is uncertain due to fundamental gaps in our understanding of H2 soil removal, such as the minimum soil moisture for H2 soil uptake. We show that the observed meridional gradient of H2 mixing ratio and its seasonality provide important constraints to test and refine parameterizations of H2 soil removal. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
29. Database of nitrification and nitrifiers in the global ocean.
- Author
-
Weiyi Tang, Ward, Bess B., Beman, Michael, Bristow, Laura, Clark, Darren, Fawcett, Sarah, Frey, Claudia, Fripiat, Francois, Herndl, Gerhard J., Mdutyana, Mhlangabezi, Paulot, Fabien, Xuefeng Peng, Santoro, Alyson E., Takuhei Shiozaki, Sintes, Eva, Stock, Charles, Xin Sun, Wan, Xianhui S., Xu, Min N., and Yao Zhang
- Subjects
NITRIFICATION ,DATABASES ,NITROGEN cycle ,ANOXIC waters ,MARINE productivity ,CARBON fixation - Abstract
As a key biogeochemical pathway in the marine nitrogen cycle, nitrification (ammonia oxidation and nitrite oxidation) converts the most reduced form of nitrogen - ammonium/ammonia (NH4+/NH3) into the oxidized species nitrite (NO2-) and nitrate (NO3-). In the ocean, these processes are mainly performed by ammonia-oxidizing archaea (AOA) and bacteria (AOB), and nitrite oxidizing bacteria (NOB). By transforming nitrogen speciation and providing substrates for nitrogen removal, nitrification affects microbial community structure, marine productivity (including chemoautotrophic carbon fixation) and the production of a powerful greenhouse gas, nitrous oxide (N2O). Nitrification is hypothesized to be regulated by temperature, oxygen, light, substrate concentration, substrate flux, pH, and other environmental factors. Although the number of field observations from various oceanic regions has increased considerably over the last few decades, a global synthesis is lacking, and understanding how environmental factors control nitrification remains elusive. Therefore, we have compiled a database of nitrification rates and nitrifier abundance in the global ocean from published literature and unpublished datasets. This database includes 2393 and 1006 measurements of ammonia oxidation and nitrite oxidation rates, and 2187 and 631 quantifications of ammonia oxidizers and nitrite oxidizers, respectively. This community effort confirms and enhances our understanding of the spatial distribution of nitrification and nitrifiers, and their corresponding drivers such as the important role of substrate concentration in controlling nitrification rates and nitrifier abundance. Some conundrums are also revealed including the inconsistent observations of light limitation and high rates of nitrite oxidation reported from anoxic waters. This database can be used to constrain the distribution of marine nitrification, to evaluate and improve biogeochemical models of nitrification, and to quantify the impact of nitrification on ecosystem functions like marine productivity and N2O production. This database additionally sets a baseline for comparison with future observations and guides future exploration (e.g., measurements in the poorly sampled regions such as the Indian Ocean; method comparison/standardization). The database is publicly available at Zenodo repository: https://doi.org/10.5281/zenodo.7942922 (Tang et al., 2023). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. Decadal Changes in Summertime Reactive Oxidized Nitrogen and Surface Ozone over the Southeast United States
- Author
-
Li, Jingyi, Mao, Jingqiu, Fiore, Arlene M, Cohen, Ronald C, Crounse, John D, Teng, Alex P, Wennberg, Paul O, Lee, Ben H, Lopez-Hilfiker, Felipe D, Thornton, Joel A, Peischl, Jeff, Pollack, Ilana B, Ryerson, Thomas B, Veres, Patrick, Roberts, James M, Neuman, J. Andrew, Nowak, John B, Wolfe, Glenn M, Hanisco, Thomas F, Fried, Alan, Singh, Hanwant B, Dibb, Jack, Paulot, Fabien, and Horowitz, Larry W
