Injection Height Research Articles

Pollen dispersal properties of Poaceae and Cyperaceae: First estimates of their absolute pollen productivities

Pollen-trap results from the Swiss Alps 1996–2009 were used to assess the pollen dispersal–deposition properties of Poaceae (grasses) and Cyperaceae (sedges). Dispersal parameter values were investigated for a modified version of the Prentice–Sugita pollen dispersal–deposition model. Appropriate values (i.e. realistic in the field and allowing realistic modelling results) for wind speed are suggested to be in the range of 3–7ms−1 and for pollen an injection height of 0.03–0.1m above the ground. The appropriate range of pollen injection height values for grasses and sedges differs from that of trees in the same area, suggesting different pollen dispersal properties between herbs and trees. In addition, logarithmic weighting of the vegetation was tested as an alternative to the modified Prentice–Sugita model. This yielded very similar results, suggesting that the use of such much simpler approximations of the pollen–vegetation relationship is a plausible alternative. Based on the modified Prentice–Sugita model, absolute pollen productivity for Poaceae was estimated to 7300±400 grains cm−2year−1 (1 SE). The data basis for Cyperaceae is smaller than for Poaceae, but the dispersal parameter values determined as appropriate for Poaceae yield good results. Absolute pollen productivity for Cyperaceae was estimated to 6300±1100 grains cm−2year−1 (1 SE).

Optimization of solvent composition and injection rate in vapour extraction process

Abstract Vapour extraction (VAPEX) is a technique used to enhance heavy oil recovery. Many studies have been carried out on VAPEX on a macro scale since 1989. However, the number of studies conducted on a mega scale is limited. Solvent design and determination of injection rate are two important parameters that have not been clearly defined on a mega scale. In this study, the VAPEX process was simulated for a heavy oil reservoir to determine the optimum solvent injection rate and composition on a mega scale. Propane (C3) ranging from 5 to 50 mol% and butane (C4) from 5 to 40 mol% as solvents were mixed with methane (C1). A method of estimating injection rate on a mega scale was introduced. Furthermore, it was found that porosity, vertical permeability, and bulk volume size did not have a noticeable effect on injection rate, while injection height from reservoir top, injector length, and amount of solvent in the mixture significantly influenced injection rate. It was also observed that higher amounts of solvents in the mixture caused greater reduction in heavy oil viscosity. Conversely, oil recovery values were higher for the mixtures with lower amounts of C3 and C4. Moreover, C4 seemed more effective for heavy oil viscosity reduction than C3, while the oil recovery value by C3 was higher than C4.

Volatiles in subduction zone magmatism

Abstract The volatile cycle at subduction zones is key to the petrogenesis, transport, storage and eruption of arc magmas. Volatiles control the flux of slab components into the mantle wedge, are responsible for melt generation through lowering the solidi of mantle materials, and influence the crystallizing phase assemblages in the overriding crust. Globally, magma ponding depths may be partially controlled by melt volatile contents. Volatiles also affect the rate and extent of degassing during magma storage and decompression, influence magma rheology and therefore control eruption style. The style of eruptions in turn determines the injection height of environmentally sensitive gases into the atmosphere and the impact of explosive arc volcanism. In this overview we summarize recent advances regarding the role of volatiles during slab dehydration, melt generation in the mantle wedge, magmatic evolution in the overriding crust, eruption triggering, and the release of some magmatic volatiles from volcanic edifices into the Earth's atmosphere.

Applicability of an integrated plume rise model for the dispersion from wild-land fires

Abstract. We have presented an overview of a mathematical model, BUOYANT, that was originally designed for the evaluation of the dispersion of buoyant plumes originated from major warehouse fires. The model addresses the variations of the cross-plume integrated properties of a buoyant plume in the presence of a vertically varying atmosphere. The model also includes a treatment for a rising buoyant plume interacting with an inversion layer. We have compared the model predictions with the data of two prescribed wild-land fire experiments. For the SCAR-C experiment in Quinault (US) in 1994, the predicted vertical extents of the plume at maximum plume rise were between 500 and 800 m and between 200 and 700 m, using two alternative meteorological data sets. The corresponding observed injection heights of the aerosol particles measured using an airborne lidar (light detection and ranging) ranged from 250 to 600 m. For the prescribed burning experiment in Hyytiälä (Finland) in 2009, the model predictions were compared with plume elevations and diameters, determined based on particulate matter number concentration measurements onboard an aeroplane. However, the agreement between modelled and measured results substantially depends on how the properties of the source term are evaluated, especially regarding the convective heat fluxes from the fire. The results demonstrate that in field experiments on wild-land fires, there are substantial uncertainties in estimating both (i) the source terms for the atmospheric dispersion computations and (ii) the relevant vertical meteorological profiles.

Heat Transfer Characteristics of Multinozzle Air Impingement Jet during Die Steel Plate Cooling Progress

Aiming at the new die steel quenching equipment, using Fluent software, the effects of the nozzle spacing, height, injection pressure, and comprehensive factors on the heat transfer characteristics are studied. The results show that when the nozzle spacing and injection pressure are given, the heat transfer coefficient increases first and then decreases with the injection height increase, and the cooling uniformity is better; when the injection pressure is given, the injection height increases with the nozzle spacing increase under the maximum heat exchanger capability; when the nozzle spacing is given, the injection height increases with the injection pressure under the maximum heat exchanger capability; for the nozzle arrangement in the paper, there is a relationship between the injection height and nozzle spacing when the heat transfer is uniform, H ≈ 8 S. The results have important reference value for optimization design of the equipment and actual production process.

