Numerical study of direct variational algorithm for assimilation of atmospheric chemistry data into transport and transformation model

2016 ◽  
Author(s):  
Alexey Penenko ◽  
Pavel Antokhin
Keyword(s):  
Atmospheric Chemistry ◽  
Numerical Study ◽  
Transformation Model ◽  
Transport And Transformation ◽  
Chemistry Data

Investigation of strongly enhanced methane Part I: Chemical feedbacks and rapid adjustments.

2020 ◽  
Author(s):  
Franziska Winterstein ◽  
Patrick Jöckel ◽  
Martin Dameris ◽  
Michael Ponater ◽  
Fabian Tanalski ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Radiative Forcing ◽  
Climate Model ◽  
Numerical Study ◽  
Stratospheric Ozone ◽  
Lower Boundary ◽  
Tropospheric Chemistry ◽  
Substantial Part ◽  
Mixing Ratios ◽  
The Impact

<p>Methane (CH<sub>4</sub>) is the second most important greenhouse gas, which atmospheric concentration is influenced by human activities and currently on a sharp rise. We present a study with numerical simulations using a Chemistry-Climate-Model (CCM), which are performed to assess possible consequences of strongly enhanced CH<sub>4</sub> concentrations in the Earth's atmosphere for the climate.</p><p>Our analysis includes experiments with 2xCH<sub>4</sub> and 5xCH<sub>4</sub> present day (2010) lower boundary mixing ratios using the CCM EMAC. The simulations are conducted with prescribed oceanic conditions, mimicking present day tropospheric temperatures as its changes are largely suppressed. By doing so we are able to investigate the quasi-instantaneous chemical impact on the atmosphere. We find that the massive increase in CH<sub>4</sub> strongly influences the tropospheric chemistry by reducing the OH abundance and thereby extending the tropospheric CH<sub>4</sub> lifetime as well as the residence time of other chemical pollutants. The region above the tropopause is impacted by a substantial rise in stratospheric water vapor (SWV). The stratospheric ozone (O<sub>3</sub>) column increases overall, but SWV induced stratospheric cooling also leads to enhanced ozone depletion in the Antarctic lower stratosphere. Regional  patterns of ozone change are affected by modification of stratospheric dynamics, i.e. increased tropical up-welling and stronger meridional transport  towards the polar regions. We calculate the net radiative impact (RI) of the 2xCH<sub>4</sub> experiment to be 0.69 W m<sup>-2</sup> and for the 5xCH<sub>4</sub> experiment to be 1.79 W m<sup>-2</sup>. A substantial part of the RI is contributed by chemically induced O<sub>3</sub> and SWV changes, in line with previous radiative forcing estimates and is for the first time splitted and spatially asigned to its chemical contributors.</p><p>This numerical study using a CCM with prescibed oceanic conditions shows the rapid responses to significantly enhanced CH<sub>4</sub> mixing ratios, which is the first step towards investigating the impact of possible strong future CH<sub>4</sub> emissions on atmospheric chemistry and its feedback on climate.</p>

scholarly journals NUMERICAL ANALYSIS OF THE OBSERVABILITY OF THE CITY ROAD NETWORK EMISSION SOURCES USING THE SENSITIVITY OPERATOR OF THE ATMOSPHERIC CHEMISTRY TRANSPORT AND TRANSFORMATION MODEL

2021 ◽  
Vol 4 (1) ◽  
pp. 177-184
Author(s):  
Alexey V. Penenko ◽  
Alexander V. Gochakov
Keyword(s):  
Atmospheric Chemistry ◽  
Road Network ◽  
Identification Problem ◽  
Transformation Model ◽  
Emission Sources ◽  
Problem Solution ◽  
Accuracy Evaluation ◽  
Traffic Emission ◽  
The City ◽  
Sensitivity Operator

Within the scenario approach, the observability of traffic emission sources is estimated from indirect monitoring data. What is new is that an approach based on sensitivity operators is used to estimate observability, which allows us to obtain a family of quasilinear operator equations for the source identification problem. This allows both solving and analyzing its properties. For the city of Novosibirsk, realistic weather scenarios, a scenario for the distribution of traffic emission sources and the location of monitoring sites are considered. In numerical experiments, the road network is identified smoothed over space. Concentration fields are restored with greater accuracy. Evaluation of the information about the sources contained in the data based on the analysis of the sensitivity operator allows one to get an express estimate of the inverse problem solution.