- Subjects
Environment Pollution - Abstract
Widespread efforts to abate ozone (O3) smog have significantly reduced emissions of nitrogen oxides (NOx) over the past 2 decades in the Southeast US, a place heavily influenced by both anthropogenic and biogenic emissions. How reactive nitrogen speciation responds to the reduction in NOx emissions in this region remains to be elucidated. Here we exploit aircraft measurements from ICARTT (International Consortium for Atmospheric Research on Transport and Transformation - July-August 2004), SENEX (Southeast Nexus - June-July 2013), and SEAC4RS (Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys - August-September 2013) and long-term ground measurement networks alongside a global chemistry-climate model to examine decadal changes in summertime reactive oxidized nitrogen (RON) and ozone over the Southeast US. We show that our model can reproduce the mean vertical profiles of major RON species and the total (NO (sub y)) in both 2004 and 2013. Among the major RON species, nitric acid (HNO3) is dominant (approximately 42-45 percent), followed by NOx (31 percent), total peroxy nitrates (Sigma PNs; 14 percent), and total alkyl nitrates (Sigma ANs; 9-12 percent) on a regional scale. We find that most RON species, including NOx, Sigma PNs, and HNO3, decline proportionally with decreasing NOx emissions in this region, leading to a similar decline in NO (sub y). This linear response might be in part due to the nearly constant summertime supply of biogenic VOC (Volatile Organic Compounds) emissions in this region. Our model captures the observed relative change in RON and surface ozone from 2004 to 2013. Model sensitivity tests indicate that further reductions of NOx emissions will lead to a continued decline in surface ozone and less frequent high-ozone events.
- Published
- 2018
- Full Text
- View/download PDF
31. Improving Estimates of Sulfur, Nitrogen, and Ozone Total Deposition through Multi-Model and Measurement-Model Fusion Approaches
- Author
-
Fu, Joshua S., Carmichael, Gregory R., Dentener, Frank, Aas, Wenche, Andersson, Camilla, Barrie, Leonard A., Cole, Amanda, Galy-Lacaux, Corinne, Geddes, Jeffrey, Itahashi, Syuichi, Kanakidou, Maria, Labrador, Lorenzo, Paulot, Fabien, Schwede, Donna, Tan, Jiani, Vet, Robert, Fu, Joshua S., Carmichael, Gregory R., Dentener, Frank, Aas, Wenche, Andersson, Camilla, Barrie, Leonard A., Cole, Amanda, Galy-Lacaux, Corinne, Geddes, Jeffrey, Itahashi, Syuichi, Kanakidou, Maria, Labrador, Lorenzo, Paulot, Fabien, Schwede, Donna, Tan, Jiani, and Vet, Robert
- Published
- 2022
- Full Text
- View/download PDF
32. Robust evidence for reversal of the trend in aerosol effective climate forcing
- Author
-
Quaas, Johannes, Jia, Hailing, Smith, Chris, Albright, Anna Lea, Aas, Wenche, Bellouin, Nicolas, Boucher, Olivier, Doutriaux-Boucher, Marie, Forster, Piers M., Grosvenor, Daniel, Jenkins, Stuart, Klimont, Zbigniew, Loeb, Norman G., Ma, Xiaoyan, Naik, Vaishali, Paulot, Fabien, Stier, Philip, Wild, Martin, Myhre, Gunnar, Schulz, Michael, Quaas, Johannes, Jia, Hailing, Smith, Chris, Albright, Anna Lea, Aas, Wenche, Bellouin, Nicolas, Boucher, Olivier, Doutriaux-Boucher, Marie, Forster, Piers M., Grosvenor, Daniel, Jenkins, Stuart, Klimont, Zbigniew, Loeb, Norman G., Ma, Xiaoyan, Naik, Vaishali, Paulot, Fabien, Stier, Philip, Wild, Martin, Myhre, Gunnar, and Schulz, Michael
- Abstract
