Ammonia measurements from space with the Cross-track Infrared Sounder: characteristics and applications

Abstract. Despite its clear importance, the monitoring of atmospheric ammonia, including its sources, sinks, and links to the greater nitrogen cycle, remains limited. Satellite data are helping to fill the gap in monitoring from sporadic conventional ground- and aircraft-based observations to better inform policymakers and assess the impact of any ammonia-related policies. Presented is a description and survey that demonstrate the capabilities of the Cross-track Infrared Sounder (CrIS) ammonia product for monitoring, air quality forecast model evaluation, dry deposition estimates, and emission estimates from an agricultural hotspot. For model evaluation, while there is a general agreement in the spatial allocation of known major agricultural ammonia hotspots across North America, the satellite observations show some high-latitude regions during peak forest fire activity often have ammonia concentrations approaching those in agricultural hotspots. The CrIS annual ammonia dry depositions in Canada (excluding the territories) and the US have average and annual variability values of ∼0.8±0.08 and ∼1.23±0.09 Tg N yr−1, respectively. These satellite-derived dry depositions of reactive nitrogen from NH3 with NO2 show an annual ratio of NH3 compared to their sum (NH3+NO2) of ∼82 % and ∼55 % in Canada and the US, respectively. Furthermore, we show the use of CrIS satellite observations to estimate annual and seasonal emissions near Lethbridge, Alberta, Canada, a region dominated by high-emission concentrated animal feeding operations (CAFOs); the satellite annual emission estimate of 37.1±6.3 kt yr−1 is at least double the value reported in current bottom-up emission inventories for this region.

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Ammonia measurements from space with the Cross-track Infrared Sounder (CrIS): characteristics and applications

10.5194/acp-2019-705 ◽

2019 ◽

Cited By ~ 1

Author(s):

Mark Shephard ◽

Enrico Dammers ◽

Karen E. Cady-Pereira ◽

Shailesh K. Kharol ◽

Jesse Thompson ◽

...

Keyword(s):

Dry Deposition ◽

Model Evaluation ◽

Forecast Model ◽

Concentrated Animal Feeding Operations ◽

Animal Feeding Operations ◽

Air Quality Forecast ◽

Emission Estimate ◽

High Emission ◽

Cross Track ◽

The Impact

Abstract. Despite its clear importance, the monitoring of atmospheric ammonia, including its sources, sinks and links to the greater nitrogen cycle, remains limited. Satellite data are helping to fill the gap in monitoring from sporadic conventional ground and aircraft-based observations, to better inform policymakers, and assess the impact of any ammonia-related policies. Presented is a description and survey that demonstrate the capabilities of the CrIS ammonia product for monitoring, air quality forecast model evaluation, dry deposition estimates, and emissions estimates from an agricultural hotspot. For model evaluation, while there is a general agreement in the spatial allocation of known major agricultural ammonia hotspots across North America some high-latitude regions during peak forest fire activity often have ammonia concentrations approaching those in agricultural hotspots. The CrIS annual ammonia dry deposition in Canada (excluding Territories) and the U.S. have average and annual variability values of ~0.8 ± 0.08 Tg N year−1 and ~1.23 ± 0.09 Tg N year−1, respectively. These satellite derived dry depositions of reactive nitrogen from NH3 with NO2 show an annual ratio of NH3 compared to their sum (NH3 + NO2) of ~82 % and ~55 % in Canada and U.S., respectively. Furthermore, we show the use of CrIS satellite observations to estimated annual and seasonal emissions near Lethbridge, AB, Canada a region dominated by high emission feedlots also referred to as Concentrated Animal Feeding Operations (CAFOs); the satellite annual emission estimate of 37.1 ± 6.3 kt/yr is at least double the value reported in current bottom-up emission inventories for this region.

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Ammonia measurements from space with the Cross-track Infrared Sounder (CrIS): characteristics and applications

10.5194/egusphere-egu2020-11346 ◽

2020 ◽

Author(s):

Mark Shephard ◽

Chris McLinden ◽

Enrico Dammers ◽

Shailesh Kharol ◽

Karen Cady-Pereira ◽

...