scholarly journals Implication of extreme atmospheric methane concentrations for chemistry-climate connections

2019 ◽  
Author(s):  
Franziska Winterstein ◽  
Fabian Tanalski ◽  
Patrick Jöckel ◽  
Martin Dameris ◽  
Michael Ponater
Keyword(s):  
Atmospheric Chemistry ◽  
Radiative Forcing ◽  
Climate Model ◽  
Numerical Study ◽  
Stratospheric Ozone ◽  
Tropospheric Chemistry ◽  
Substantial Part ◽  
Atmospheric Concentration ◽  
Regional Patterns ◽  
The Impact

Abstract. Methane (CH4) is the second most important greenhouse gas, which atmospheric concentration is influenced by human activities. In this study, numerical simulations with a chemistry-climate model (CCM) are performed aiming to assess possible consequences of significantly enhanced CH4 concentrations in the Earth's atmosphere for the climate. We analyze experiments with 2xCH4 and 5xCH4 present day (2010) mixing ratio and its quasi-instantaneous chemical impact on the atmosphere. The massive increase in CH4 strongly influences the tropospheric chemistry by reducing the hydroxyl radical (OH) abundance and thereby extending the CH4 lifetime as well as the residence time of other chemical pollutants. The region above the tropopause is impacted by a substantial rise in stratospheric water vapor (SWV). The stratospheric ozone (O3) column increases overall, but SWV induced stratospheric cooling also leads to a enhanced ozone depletion in the Antarctic lower stratosphere. Regional patterns of ozone change are affected by modification of stratospheric dynamics, i.e. increased tropical up-welling and stronger meridional transport towards the polar regions. We calculate the net radiative impact (RI) of the 2xCH4 experiment to be 0.69 W/m2 and for the 5xCH4 experiment to be 1.79 W/m2. A substantial part of the RI is contributed by chemically induced O3 and SWV changes, in line with previous radiative forcing estimates. To our knowledge this is the first numerical study using a CCM with respect to two/fivefold CH4 concentrations and it is therefore an overdue analysis as it emphasizes the impact of possible strong future CH4 emissions on atmospheric chemistry and its feedback on climate.

An unknown maximum lag-correlation between rainfall and aerosols at 140-160 minutes

2021 ◽  
Author(s):  
Pinhas Alpert ◽  
Haim Shafir ◽  
Emily Elhacham
Keyword(s):  
Time Series ◽  
Time Scales ◽  
Atmospheric Chemistry ◽  
Numerical Study ◽  
Aerosol Concentration ◽  
Hygroscopic Growth ◽  
Plain Language ◽  
Geophysical Research ◽  
Near Surface ◽  
The Earth

<p>Keywords:</p><p>Scavenging process, Rainfall, Aerosols, Lag correlation, Rainfall-aerosol processes</p><p>Abstract</p><p>Rainfall and aerosols play major roles in the Earth climate system and substantially influence our life. Here, the focus is on the local near-surface aerosol/rainfall correlations with time-scales of minutes to days. We investigated 29 experiments including 14 specific rain events, with time resolutions of daily and 60, 30, 10 minutes at ten stations in Israel and California. The highest negative correlations were consistently at a positive lag of about 140-160 minutes where a positive lag means that the aerosol time-series follows that of the rain. The highest negative value is suggested to be the probable outcome of immediate scavenging along with the rise in aerosol concentration after rain depending on aerosol sources, hygroscopic growth and transport. The scavenging dominance is expressed by the mostly negative lag-correlation values in all experiments. In addition, the consistent lack of significant correlation found at negative lags suggest a weak aerosol effect on precipitation (Gryspeerdt et al., 2015).</p><p>Plain Language Summary: Rainfall and atmospheric particles (aerosols) play significant roles in the Earth atmosphere and largely influence our weather and climate. The relations between near-surface aerosol and rainfall on time scales of minutes to days are studied, employing correlations in 10 meteorological stations in Israel and California. The highest negative correlations were consistently at a positive lag of about 140-160 minutes. A positive lag means that the aerosol time-series follows that of the rain. The highest negative correlation value is suggested to be the outcome of scavenging along with the rise in aerosol concentration after rain depending on the sources of aerosols, hygroscopic growth and transport. <strong>Furthermore, our approach provides a more fundamental insight into the local, near-surface rain-aerosol interactions, in contrast to many aerosol-rainfall studies that are climatological and with the tele-connection approach (Alpert et al., 2008), which involves other processes over distances of a few km up to even large synoptic scales.</strong></p><p>            </p><p><strong>Relevant References:</strong></p><p>Alpert, P., Halfon, N., & Levin, Z. (2008). Does Air Pollution Really Suppress Precipitation in Israel? Journal of Applied Meteorology and Climatology. https://doi.org/10.1175/2007jamc1803.1</p><p>Barkan, J., & Alpert, P. (2020). Red Snow occurrence in Eastern Europe - A case study. Weather. https://doi.org/10.1002/wea.3644</p><p>Gryspeerdt, E., Stier, P., White, B. A., & Kipling, Z. (2015). Wet scavenging limits the detection of aerosol effects on precipitation. Atmospheric Chemistry and Physics, 15(13), 7557–7570.</p><p>Tsidulko, M., Krichak, S. O., Alpert, P., Kakaliagou, O., Kallos, G., & Papadopoulos, A. (2002). Numerical study of a very intensive eastern Mediterranean dust storm, 13-16 March 1998. Journal of Geophysical Research: Atmospheres. https://doi.org/10.1029/2001jd001168</p>