Anthropogenic aerosols exert a cooling influence that offsets part of the greenhouse gas warming. Due to their short tropospheric lifetime of only several days, the aerosol forcing responds quickly to emissions. Here, we present and discuss the evolution of the aerosol forcing since 2000. There are multiple lines of evidence that allow us to robustly conclude that the anthropogenic aerosol effective radiative forcing (ERF) – both aerosol– radiation interactions (ERFari) and aerosol–cloud interactions (ERFaci) – has become less negative globally, i.e. the trend in aerosol effective radiative forcing changed sign from negative to positive. Bottom-up inventories show that anthropogenic primary aerosol and aerosol precursor emissions declined in most regions of the world; observations related to aerosol burden show declining trends, in particular of the fine-mode particles that make up most of the anthropogenic aerosols; satellite retrievals of cloud droplet numbers show trends in regions with aerosol declines that are consistent with these in sign, as do observations of top-of-atmosphere radiation. Climate model results, including a revised set that is constrained by observations of the ocean heat content evolution show a consistent sign and magnitude for a positive forcing relative to the year 2000 due to reduced aerosol effects. This reduction leads to an acceleration of the forcing of climate change, i.e. an increase in forcing by 0.1 to 0.3 W m−2 , up to 12 % of the total climate forcing in 2019 compared to 1750 according to the Intergovernmental Panel on Climate Change (IPCC).
- Published
- 2022
33. Large sub-regional differences of ammonia seasonal patterns over India reveal inventory discrepancies
- Author
-
Beale, Christopher, Paulot, Fabien, Randles, Cynthia, Wang, Rui, Guo, Xuehui, Clarisse, Lieven, Van Damme, Martin, Coheur, Pierre, Clerbaux, Cathy, Shephard, Mark W., Dammers, Enrico D. E., Cady-Pereira, Karen, Zondlo, Mark A., Beale, Christopher, Paulot, Fabien, Randles, Cynthia, Wang, Rui, Guo, Xuehui, Clarisse, Lieven, Van Damme, Martin, Coheur, Pierre, Clerbaux, Cathy, Shephard, Mark W., Dammers, Enrico D. E., Cady-Pereira, Karen, and Zondlo, Mark A.
- Abstract
Ammonia (NH 3 ) is a key precursor of haze particles and fine particulate matter (PM 2.5 ) and its spatiotemporal variabilities are poorly constrained. In this study, we present measurements of NH 3 over the Indian subcontinent region from the Infrared Atmospheric Sounder Interferometer (IASI) and Cross-track Infrared Sounder (CrIS) satellite instruments. This region exhibits a complex emission profile due to the number of varied sources, including crop burning, fossil fuel combustion, fertilizer application, livestock and industrial sources. Observations from the CrIS and IASI instruments are oversampled to a resolution of 0.02° × 0.02°. Five regions with distinct spatiotemporal NH 3 profiles are determined using k-means clustering. Maximum NH 3 columns are seen in July over the western India with column densities of 6.2 × 10 17 mol cm −2 and 7.2 × 10 17 mol cm −2 respectively for IASI and CrIS. The seasonality of measured NH 3 columns show annual maxima occurring in spring in Eastern India and Bangladesh and in mid-summer for the western Indo-Gangetic plain. Our observational constraints suggest that the impact of local farming practices on NH 3 emissions is not well captured in emission inventories such as Coupled Model Intercomparison Project Phase 6 (CMIP6), which exhibits peaks in the late spring and autumn. The spatial variability in the seasonal patterns of NH 3 is also not captured by the single emissions profile used in CMIP6 for India. The high-resolution maps obtained from these measurements can be used to improve NH 3 emission inventories in order to understand its sources for more accurate predictions of air quality in the Indian subcontinent. Our study points to the need for regionally specific emissions inventories for short-lived species such as NH3 that have heterogeneous emissions profiles due to specific agricultural practices and other emission source characteristics., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2022
