scholarly journals Validation of SCIAMACHY HDO/H<sub>2</sub>O measurements using the TCCON and NDACC-MUSICA networks

2015 ◽  
Vol 8 (4) ◽  
pp. 1799-1818 ◽  
Author(s):  
R. A. Scheepmaker ◽  
C. Frankenberg ◽  
N. M. Deutscher ◽  
M. Schneider ◽  
S. Barthlott ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Hydrological Cycle ◽  
Source Region ◽  
Total Carbon ◽  
Atmospheric Composition ◽  
The Tibetan Plateau ◽  
Wet Season ◽  
Data Set ◽  
The Mean ◽  
The Impact

Abstract. Measurements of the atmospheric HDO/H2O ratio help us to better understand the hydrological cycle and improve models to correctly simulate tropospheric humidity and therefore climate change. We present an updated version of the column-averaged HDO/H2O ratio data set from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). The data set is extended with 2 additional years, now covering 2003–2007, and is validated against co-located ground-based total column δD measurements from Fourier transform spectrometers (FTS) of the Total Carbon Column Observing Network (TCCON) and the Network for the Detection of Atmospheric Composition Change (NDACC, produced within the framework of the MUSICA project). Even though the time overlap among the available data is not yet ideal, we determined a mean negative bias in SCIAMACHY δD of −35 ± 30‰ compared to TCCON and −69 ± 15‰ compared to MUSICA (the uncertainty indicating the station-to-station standard deviation). The bias shows a latitudinal dependency, being largest (∼ −60 to −80‰) at the highest latitudes and smallest (∼ −20 to −30‰) at the lowest latitudes. We have tested the impact of an offset correction to the SCIAMACHY HDO and H2O columns. This correction leads to a humidity- and latitude-dependent shift in δD and an improvement of the bias by 27‰, although it does not lead to an improved correlation with the FTS measurements nor to a strong reduction of the latitudinal dependency of the bias. The correction might be an improvement for dry, high-altitude areas, such as the Tibetan Plateau and the Andes region. For these areas, however, validation is currently impossible due to a lack of ground stations. The mean standard deviation of single-sounding SCIAMACHY–FTS differences is ∼ 115‰, which is reduced by a factor ∼ 2 when we consider monthly means. When we relax the strict matching of individual measurements and focus on the mean seasonalities using all available FTS data, we find that the correlation coefficients between SCIAMACHY and the FTS networks improve from 0.2 to 0.7–0.8. Certain ground stations show a clear asymmetry in δD during the transition from the dry to the wet season and back, which is also detected by SCIAMACHY. This asymmetry points to a transition in the source region temperature or location of the water vapour and shows the added information that HDO/H2O measurements provide when used in combination with variations in humidity.

scholarly journals Validation of SCIAMACHY HDO/H<sub>2</sub>O measurements using the TCCON and NDACC-MUSICA networks

2014 ◽  
Vol 7 (11) ◽  
pp. 11799-11851 ◽  
Author(s):  
R. A. Scheepmaker ◽  
C. Frankenberg ◽  
N. M. Deutscher ◽  
M. Schneider ◽  
S. Barthlott ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Hydrological Cycle ◽  
Source Region ◽  
Correlation Coefficients ◽  
Total Carbon ◽  
Atmospheric Composition ◽  
The Tibetan Plateau ◽  
Wet Season ◽  
The Mean ◽  
The Impact

Abstract. Measurements of the atmospheric HDO/H2O ratio help us to better understand the hydrological cycle and improve models to correctly simulate tropospheric humidity and therefore climate change. We present an updated version of the column-averaged HDO/H2O ratio dataset from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). The dataset is extended with two additional years, now covering 2003–2007, and is validated against co-located ground-based total column δD measurements from Fourier-Transform Spectrometers (FTS) of the Total Carbon Column Observing Network (TCCON) and the Network for the Detection of Atmospheric Composition Change (NDACC, produced within the framework of the MUSICA project). Even though the time overlap between the available data is not yet ideal, we determined a mean negative bias in SCIAMACHY δD of −35±30‰ compared to TCCON and −69±15‰ compared to MUSICA (the uncertainty indicating the station-to-station standard deviation). The bias shows a latitudinal dependency, being largest (∼ −60 to −80‰) at the highest latitudes and smallest (∼ −20 to −30‰) at the lowest latitudes. We have tested the impact of an offset correction to the SCIAMACHY HDO and H2O columns. This correction leads to a humidity and latitude dependent shift in δD and an improvement of the bias by 27‰, although it does not lead to an improved correlation with the FTS measurements nor to a strong reduction of the latitudinal dependency of the bias. The correction might be an improvement for dry, high-altitude areas, such as the Tibetan Plateau and the Andes region. For these areas, however, validation is currently impossible due to a lack of ground stations. The mean standard deviation of single-sounding SCIAMACHY–FTS differences is ∼ 115‰, which is reduced by a factor ∼ 2 when we consider monthly means. When we relax the strict matching of individual measurements and focus on the mean seasonalities using all available FTS data, we find that the correlation coefficients between SCIAMACHY and the FTS networks improve from 0.2 to 0.7–0.8. Certain ground stations show a clear asymmetry in δD during the transition from the dry to the wet season and back, which is also detected by SCIAMACHY. This asymmetry points to a transition in the source region temperature or location of the water vapor, and shows the added information that HDO/H2O measurements provide, if used in combination with variations in humidity.