Modeling of Southeast Asia biomass burning pollutants to Taiwan during EMeRGe campaigns in Asia

2020 ◽  
Author(s):  
Chuan-yao Lin ◽  
Wan-chin Chen ◽  
Yang-fan sheng ◽  
Win-Mei Chen ◽  
Yi-Yun Chien
Keyword(s):  
East Asia ◽  
Long Range ◽  
Biomass Burning ◽  
Air Pollutants ◽  
Numerical Study ◽  
Lower Troposphere ◽  
Weather Conditions ◽  
Transport And Transformation ◽  
Complex Interactions ◽  
Vertical Profiling

<p>In springtime happens to be the biomass burning season in Indochina. Under favor weather conditions, the products of biomass burning pollutants could be transported easily to Taiwan and even East Asia. Actually, the complex interactions of these air pollutants and aerosols features in the boundary layer and aloft have resulted in complex characteristics of air pollutants and aerosols distributions in the lower troposphere. The project “Effect of Megacities on the transport and transformation of pollutants on the Regional and Global scales (EMeRGe)” aims to improve our knowledge and prediction of the transport and transformation patterns of European and Asian megacities pollutant outflows. During the EMeRGe campaign in Asia, the composition of the plumes of pollution entering and leaving Asia measured by the new High Altitude and LOng Range (HALO) aircraft research platform. The HALO aircraft performing optimized transects and vertical profiling in Asia during 12 March and 7 April in 2018. To identify the transportation of biomass burning products, a high resolution (9 km) numerical study by Weather Research Forecast coupled with chemistry model (WRF-Chem) was performed during the campaigns. The long-range transport of biomass burning organic aerosol to Taiwan measured by HALO could be more than 2 ug/m3 at the elevation of 2500 m on 20 March, 2018. Model performances and results will discuss in this meeting. Overall, this series of studies significantly fill the gap of our understanding on air pollutants transformation and transport to Taiwan and East Asia, and show the potential directions of future studies.</p>

Atmospheric transport and transformation

1984 ◽  
Vol 305 (1124) ◽  
pp. 259-279 ◽  
Keyword(s):  
Nitrogen Oxide ◽  
Atmospheric Chemistry ◽  
Sulphur Dioxide ◽  
Western Europe ◽  
Meteorological Factors ◽  
Atmospheric Transport ◽  
Transport And Transformation ◽  
Deposition Of Pollutants ◽  
Episodic Nature

The meteorological factors determining the dispersion and deposition of pollutants are described. The results and limitations of attempts to model the deposition of anthropogenic sulphur over western Europe are given and compared with the measured deposition fields. The difficulty of monitoring the deposition on this scale is also emphasized as is the episodic nature of much of the deposition. Finally the atmospheric chemistry involved in the oxidation of sulphur dioxide and nitrogen oxide is described and evidence presented to illustrate the complexity of the factors determining the acidity of rain.

Sign in / Sign up

Export Citation Format

Share Document