34. Supplementary material to "Robust evidence for reversal in the aerosol effective climate forcing trend"
- Author
-
Quaas, Johannes, primary, Jia, Hailing, additional, Smith, Chris, additional, Albright, Anna Lea, additional, Aas, Wenche, additional, Bellouin, Nicolas, additional, Boucher, Olivier, additional, Doutriaux-Boucher, Marie, additional, Forster, Piers M., additional, Grosvenor, Daniel, additional, Jenkins, Stuart, additional, Klimont, Zig, additional, Loeb, Norman G., additional, Ma, Xiaoyan, additional, Naik, Vaishali, additional, Paulot, Fabien, additional, Stier, Philip, additional, Wild, Martin, additional, Myhre, Gunnar, additional, and Schulz, Michael, additional
- Published
- 2022
- Full Text
- View/download PDF
35. Robust evidence for reversal in the aerosol effective climate forcing trend
- Author
-
Quaas, Johannes, primary, Jia, Hailing, additional, Smith, Chris, additional, Albright, Anna Lea, additional, Aas, Wenche, additional, Bellouin, Nicolas, additional, Boucher, Olivier, additional, Doutriaux-Boucher, Marie, additional, Forster, Piers M., additional, Grosvenor, Daniel, additional, Jenkins, Stuart, additional, Klimont, Zig, additional, Loeb, Norman G., additional, Ma, Xiaoyan, additional, Naik, Vaishali, additional, Paulot, Fabien, additional, Stier, Philip, additional, Wild, Martin, additional, Myhre, Gunnar, additional, and Schulz, Michael, additional
- Published
- 2022
- Full Text
- View/download PDF
36. Unexpected Epoxide Formation in the Gas-Phase Photooxidation of Isoprene
- Author
-
Paulot, Fabien, Crounse, John D., Kjaergaard, Henrik G., Kürten, Andreas, Clair, Jason M. St., Seinfeld, John H., and Wennberg, Paul O.
- Published
- 2009
- Full Text
- View/download PDF
37. Improving Estimates of Sulfur, Nitrogen, and Ozone Total Deposition through Multi-Model and Measurement-Model Fusion Approaches
- Author
-
Fu, Joshua S., primary, Carmichael, Gregory R., additional, Dentener, Frank, additional, Aas, Wenche, additional, Andersson, Camilla, additional, Barrie, Leonard A., additional, Cole, Amanda, additional, Galy-Lacaux, Corinne, additional, Geddes, Jeffrey, additional, Itahashi, Syuichi, additional, Kanakidou, Maria, additional, Labrador, Lorenzo, additional, Paulot, Fabien, additional, Schwede, Donna, additional, Tan, Jiani, additional, and Vet, Robert, additional
- Published
- 2022
- Full Text
- View/download PDF
38. Moisture Fluctuations Modulate Abiotic and Biotic Limitations of H 2 Soil Uptake
- Author
-
Bertagni, Matteo B., primary, Paulot, Fabien, additional, and Porporato, Amilcare, additional
- Published
- 2021
- Full Text
- View/download PDF
39. Understanding Top‐of‐Atmosphere Flux Bias in the AeroCom Phase III Models: A Clear‐Sky Perspective
- Author
-
Su, Wenying, primary, Liang, Lusheng, additional, Myhre, Gunnar, additional, Thorsen, Tyler J., additional, Loeb, Norman G., additional, Schuster, Gregory L., additional, Ginoux, Paul, additional, Paulot, Fabien, additional, Neubauer, David, additional, Checa‐Garcia, Ramiro, additional, Matsui, Hitoshi, additional, Tsigaridis, Kostas, additional, Skeie, Ragnhild B., additional, Takemura, Toshihiko, additional, Bauer, Susanne E., additional, and Schulz, Michael, additional
- Published
- 2021
- Full Text
- View/download PDF
40. Calculation of conformationally weighted dipole moments useful in ion–molecule collision rate estimates
- Author
-
Garden, Anna L., Paulot, Fabien, Crounse, John D., Maxwell-Cameron, Isobel J., Wennberg, Paul O., and Kjaergaard, Henrik G.