scholarly journals Consistent evaluation of ACOS-GOSAT, BESD-SCIAMACHY, CarbonTracker, and MACC through comparisons to TCCON

2016 ◽  
Vol 9 (2) ◽  
pp. 683-709 ◽  
Author(s):  
Susan Kulawik ◽  
Debra Wunch ◽  
Christopher O'Dell ◽  
Christian Frankenberg ◽  
Maximilian Reuter ◽  
...  
Keyword(s):  
Mole Fraction ◽  
Seasonal Cycle ◽  
Atmospheric Co2 ◽  
Total Carbon ◽  
Atmospheric Composition ◽  
Cycle Phase ◽  
Data Set ◽  
Single Observation ◽  
Cycle Amplitude ◽  
The Impact

Abstract. Consistent validation of satellite CO2 estimates is a prerequisite for using multiple satellite CO2 measurements for joint flux inversion, and for establishing an accurate long-term atmospheric CO2 data record. Harmonizing satellite CO2 measurements is particularly important since the differences in instruments, observing geometries, sampling strategies, etc. imbue different measurement characteristics in the various satellite CO2 data products. We focus on validating model and satellite observation attributes that impact flux estimates and CO2 assimilation, including accurate error estimates, correlated and random errors, overall biases, biases by season and latitude, the impact of coincidence criteria, validation of seasonal cycle phase and amplitude, yearly growth, and daily variability. We evaluate dry-air mole fraction (XCO2) for Greenhouse gases Observing SATellite (GOSAT) (Atmospheric CO2 Observations from Space, ACOS b3.5) and SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) (Bremen Optimal Estimation DOAS, BESD v2.00.08) as well as the CarbonTracker (CT2013b) simulated CO2 mole fraction fields and the Monitoring Atmospheric Composition and Climate (MACC) CO2 inversion system (v13.1) and compare these to Total Carbon Column Observing Network (TCCON) observations (GGG2012/2014). We find standard deviations of 0.9, 0.9, 1.7, and 2.1 ppm vs. TCCON for CT2013b, MACC, GOSAT, and SCIAMACHY, respectively, with the single observation errors 1.9 and 0.9 times the predicted errors for GOSAT and SCIAMACHY, respectively. We quantify how satellite error drops with data averaging by interpreting according to error2 = a2 + b2/n (with n being the number of observations averaged, a the systematic (correlated) errors, and b the random (uncorrelated) errors). a and b are estimated by satellites, coincidence criteria, and hemisphere. Biases at individual stations have year-to-year variability of  ∼  0.3 ppm, with biases larger than the TCCON-predicted bias uncertainty of 0.4 ppm at many stations. We find that GOSAT and CT2013b underpredict the seasonal cycle amplitude in the Northern Hemisphere (NH) between 46 and 53° N, MACC overpredicts between 26 and 37° N, and CT2013b underpredicts the seasonal cycle amplitude in the Southern Hemisphere (SH). The seasonal cycle phase indicates whether a data set or model lags another data set in time. We find that the GOSAT measurements improve the seasonal cycle phase substantially over the prior while SCIAMACHY measurements improve the phase significantly for just two of seven sites. The models reproduce the measured seasonal cycle phase well except for at Lauder_125HR (CT2013b) and Darwin (MACC). We compare the variability within 1 day between TCCON and models in JJA; there is correlation between 0.2 and 0.8 in the NH, with models showing 10–50 % the variability of TCCON at different stations and CT2013b showing more variability than MACC. This paper highlights findings that provide inputs to estimate flux errors in model assimilations, and places where models and satellites need further investigation, e.g., the SH for models and 45–67° N for GOSAT and CT2013b.