Keyword(s):

Air Quality ◽

North America ◽

Dry Deposition ◽

Forecast Model ◽

Satellite Observations ◽

Spatiotemporal Variability ◽

Air Quality Model ◽

Quality Model ◽

Air Quality Forecast ◽

The Impact

Satellite data are helping to fill monitoring gaps in order to better inform decision makers and assess the impact of ammonia-related policies.&#160; Presented is an overview demonstrating the current capabilities of the ammonia (NH3) data product derived from the CrIS satellite instrument for monitoring, air quality forecast model evaluation, dry deposition estimates, and emissions estimates.&#160; This includes examples of daily, seasonal, and annual observations of CrIS ammonia that demonstrate the spatiotemporal variability of ammonia globally. These results further demonstrate the ability of CrIS to observe regional changes in ammonia concentrations, such as spring maximum values over agricultural regions from the fertilizing of crops.&#160; Also shown is the importance contribution of wildfires, especially in regions where there is little or no agriculture sources, such as the northern latitudes in North America during summer.&#160; Initial comparisons of CrIS NH3 satellite observations with air quality model simulations show that while there is general agreement on the spatial distribution of the anthropogenic hotspots, some areas are markedly different.&#160; Some key findings are that dry deposition estimates of NH3 and NO2 from CrIS and the Ozone Monitoring Instrament (OMI), respectively, indicate that the NH3 dominates over most regions across North America. Their 2013 annual ratio shows NH3 accounting for ~82% and ~55 % of the combined reactive nitrogen dry deposition from these two species over Canada and the U.S.&#160; Furthermore, we show the use of CrIS satellite observations to estimate annual and seasonal emissions over Concentrated Animal Feeding Operations (CAFOs).&#160; These results are used to evaluate the seasonal and temporal emissions profiles used in bottom-up inventories over an agriculture hotspot, which are often underreported

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IMPACT OF THE CROSS-TRACK ERROR DISTRIBUTION LAW ON SAFE NAVIGATION IN NARROW WATERS

Shipping & Navigation ◽

10.31653/2306-5761.30.2020.58-66 ◽

2020 ◽

Vol 30 (1) ◽

pp. 58-66

Author(s):

I.I. Vorokhobin ◽

◽

Keyword(s):

Normal Distribution ◽

Error Distribution ◽

Distribution Law ◽

Track Error ◽

Safe Navigation ◽

The Cross ◽

Normal Law ◽

Vessel Motion ◽

Cross Track ◽

The Impact

The paper indicates that navigation in narrow waters requires navigators to use means of passage safety assessment prior to choosing a route. It is pointed out that a relevant factor when assessing the safe passage probability is the cross-track error distribution law, whose impact is the subject of the research. The article analyses recent developments and publications that have begun investigating this subject, and highlights previously unsolved parts of the general problem. The results revealed two equivalent approaches, as well as a navigational safety parameter, which are used to determine the probability of safe navigation in narrow waters on the chosen route. The need to develop advanced predictive vessel motion models is noted, while many researchers study the design of an information system for vessel motion simulation with complex dynamic models and an intelligence system for vessel motion prediction that imitates the learning process of an autonomous control unit created with the use of the artificial neural network. Methods for identification of vessel manoeuvring models are shown. Based on the analysis of vessel hydrodynamics, a nonlinear model frame of vessel manoeuvring is established. The available publications suggest using compound laws of the first and second types for describing random errors in navigation measurements as an alternative to the normal distribution law. The article examines the dependence of the safe narrow waters passage probability on the cross-track error distribution law. The normal law and compound laws of the first and second types are considered as the cross-track error distribution laws. A formula for estimating the safe passage probability in the manoeuvring area is given, and expressions for the distribution function of the normal law and compound laws of both types are obtained. To assess the impact of the cross-track error distribution law for the same route, the safe passage probability for the normal distribution law, as well as compound laws of the first and second types, was calculated. For the same route, the probability of safe passage was calculated with the use of onedimensional and two-dimensional density models. It is shown that the average relative difference between the estimated safe passage probability for both models is 0.3%, which confirms the validity of using a one-dimensional cross-track error distribution density.