- Published
- 2009
- Full Text
- View/download PDF
41. Reduction in Near‐Surface Wind Speeds With Increasing CO2 May Worsen Winter Air Quality in the Indo‐Gangetic Plain.
- Author
-
Paulot, Fabien, Naik, Vaishali, and W. Horowitz, Larry
- Subjects
- *
WIND speed , *AIR quality , *AIR pollution control , *AIR pollutants , *PARTICULATE matter , *AIR pollution - Abstract
We analyze the relationship between fine particulate matter (PM2.5) and meteorology in winter in the Indo‐Gangetic Plain (IGP). We find that the concentration of PM2.5 exhibits similar increase with decreasing surface wind speed in 15 out of 18 cities considered. Using this observed relationship, we estimate that the reduction of surface wind speed with increasing CO2 simulated by models participating in the Coupled Model Intercomparison Project Phase 6 will result in higher average wintertime PM2.5 concentrations (1% per degree K of global warming) and more frequent high‐pollution events. This observation‐based estimate is qualitatively consistent with the simulated response of black carbon to global warming inferred from the AerChemMIP ssp370SST and ssp370pdSST experiments. We hypothesize that a reduction in the frequency and intensity of western disturbances with increasing CO2 may contribute to the reduction in the surface wind in the IGP. Plain Language Summary: The Indo‐Gangetic Plain, home to over 800 million people, experiences among the most elevated concentrations of fine particulate matter in the world. Such high levels of air pollution are estimated to reduce average life expectancy by several years. Air quality is especially poor in wintertime, in part due to meteorological conditions such as slow wind speeds that favor the accumulation of air pollutants near the surface. CMIP6 models project that increasing CO2 will cause a reduction in surface wind speed in the Indo‐Gangetic Plain. We show that this reduction in wind speed will result in higher wintertime PM2.5 concentration (1%/K) and more frequent high‐PM2.5 days. This CO2 penalty highlights the need for stringent air pollution controls in this region. Key Points: In winter, slow wind speeds are often accompanied by high concentrations of PM2.5 in the Indo‐Gangetic PlainWind speeds are projected to decrease with increasing CO2 worsening PM2.5Slower wind speeds may be caused by less frequent and less intense western disturbances [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
42. US SOLAS Science Report
- Author
-
Stanley, Rachel H. R., Bell, Tom G., Gao, Yuan, Gaston, Cassandra J., Ho, David T., Kieber, David J., Mackey, Katherine R. M., Meskhidze, Nicholas, Miller, William L., Potter, Henry, Vlahos, Penny, Yager, Patricia L., Alexander, Becky, Beaupre, Steven R., Craig, Susanne E., Cutter, Gregory A., Emerson, Steven, Frossard, Amanda A., Gasso, Santiago, Haus, Brian K., Keene, William C., Landing, William M., Moore, Richard H., Ortiz-Suslow, David, Palter, Jaime B., Paulot, Fabien, Saltzman, Eric, Thornton, Daniel, Wozniak, Andrew S., Zamora, Lauren M., Benway, Heather M., Stanley, Rachel H. R., Bell, Tom G., Gao, Yuan, Gaston, Cassandra J., Ho, David T., Kieber, David J., Mackey, Katherine R. M., Meskhidze, Nicholas, Miller, William L., Potter, Henry, Vlahos, Penny, Yager, Patricia L., Alexander, Becky, Beaupre, Steven R., Craig, Susanne E., Cutter, Gregory A., Emerson, Steven, Frossard, Amanda A., Gasso, Santiago, Haus, Brian K., Keene, William C., Landing, William M., Moore, Richard H., Ortiz-Suslow, David, Palter, Jaime B., Paulot, Fabien, Saltzman, Eric, Thornton, Daniel, Wozniak, Andrew S., Zamora, Lauren M., and Benway, Heather M.