scholarly journals Entropy-Based Research on Precipitation Variability in the Source Region of China’s Yellow River

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2486
Author(s):  
Henan Gu ◽  
Zhongbo Yu ◽  
Guofang Li ◽  
Jian Luo ◽  
Qin Ju ◽  
...  
Keyword(s):  
Hydrological Cycle ◽  
Yellow River ◽  
Source Region ◽  
Monthly Precipitation ◽  
The Tibetan Plateau ◽  
Wet Season ◽  
Climatic Trend ◽  
Moisture Supply ◽  
Increasing Trend

The headwater regions in the Tibetan Plateau play an essential role in the hydrological cycle, however the variation characteristics in the long-term precipitation and throughout-the-year apportionment remain ambiguous. To investigate the spatio-temporal variability of precipitation in the source region of the Yellow River (SRYR), different time scale data during 1979–2015 were studied based on Shannon entropy theory. Long-term marginal disorder index (LMDI) was defined to evaluate the inter-annual hydrologic budget for annual (AP) and monthly precipitation (MP), and annual marginal disorder index (AMDI) to measure intra-annual moisture supply disorderliness for daily precipitation (DP). Results reveal that the AP over the SRYR exhibits remarkable variation, with an inclination rate of 2.7 mm/year, and a significant increasing trend. The climatic trend reversed from warm–dry to warm–wet around the turn of this century. The start of the wet season has advanced from May instead of June, supported by the proportion of MP in AP and the LMDI for May are both comparable with the values during June–September. May contributes the main changes in AP, as it is the only month in the wet season which shows a significant increasing trend during 1979–2015, and has a value in the LMDI that divides the basin in half spatially, the same as AP, with a high value in the northwest and low in the southeast. The AMDI roughly rises with latitude in spatial distribution, with wetlands and glaciers disturbing the continuity of the pattern for a relatively perennial moisture supply. AP has increased on northwest high-altitude areas first and then the southern corner since the beginning of this century. Wetting is mainly attributed to the enhanced southwest monsoon and the warming-induced freeze-thaw process. Meanwhile, AMDI variation concentrated on the Zoige Plateau Wetland, the headwater corner, the summit and part of the North Slope in the Bayan Har Mountain, as a result of a single or combined effect of global climate change and human protection.

scholarly journals Monitoring Vegetation Greenness in Response to Climate Variation along the Elevation Gradient in the Three-River Source Region of China

2021 ◽  
Vol 10 (3) ◽  
pp. 193
Author(s):  
Zhaoqi Wang ◽  
Xiang Liu ◽  
Hao Wang ◽  
Kai Zheng ◽  
Honglin Li ◽  
...  
Keyword(s):  
Vegetation Index ◽  
Source Region ◽  
Elevation Gradient ◽  
Climate Variation ◽  
Mean Annual Precipitation ◽  
Near Infrared Reflectance ◽  
Area Index ◽  
Vegetation Greenness ◽  
The Mean ◽  
The Impact

The Three-River Source Region (TRSR) is vital to the ecological security of China. However, the impact of global warming on the dynamics of vegetation along the elevation gradient in the TRSR remains unclear. Accordingly, we used multi-source remote sensing vegetation indices (VIs) (GIMMS (Global Inventory Modeling and Mapping Studies) LAI (Leaf Area Index), GIMMS NDVI (Normalized Difference Vegetation Index), GLOBMAP (Global Mapping) LAI, MODIS (Moderate Resolution Imaging Spectroradiometer) EVI (Enhanced Vegetation Index), MODIS NDVI, and MODIS NIRv (near-infrared reflectance of vegetation)) and digital elevation model data to study the changes of VGEG (Vegetation Greenness along the Elevation Gradient) in the TRSR from 2001 to 2016. Results showed that the areas with a positive correlation of vegetation greenness and elevation accounted for 36.34 ± 5.82% of the study areas. The interannual variations of VGEG showed that the significantly changed regions were mainly observed in the elevation gradient of 4–5 km. The VGEG was strongest in the elevation gradient of 4–5 km and weakest in the elevation gradient of >5 km. Correlation analysis showed that the mean annual temperature was positively correlated with VIs, and the effect of the mean annual precipitation on VIs was more obvious at low altitude than in high altitude. This study contributes to our understanding of the VGEG variation in the TRSR under global climate variation and also helps in the prediction of future carbon cycle patterns.