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EXPORT OF SERVICES: IS DATA LOCALIZATION A BARRIER?

International Trade and Trade Policy ◽

10.21686/2410-7395-2020-2-22-32 ◽

2020 ◽

pp. 22-32

Author(s):

A. A. Koval ◽

A. D. Levashenko

Keyword(s):

Personal Data ◽

Vital Role ◽

Cross Border ◽

Digital Services ◽

Foreign Countries ◽

Data Flows ◽

The Us ◽

The Cross ◽

The Impact ◽

The Eu

The export of services is not related to the physical movement of goods across the border but is directly dependent on the cross-border movement of data. Cross-border data flows play a vital role in the cross-border provision of digital services. The international community pays particular attention to issues regarding the application of data localization policies. Indeed, this requirement significantly affects global trade in services. The data localization policy provides, according to the WTO, limiting the ability of companies to transfer data about internal users to foreign countries. Developing countries (Russia, China, etc.) involve the application of the localization requirement, i.e., first records in the country, personal data of citizens, while the EU and the US consider the total need of data localization as a barrier to international trade. The article assesses the impact of data regulation requirements on the export and import of digital services.

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Impact of Infrared, Microwave, and Radio Occultation Satellite Observations on Operational Numerical Weather Prediction

Monthly Weather Review ◽

10.1175/mwr-d-14-00101.1 ◽

2014 ◽

Vol 142 (11) ◽

pp. 4164-4186 ◽

Cited By ~ 14

Author(s):

L. Cucurull ◽

R. A. Anthes

Keyword(s):

Radio Occultation ◽

Positive Impact ◽

Weather Prediction ◽

Lower Troposphere ◽

Correlation Coefficients ◽

Forecast Model ◽

Satellite Observation ◽

Satellite Observations ◽

Satellite Systems ◽

The Impact

Abstract A comparison of the impact of infrared (IR), microwave (MW), and radio occultation (RO) observations on NCEP’s operational global forecast model over the month of March 2013 is presented. Analyses and forecasts with only IR, MW, and RO observations are compared with analyses and forecasts with no satellite data and with each other. Overall, the patterns of the impact of the different satellite systems are similar, with the MW observations producing the largest impact on the analyses and RO producing the smallest. Without RO observations, satellite radiances are over– or under–bias corrected and RO acts as an anchor observation, reducing the forecast biases globally. Positive correlation coefficients of temperature impacts are generally found between the different satellite observation analyses, indicating that the three satellite systems are affecting the global temperatures in a similar way. However, the correlation in the lower troposphere among all three systems is surprisingly small. Correlations for the moisture field tend to be small in the lower troposphere between the different satellite analyses. The impact of the satellite observations on the 500-hPa geopotential height forecasts is much different in the Northern and Southern Hemispheres. In the Northern Hemisphere, all the satellite observations together make a small positive impact compared to the base (no satellite) forecasts. The IR and MW, but not the RO, make a small positive impact when assimilated alone. The situation is considerably different in the Southern Hemisphere, where all the satellite observations together make a much larger positive impact, and all three observation types (IR, MW, and RO) make similar and significant impacts.

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Cross-track Infrared Sounder (CrIS) satellite observations of tropospheric ammonia

Atmospheric Measurement Techniques ◽

10.5194/amt-8-1323-2015 ◽

2015 ◽

Vol 8 (3) ◽

pp. 1323-1336 ◽

Cited By ~ 59

Author(s):

M. W. Shephard ◽

K. E. Cady-Pereira

Keyword(s):