- Abstract
The Surface Ocean – Lower Atmosphere Study (SOLAS) (http://www.solas-int.org/) is an international research initiative focused on understanding the key biogeochemical-physical interactions and feedbacks between the ocean and atmosphere that are critical elements of climate and global biogeochemical cycles. Following the release of the SOLAS Decadal Science Plan (2015-2025) (Brévière et al., 2016), the Ocean-Atmosphere Interaction Committee (OAIC) was formed as a subcommittee of the Ocean Carbon and Biogeochemistry (OCB) Scientific Steering Committee to coordinate US SOLAS efforts and activities, facilitate interactions among atmospheric and ocean scientists, and strengthen US contributions to international SOLAS. In October 2019, with support from OCB, the OAIC convened an open community workshop, Ocean-Atmosphere Interactions: Scoping directions for new research with the goal of fostering new collaborations and identifying knowledge gaps and high-priority science questions to formulate a US SOLAS Science Plan. Based on presentations and discussions at the workshop, the OAIC and workshop participants have developed this US SOLAS Science Plan. The first part of the workshop and this Science Plan were purposefully designed around the five themes of the SOLAS Decadal Science Plan (2015-2025) (Brévière et al., 2016) to provide a common set of research priorities and ensure a more cohesive US contribution to international SOLAS.
- Published
- 2021
43. Climate-driven chemistry and aerosol feedbacks in CMIP6 Earth system models
- Author
-
Thornhill, Gillian, Collins, William, Olivié, Dirk, Skeie, Ragnhild B., Archibald, Alex, Bauer, Susanne, Checa-Garcia, Ramiro, Fiedler, Stephanie, Folberth, Gerd, Gjermundsen, Ada, Horowitz, Larry, Lamarque, Jean-Francois, Michou, Martine, Mulcahy, Jane, Nabat, Pierre, Naik, Vaishali, O'Connor, Fiona M., Paulot, Fabien, Schulz, Michael, Scott, Catherine E., Séférian, Roland, Smith, Chris, Takemura, Toshihiko, Tilmes, Simone, Tsigaridis, Kostas, Weber, James, Thornhill, Gillian, Collins, William, Olivié, Dirk, Skeie, Ragnhild B., Archibald, Alex, Bauer, Susanne, Checa-Garcia, Ramiro, Fiedler, Stephanie, Folberth, Gerd, Gjermundsen, Ada, Horowitz, Larry, Lamarque, Jean-Francois, Michou, Martine, Mulcahy, Jane, Nabat, Pierre, Naik, Vaishali, O'Connor, Fiona M., Paulot, Fabien, Schulz, Michael, Scott, Catherine E., Séférian, Roland, Smith, Chris, Takemura, Toshihiko, Tilmes, Simone, Tsigaridis, Kostas, and Weber, James
- Abstract
Feedbacks play a fundamental role in determining the magnitude of the response of the climate system to external forcing, such as from anthropogenic emissions. The latest generation of Earth system models includes aerosol and chemistry components that interact with each other and with the biosphere. These interactions introduce a complex web of feedbacks that is important to understand and quantify. This paper addresses multiple pathways for aerosol and chemical feedbacks in Earth system models. These focus on changes in natural emissions (dust, sea salt, dimethyl sulfide, biogenic volatile organic compounds (BVOCs) and lightning) and changes in reaction rates for methane and ozone chemistry. The feedback terms are then given by the sensitivity of a pathway to climate change multiplied by the radiative effect of the change. We find that the overall climate feedback through chemistry and aerosols is negative in the sixth Coupled Model Intercomparison Project (CMIP6) Earth system models due to increased negative forcing from aerosols in a climate with warmer surface temperatures following a quadrupling of CO2 concentrations. This is principally due to increased emissions of sea salt and BVOCs which are sensitive to climate change and cause strong negative radiative forcings. Increased chemical loss of ozone and methane also contributes to a negative feedback. However, overall methane lifetime is expected to increase in a warmer climate due to increased BVOCs. Increased emissions of methane from wetlands would also offset some of the negative feedbacks. The CMIP6 experimental design did not allow the methane lifetime or methane emission changes to affect climate, so we found a robust negative contribution from interactive aerosols and chemistry to climate sensitivity in CMIP6 Earth system models.