scholarly journals A new Geoengineering Model Intercomparison Project (GeoMIP) experiment designed for climate and chemistry models

2014 ◽  
Vol 7 (4) ◽  
pp. 5447-5464 ◽  
Author(s):  
S. Tilmes ◽  
M. J. Mills ◽  
U. Niemeier ◽  
H. Schmidt ◽  
A. Robock ◽  
...  
Keyword(s):  
Model Comparison ◽  
Stratospheric Aerosol ◽  
Atmospheric Composition ◽  
Model Intercomparison ◽  
Data Set ◽  
Aerosol Forcing ◽  
Input Dataset ◽  
Intercomparison Project ◽  
Total Burden ◽  
The Impact

Abstract. A new Geoengineering Model Intercomparison Project (GeoMIP) experiment "G4 specified stratospheric aerosols" (short name: G4SSA) is proposed to investigate the impact of stratospheric aerosol geoengineering on atmospheric composition, climate, and the environment. In contrast to the earlier G4 GeoMIP experiment, which requires an emission of sulphur dioxide (SO2) into the model, a prescribed aerosol forcing file is provided to the community, to be consistently applied to future model experiments between 2020 and 2100. This stratospheric aerosol distribution, with a total burden of about 2 Tg S has been derived using the ECHAM5-HAM microphysical model, based on a continuous annual tropical emission of 8 Tg SO2 year−1. A ramp-up of geoengineering in 2020 and a ramp-down in 2070 over a period of two years are included in the distribution, while a background aerosol burden should be used for the last 3 decades of the experiment. The performance of this experiment using climate and chemistry models in a multi-model comparison framework will allow us to better understand the significance of the impact of geoengineering and the abrupt termination after 50 years on climate and composition of the atmosphere in a changing environment. The zonal and monthly mean stratospheric aerosol input dataset is available at https://www2.acd.ucar.edu/gcm/geomip-g4-specified-stratospheric-aerosol-data-set.

Azimuth estimation capabilities of the ARCESS regional seismic array

1993 ◽  
Vol 83 (4) ◽  
pp. 1213-1231
Author(s):  
Dorthe B. Carr
Keyword(s):  
Time Window ◽  
Source Region ◽  
Event Data ◽  
Small Aperture ◽  
Data Set ◽  
Low Frequencies ◽  
Source Regions ◽  
The Mean ◽  
Local Geology ◽  
Regional Arrays

Abstract The effect of local geology and noise conditions on the performance of a small regional array is investigated by comparing the regional Pn backazimuth estimation capabilities of the ARCESS array in northern Norway to the NORESS array. A broadband frequency-wavenumber estimator was used to calculate backazimuths from the Pn arrival for each of 203 regional events recorded at ARCESS while varying element spacing, frequency band, and time window. Most of the errors in backazimuth are less than 20° when appropriate parameter combinations are used, and mean backazimuth errors are close to zero. The best results are obtained using a 13-element configuration that has a 1.4 km aperture and a maximum station spacing of about 600 m. With the 13-element configuration and the data filtered to include frequencies between 3 and 10 Hz, the mean errors for the 203 event data set are less than 0.9°, and S.D. are as small as 16.9°. There are differences seen in the backazimuth estimation capabilities of ARCESS and NORESS with specific parameter combinations. The larger aperture configurations (10- and 17-elements) have smaller means at ARCESS, although the precision is about the same. The estimates using unfiltered data at ARCESS are poor, because of local noise conditions that increase the level of background noise at low frequencies. Overall the precision is better at NORESS, but both regional arrays have the best results using the 13-element configuration and filtering the data in the middle frequency range (3 to 10 Hz). Other factors investigated include SNR and source region. Backazimuth estimation statistics improve if only events with 5 dB of SNR are included in the data set at both ARCESS and NORESS. The mean errors move closer to zero and standard deviations decrease. The differences between the two arrays are not as pronounced. There are some path effects from different source regions around the ARCESS array. However, combinations of small aperture configurations and middle (3 to 10 Hz) frequency bands work well for events over the entire distance range of 30 to 1200 km. ARCESS and NORESS have similar backazimuth estimation capabilities even though there are differences in the local geology and noise conditions. Because a 13-element configuration produces reliable results for both arrays, it would be reasonable to reduce the number of elements in a regional array. This in turn will reduce the costs associated with building and deploying small regional arrays.