Boundary Layer ◽

Central Valley ◽

Satellite Observations ◽

Retrieval Algorithm ◽

Mountainous Regions ◽

Uncertainty Estimates ◽

Cross Track ◽

The Impact ◽

Retrieval Bias

Abstract. Observations of atmospheric ammonia are important in understanding and modelling the impact of ammonia on both human health and the natural environment. We present a detailed description of a robust retrieval algorithm that demonstrates the capabilities of utilizing Cross-track Infrared Sounder (CrIS) satellite observations to globally retrieval ammonia concentrations. Initial ammonia retrieval results using both simulated and real observations show that (i) CrIS is sensitive to ammonia in the boundary layer with peak vertical sensitivity typically around ~ 850–750 hPa (~ 1.5 to 2.5 km), which can dip down close to the surface (~ 900 hPa) under ideal conditions, (ii) it has a minimum detection limit of ~ 1 ppbv (peak profile value typically at the surface), and (iii) the information content can vary significantly with maximum values of ~ 1 degree-of-freedom for signal. Comparisons of the retrieval with simulated "true" profiles show a small positive retrieval bias of 6% with a standard deviation of ~ ± 20% (ranging from ± 12 to ± 30% over the vertical profile). Note that these uncertainty estimates are considered as lower bound values as no potential systematic errors are included in the simulations. The CrIS NH3 retrieval applied over the Central Valley in CA, USA, demonstrates that CrIS correlates well with the spatial variability of the boundary layer ammonia concentrations seen by the nearby Quantum Cascade-Laser (QCL) in situ surface and the Tropospheric Emission Spectrometer (TES) satellite observations as part of the DISCOVER-AQ campaign. The CrIS and TES ammonia observations show quantitatively similar retrieved boundary layer values that are often within the uncertainty of the two observations. Also demonstrated is CrIS's ability to capture the expected spatial distribution in the ammonia concentrations, from elevated values in the Central Valley from anthropogenic agriculture emissions, to much lower values in the unpolluted or clean surrounding mountainous regions. These initial results demonstrate the capabilities of the CrIS satellite to measure ammonia.

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The Impact of a Change in Regulation on Environmental Disclosure: SAB92 and the US Chemical Industry

Issues in Social and Environmental Accounting ◽

10.22164/isea.v2i1.25 ◽

2008 ◽

Vol 2 (1) ◽

pp. 61 ◽

Cited By ~ 6

Author(s):

Kathryn Bewley ◽

Vanessa Magness

Keyword(s):

Chemical Industry ◽

Economic Cost ◽

Pollutant Emissions ◽

Annual Reports ◽

Environmental Disclosure ◽

Environmental Liabilities ◽

Public Companies ◽

The Us ◽

High Emission ◽

The Impact

This study investigates environmental disclosure in the annual reports of US public companies in the chemical industry during a time when there was a substantial change in reporting regulation. This change concerned contingent environmental liabilities. We draw on signal theory and the economic cost perspective to generate predictions about environmental disclosure strategies. We find evidence that managers use disclosure to distinguish their companies from other companies: first by disclosing environmental liabilities that many other companies did not reveal; and later by disclosing other future-oriented financial information. We assumed initially, that this behaviour was indicative of signaling strategy. We find, however, that the companies which we initially thought were signaling have higher levels of pollutant emissions (per dollar of assets) than non- signaling companies. This evidence does not support our earlier assumption. We argue that public concern about this industry, and the fact that emissions levels are open to public scrutiny, lowers the disclosure-cost threshold for high emission companies, leading managers to disclose information they previously withheld.

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Cross-track Infrared Sounder (CrIS) satellite observations of tropospheric ammonia

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-7-11379-2014 ◽

2014 ◽

Vol 7 (11) ◽

pp. 11379-11413 ◽

Cited By ~ 4

Author(s):

M. W. Shephard ◽

K. E. Cady-Pereira

Keyword(s):