- Published
- 2021
- Full Text
- View/download PDF
44. US SOLAS Science Report
- Author
-
Naval Postgraduate School (U.S.), Oceanography, Stanley, Rachel H.R., Bell, Tom G., Gao, Yuan, Gaston, Cassandra J., Ho, David T., Kieber, David J., Mackey, Katherine R.M., Meskhidze, Nicholas, Miller, William L., Potter, Henry, Vlahos, Penny, Yager, Patricia L., Alexander, Becky, Beaupre, Steven R., Craig, Susanne E., Cutter, Gregory A., Emerson, Steven, Frossard, Amanda A., Gasso, Santiago, Haus, Brian K., Keene, William C., Landing, William M., Moore, Richard H., Ortiz-Suslow, David, Palter, Jaime B., Paulot, Fabien, Saltzman, Eric, Thornton, Daniel, Wozniak, Andrew S., Zamora, Lauren M., Benway, Heather M., Naval Postgraduate School (U.S.), Oceanography, Stanley, Rachel H.R., Bell, Tom G., Gao, Yuan, Gaston, Cassandra J., Ho, David T., Kieber, David J., Mackey, Katherine R.M., Meskhidze, Nicholas, Miller, William L., Potter, Henry, Vlahos, Penny, Yager, Patricia L., Alexander, Becky, Beaupre, Steven R., Craig, Susanne E., Cutter, Gregory A., Emerson, Steven, Frossard, Amanda A., Gasso, Santiago, Haus, Brian K., Keene, William C., Landing, William M., Moore, Richard H., Ortiz-Suslow, David, Palter, Jaime B., Paulot, Fabien, Saltzman, Eric, Thornton, Daniel, Wozniak, Andrew S., Zamora, Lauren M., and Benway, Heather M.
- Abstract
The Surface Ocean – Lower Atmosphere Study (SOLAS) (http://www.solas-int.org/) is an international research initiative focused on understanding the key biogeochemical-physical interactions and feedbacks between the ocean and atmosphere that are critical elements of climate and global biogeochemical cycles. Following the release of the SOLAS Decadal Science Plan (2015-2025) (Brévière et al., 2016), the Ocean-Atmosphere Interaction Committee (OAIC) was formed as a subcommittee of the Ocean Carbon and Biogeochemistry (OCB) Scientific Steering Committee to coordinate US SOLAS efforts and activities, facilitate interactions among atmospheric and ocean scientists, and strengthen US contributions to international SOLAS. In October 2019, with support from OCB, the OAIC convened an open community workshop, Ocean-Atmosphere Interactions: Scoping directions for new research with the goal of fostering new collaborations and identifying knowledge gaps and high-priority science questions to formulate a US SOLAS Science Plan. Based on presentations and discussions at the workshop, the OAIC and workshop participants have developed this US SOLAS Science Plan. The first part of the workshop and this Science Plan were purposefully designed around the five themes of the SOLAS Decadal Science Plan (2015-2025) (Brévière et al., 2016) to provide a common set of research priorities and ensure a more cohesive US contribution to international SOLAS.
- Published
- 2021
45. Monthly Patterns of Ammonia Over the Contiguous United States at 2-km Resolution
- Author
-
Wang, Rui, Guo, Xuehui, Pan, Da, Kelly, James J.T., Bash, Jesse, Sun, Kang, Paulot, Fabien, Clarisse, Lieven, Van Damme, Martin, Whitburn, Simon, Coheur, Pierre, Clerbaux, Cathy, Zondlo, Mark A., Wang, Rui, Guo, Xuehui, Pan, Da, Kelly, James J.T., Bash, Jesse, Sun, Kang, Paulot, Fabien, Clarisse, Lieven, Van Damme, Martin, Whitburn, Simon, Coheur, Pierre, Clerbaux, Cathy, and Zondlo, Mark A.