scholarly journals <sup>10</sup>Be systematics in the Tsangpo-Brahmaputra catchment: the cosmogenic nuclide legacy of the eastern Himalayan syntaxis

2017 ◽  
Author(s):  
Maarten Lupker ◽  
Jérôme Lavé ◽  
Christian France-Lanord ◽  
Marcus Christl ◽  
Didier Bourlès ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Sediment Flux ◽  
Coarse Grained ◽  
The Tibetan Plateau ◽  
Data Set ◽  
Denudation Rate ◽  
Cosmogenic Nuclide ◽  
Denudation Rates ◽  
The Impact ◽  
Eastern Himalayan Syntaxis

Abstract. The Tsangpo-Brahmaputra River drains the eastern part of the Himalayan range, flowing from the Tibetan Plateau through the eastern Himalayan syntaxis and downstream to the Indo-Gangetic floodplain. As such it is a unique natural laboratory to study how denudation and sediment production processes are transferred to river detrital signals. In this study, we present a new 10Be data set to constrain denudation rates across the catchment and to quantify the impact of rapid erosion within the syntaxis region on cosmogenic nuclide budgets and signals. 10Be denudation rates span around two orders of magnitude across the catchments (ranging from 0.03 mm/yr to > 4 mm/yr) and sharply increase as the Tsangpo-Brahmaputra flows across the eastern Himalaya. The increase in denudation rates however occurs ~ 150 km downstream of the Namche Barwa-Gyala Peri massif (NBGPm), an area which has been previously characterized by extremely high erosion and exhumation rates. We suggest that this downstream lag is mainly due to the physical abrasion of coarse grained, low 10Be concentration, landslide material produced within the syntaxis that dilutes the upstream high concentration 10Be flux from the Tibetan Plateau only after abrasion has transferred sediment to the studied sand fraction. A simple abrasion model produces typical lag distances of 50 to 150 km compatible with our observations. Abrasion effects reduce the spatial resolution over which denudation can be constrained in the eastern Himalayan syntaxis. In addition, we also highlight that denudation rate estimates are dependent on the sediment connectivity, storage and quartz content of the upstream Tibetan Plateau part of the catchment which tends to lead to an overestimation of downstream denudations rates. Taking these effects into account we estimate a denudation rates of ca. 2 to 5 mm/yr for the entire syntaxis and ca. 4 to 28 mm/yr for the NBGPm, which is significantly higher than other to other large catchments. Overall, 10Be concentrations measured at the outlet of the Tsangpo-Brahmaputra in Bangladesh suggest a sediment flux between 780 and 1430 Mt/yr equivalent to a denudation rate between 0.7 and 1.2 mm/yr for the entire catchment.

Factors associated with mobility apprehension in persons with lower limb amputation

2020 ◽  
Vol 44 (4) ◽  
pp. 208-214
Author(s):  
Shannon L Mathis
Keyword(s):  
Standard Deviation ◽  
Lower Limb ◽  
Avoidance Behavior ◽  
Pain Catastrophizing ◽  
Lower Limb Amputation ◽  
Limb Amputation ◽  
Walking Ability ◽  
Factors Associated ◽  
The Mean ◽  
The Impact

Background: Factors that are related to mobility apprehension were measured in a sample of persons with lower-limb amputation. Objectives: The purpose was to determine whether intensity, interference, or catastrophizing are associated with mobility apprehension. Study design: Cross-sectional study. Methods: Persons with amputation of a lower limb who were attending a national limb loss conference were recruited to complete a survey. Subjects were administered the Tampa Scale for Kinesiophobia to measure mobility apprehension. The Brief Pain Inventory was administered to quantify the affect of pain on general activity, walking ability, and enjoyment of life. The Pain Catastrophizing Scale was administered to assess the tendency to ruminate and magnify pain sensations. A multivariable linear regression was performed to determine factors associated with mobility apprehension. Results: Fifty-three people with lower-limb amputation participated in the study. The mean (standard deviation) score for mobility apprehension was 34.2 (6.0). Mean (standard deviation) pain intensity and interference scores were 1.6 (1.7) and 2.5 (2.6), respectively. The mean (standard deviation) pain catastrophizing score was 9.1 (10). Pain catastrophizing was the only variable associated with higher mobility apprehension ( β = 0.31, p < 0.001, R2 = 0.32). Results suggest that for every one-point increase in the pain catastrophizing score, mobility apprehension will increase by 0.3 of a point. Conclusion: These preliminary results suggest that pain catastrophizing was related to mobility apprehension in this cohort of persons with lower-limb amputation. This relationship indicates that the exploration of avoidance behaviors, such as pain catastrophizing, may be useful when developing a program for physical rehabilitation. Clinical relevance Pain catastrophizing, an avoidance behavior, may be associated with higher levels of mobility apprehension in persons with major lower-limb amputation. Understanding the impact of fear-avoidance behavior will allow clinicians to identify individuals at risk for poor outcomes following amputation surgery and to develop psychological strategies to complement treatment.