Boundary Layer ◽

Degrees Of Freedom ◽

Central Valley ◽

Satellite Observations ◽

Retrieval Algorithm ◽

Uncertainty Estimates ◽

Cross Track ◽

The Impact ◽

Retrieval Bias

Abstract. Observations of atmospheric ammonia are important in understanding and modeling the impact of ammonia on both human health and the natural environment. Presented is a detailed description of a robust retrieval algorithm that demonstrates the capabilities of utilizing Cross-track Infrared Sounder (CrIS) satellite observations to globally retrieval ammonia concentrations. Initial ammonia retrieval results using both simulated and real observations show that CrIS is: (i) sensitive to ammonia in the boundary layer, with peak vertical sensitivity typically around 800 hPa (~2 km), (ii) has a minimum detection limit of ~1 ppbv (peak profile value), and (iii) the information content can vary significantly with peak values of ~1 degrees-of-freedom for signal. Comparisons of the retrieval with simulated "true" profiles show there is small positive retrieval bias of 6%, with the variability being from 4% (25th quartile) to +26% (75th quartile). Note these uncertainty estimates are considered as lower bound values as no potential systematic errors are included in the simulations. The CrIS NH3 retrieval applied over the Central Valley in CA, USA demonstrates that CrIS can capture the general spatial variability of the boundary layer ammonia concentrations seen by the nearby Quantum Cascade-Laser (QCL) in-situ surface and the Tropospheric Emission Spectrometer (TES) satellite observations as part of the DISCOVER-AQ campaign. The CrIS and TES ammonia observations show quantitatively similar retrieved boundary layer values that are often within the uncertainty of the two observations. These initial results demonstrate the capabilities of the CrIS satellite to measure ammonia.

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Assessing the Impact of Corona-Virus-19 on Nitrogen Dioxide Levels over Southern Ontario, Canada

Remote Sensing ◽

10.3390/rs12244112 ◽

2020 ◽

Vol 12 (24) ◽

pp. 4112

Author(s):

Debora Griffin ◽

Chris Anthony McLinden ◽

Jacinthe Racine ◽

Michael David Moran ◽

Vitali Fioletov ◽

...

Keyword(s):

Air Quality ◽

Nitrogen Dioxide ◽

Forecast Model ◽

Activity Data ◽

Southern Ontario ◽

Greater Toronto Area ◽

Air Quality Forecast ◽

Scale Modelling ◽

Emission Activity ◽

The Impact

A lockdown was implemented in Canada mid-March 2020 to limit the spread of COVID-19. In the wake of this lockdown, declines in nitrogen dioxide (NO2) were observed from the TROPOspheric Monitoring Instrument (TROPOMI). A method is presented to quantify how much of this decrease is due to the lockdown itself as opposed to variability in meteorology and satellite sampling. The operational air quality forecast model, GEM-MACH (Global Environmental Multi-scale - Modelling Air quality and CHemistry), was used together with TROPOMI to determine expected NO2 columns that represents what TROPOMI would have observed for a non-COVID scenario. Applying this methodology to southern Ontario, decreases in NO2 emissions due to the lockdown were seen, with an average 40% (roughly 10 kt[NO2]/yr) in Toronto and Mississauga and even larger declines in the city center. Natural and satellite sampling variability accounted for as much as 20–30%, which demonstrates the importance of taking meteorology into account. A model run with reduced emissions (from 65 kt[NO2]/yr to 40 kt[NO2]/yr in the Greater Toronto Area) based on emission activity data during the lockdown period was found to be consistent with TROPOMI NO2 columns.

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VIIRS Captures Aurora Motions

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-12-00221.1 ◽

2013 ◽

Vol 94 (10) ◽

pp. 1491-1493 ◽

Cited By ~ 4

Author(s):

Curtis J. Seaman ◽

Steven D. Miller

Keyword(s):

Infrared Imaging ◽

Satellite Observations ◽

Physical Basis ◽

Relative Speed ◽

Apparent Position ◽

The Cross ◽

Cross Track

It has been found that the day/night band of the Visible Infrared Imaging Radiometer Suite is capable of observing rapid motions of the aurora. The images that led to this discovery are shown. Shifts in the apparent position of the aurora boundary between consecutive scans of the instrument, which occur ~1.79 s apart, allow the cross-track relative speed of the aurora to be calculated. The physical basis for these observations and the method for determining the speed of auroral motions are discussed. These new satellite observations compare favorably with ground-based measurements presented in previous studies.

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