- Abstract
Monthly, high-resolution (∼2 km) ammonia (NH3) column maps from the Infrared Atmospheric Sounding Interferometer (IASI) were developed across the contiguous United States and adjacent areas. Ammonia hotspots (95th percentile of the column distribution) were highly localized with a characteristic length scale of 12 km and median area of 152 km2. Five seasonality clusters were identified with k-means++ clustering. The Midwest and eastern United States had a broad, spring maximum of NH3 (67% of hotspots in this cluster). The western United States, in contrast, showed a narrower midsummer peak (32% of hotspots). IASI spatiotemporal clustering was consistent with those from the Ammonia Monitoring Network. CMAQ and GFDL-AM3 modeled NH3 columns have some success replicating the seasonal patterns but did not capture the regional differences. The high spatial-resolution monthly NH3 maps serve as a constraint for model simulations and as a guide for the placement of future, ground-based network sites., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2021
46. Corrigendum to “Air quality impacts from the electrification of light-duty passenger vehicles in the United States” [Atmos. Environ. 208 (2019) 95–102]
- Author
-
Schnell, Jordan L., Naik, Vaishali, Horowitz, Larry W., Paulot, Fabien, Ginoux, Paul, Zhao, Ming, and Horton, Daniel E.
- Published
- 2020
- Full Text
- View/download PDF
47. Monthly Patterns of Ammonia Over the Contiguous United States at 2‐km Resolution
- Author
-
Wang, Rui, primary, Guo, Xuehui, additional, Pan, Da, additional, Kelly, James T., additional, Bash, Jesse O., additional, Sun, Kang, additional, Paulot, Fabien, additional, Clarisse, Lieven, additional, Van Damme, Martin, additional, Whitburn, Simon, additional, Coheur, Pierre‐François, additional, Clerbaux, Cathy, additional, and Zondlo, Mark A., additional
- Published
- 2021
- Full Text
- View/download PDF
48. Assessing the Influence of COVID‐19 on the Shortwave Radiative Fluxes Over the East Asian Marginal Seas
- Author
-
Ming, Yi, primary, Loeb, Norman G., additional, Lin, Pu, additional, Shen, Zhaoyi, additional, Naik, Vaishali, additional, Singer, Clare E., additional, Ward, Ryan X., additional, Paulot, Fabien, additional, Zhang, Zhibo, additional, Bellouin, Nicolas, additional, Horowitz, Larry W., additional, Ginoux, Paul A., additional, and Ramaswamy, V., additional
- Published
- 2021
- Full Text
- View/download PDF
49. Climate-driven chemistry and aerosol feedbacks in CMIP6 Earth system models
- Author
-
Thornhill, Gillian, primary, Collins, William, additional, Olivié, Dirk, additional, Skeie, Ragnhild B., additional, Archibald, Alex, additional, Bauer, Susanne, additional, Checa-Garcia, Ramiro, additional, Fiedler, Stephanie, additional, Folberth, Gerd, additional, Gjermundsen, Ada, additional, Horowitz, Larry, additional, Lamarque, Jean-Francois, additional, Michou, Martine, additional, Mulcahy, Jane, additional, Nabat, Pierre, additional, Naik, Vaishali, additional, O'Connor, Fiona M., additional, Paulot, Fabien, additional, Schulz, Michael, additional, Scott, Catherine E., additional, Séférian, Roland, additional, Smith, Chris, additional, Takemura, Toshihiko, additional, Tilmes, Simone, additional, Tsigaridis, Kostas, additional, and Weber, James, additional
- Published
- 2021
- Full Text
- View/download PDF
50. Stomatal conductance influences interannual variability and long-term changes in regional cumulative plant uptake of ozone
- Author
-
Clifton, Olivia E, primary, Lombardozzi, Danica L, additional, Fiore, Arlene M, additional, Paulot, Fabien, additional, and Horowitz, Larry W, additional
- Published
- 2020
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.