scholarly journals Mechanisms for an Amplified Precipitation Seasonal Cycle in the U.S. West Coast under Global Warming

2019 ◽  
Vol 32 (15) ◽  
pp. 4681-4698 ◽  
Author(s):  
Lu Dong ◽  
L. Ruby Leung ◽  
Jian Lu ◽  
Fengfei Song
Keyword(s):  
West Coast ◽  
Seasonal Cycle ◽  
Hydrological Cycle ◽  
Coupled Model ◽  
Wet Season ◽  
Thermal Contrast ◽  
Budget Analysis ◽  
The Mean ◽  
Underlying Mechanisms ◽  
The U.S

Abstract The mean precipitation along the U.S. West Coast exhibits a pronounced seasonality change under warming. Here we explore the characteristics of the seasonality change and investigate the underlying mechanisms, with a focus on quantifying the roles of moisture (thermodynamic) versus circulation (dynamic). The multimodel simulations from phase 5 of the Coupled Model Intercomparison Project (CMIP5) show a simple “wet-get-wetter” response over Washington and Oregon but a sharpened seasonal cycle marked by a stronger and narrower wet season over California. Moisture budget analysis shows that changes in both regions are predominantly caused by changes in the mean moisture convergence. The thermodynamic effect due to the mass convergence of increased moisture dominates the wet-get-wetter response over Washington and Oregon. In contrast, mean zonal moisture advection due to seasonally dependent changes in land–sea moisture contrast originating from the nonlinear Clausius–Clapeyron relation dominates the sharpened wet season over California. More specifically, the stronger climatological land–sea thermal contrast in winter with warmer ocean than land results in more moisture increase over ocean than land under warming and hence wet advection to California. However, in fall and spring, the future change of land–sea thermal contrast with larger warming over land than ocean induces an opposite moisture gradient and hence dry advection to California. These results have important implications for projecting changes in the hydrological cycle of the U.S. West Coast.

Climatological Biomass Burning CO – Where it comes from and where it goes.

2020 ◽  
Author(s):  
Nikos Daskalakis ◽  
Maria Kanakidou ◽  
Mihalis Vrekoussis ◽  
Laura Gallardo
Keyword(s):  
Biomass Burning ◽  
Transport Model ◽  
Source Region ◽  
Atmospheric Composition ◽  
Anthropogenic Sources ◽  
3 Dimensional ◽  
Source Regions ◽  
The World ◽  
Transport Patterns ◽  
The Impact

&lt;p&gt;Carbon Monoxide (CO) is an important atmospheric trace gas, and among the key O&lt;sub&gt;3&lt;/sub&gt; precursors in the troposphere, alongside NO&lt;sub&gt;x&lt;/sub&gt; and VOCs. It is among the most important sinks of OH radical in the atmosphere, which controls lifetime of CH&lt;sub&gt;4&lt;/sub&gt; &amp;#8212; a major greenhouse gas. Biomass burning sources contribute about 25% to the global emissions of CO, with the remaining CO being either emitted from anthropogenic sources, or being chemically formed in the atmosphere. Because of CO tropospheric lifetime is about two months; it can be transported in the atmosphere thus its sources have a hemispheric impact on atmospheric composition.&lt;/p&gt;&lt;p&gt;The extent of the impact of biomass burning to remote areas of the world through long range transport is here investigated using the global 3-dimensional chemistry transport model TM4-ECPL. For this, tagged biomass burning CO tracers from the 13 different HTAP (land) source regions are used in the model in order to evaluate the contribution of each source region to the CO concentrations in the 170 HTAP receptor regions that originate from biomass burning. The global simulations cover the period 1994&amp;#8212;2015 in order to derive climatological transport patterns for CO and assess the contribution of each of the source regions to each of the receptor regions in the global troposphere. The CO simulations are evaluated by comparison with satellite observations from MOPITT and ground based observations from WDCGG. We show the significant impact of biomass burning emissions to the most remote regions of the world.&lt;/p&gt;

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