Constraining CO<sub>2</sub> emissions from open biomass burning by satellite observations of co-emitted species: a method and its application to wildfires in Siberia

Abstract. A method to constrain carbon dioxide (CO2) emissions from open biomass burning by using satellite observations of co-emitted species and a chemistry-transport model (CTM) is proposed and applied to the case of wildfires in Siberia. CO2 emissions are assessed by means of an emission model assuming a direct relationship between the biomass burning rate (BBR) and the fire radiative power (FRP) derived from MODIS measurements. The key features of the method are (1) estimating the FRP-to-BBR conversion factors (α) for different vegetative land cover types by assimilating the satellite observations of co-emitted species into the CTM, (2) optimal combination of the estimates of α derived independently from satellite observations of different species (CO and aerosol in this study), and (3) estimation of the diurnal cycle of the fire emissions directly from the FRP measurements. Values of α for forest and grassland fires in Siberia and their uncertainties are estimated using the Infrared Atmospheric Sounding Interferometer (IASI) carbon monoxide (CO) retrievals and MODIS aerosol optical depth (AOD) measurements combined with outputs from the CHIMERE mesoscale chemistry-transport model. The constrained CO emissions are validated through comparison of the respective simulations with independent data of ground-based CO measurements at the ZOTTO site. Using our optimal regional-scale estimates of the conversion factors (which are found to be in agreement with earlier published estimates obtained from local measurements of experimental fires), the total CO2 emissions from wildfires in Siberia in 2012 are estimated to be in the range from 280 to 550 Tg C, with the optimal (maximum likelihood) value of 392 Tg C. Sensitivity test cases featuring different assumptions regarding the injection height and diurnal variations of emissions indicate that the derived estimates of the total CO2 emissions in Siberia are robust with respect to the modeling options (the different estimates vary within less than 15% of their magnitude). The CO2 emission estimates obtained for several years are compared with independent estimates provided by the GFED3.1 and GFASv1.0 global emission inventories. It is found that our "top-down" estimates for the total annual biomass burning CO2 emissions in the period from 2007 to 2011 in Siberia are by factors of 2.5 and 1.8 larger than the respective bottom-up estimates; these discrepancies cannot be fully explained by uncertainties in our estimates. There are also considerable differences in the spatial distribution of the different emission estimates; some of those differences have a systematic character and require further analysis.

Correcting the record of volcanic stratospheric aerosol impact: Nabro and Sarychev Peak

AbstractSince 2010, several papers have been published that reveal a pattern of discrepancies between stratospheric aerosol data from the Optical Spectrograph and Infrared Imaging System (OSIRIS) instrument and other measurements and model simulations of volcanic plumes from Kasatochi, Sarychev Peak, and Nabro volcanoes. OSIRIS measurements show two discrepancies, a posteruption lag in aerosol onset/increase and a low bias in maximum stratospheric aerosol optical depth. Assumed robustness of the OSIRIS data drove various conclusions, some controversial, such as the contention that the June 2011 Nabro plume was strictly tropospheric, and entered the stratosphere indirectly via the Asian monsoon. Those conclusions were driven by OSIRIS data and a Smithsonian Institution report of strictly tropospheric injection heights. We address the issue of Nabro's eruption chronology and injection height, and the reasons for the OSIRIS aerosol discrepancies. We lay out the time line of Nabro injection height with geostationary image data, and stratospheric plume evolution after eruption onset using retrievals of sulfur dioxide and sulfate aerosol. The observations show that Nabro injected sulfur directly to or above the tropopause upon the initial eruption on 12/13 June and again on 16 June 2011. Next, OSIRIS data are examined for nonvolcanic and volcanically perturbed conditions. In nonvolcanic conditions OSIRIS profiles systematically terminate 1–4 km above the tropopause. Additionally, OSIRIS profiles terminate when 750 nm aerosol extinction exceeds ∼0.0025 km−1, a level that is commonly exceeded after volcanic injections. Our findings largely resolve the discrepancies in published works involving OSIRIS aerosol data and offer a correction to the Nabro injection‐height and eruption chronology.

Injection heights of springtime biomass-burning plumes over peninsular Southeast Asia and their impacts on long-range pollutant transport

Abstract. We analyzed observations from the Multi-angle Imaging SpectroRadiometer (MISR) to determine the injection heights of biomass-burning smoke plumes over peninsular Southeast Asia (PSEA, here defined as Vietnam, Cambodia, Thailand, Laos, and Myanmar) in the spring, with the goal of evaluating the impacts on long-range pollutant transport. We retrieved the heights of 22 000 MISR smoke pixels from 607 smoke plumes over PSEA during February to April of the years 2001–2010. Forty-five percent of the analyzed smoke pixels were above the local mean boundary layer (1 km) at MISR overpass time (10:30 a.m. local time). We used the GEOS–Chem model to simulate the transport of PSEA biomass-burning pollutants in March 2001. On a monthly mean basis, we found that the direct injection of 40% of the PSEA biomass-burning emissions had little impact on the long-range transport of CO to downwind regions, compared to a control simulation where all biomass-burning emissions were released in the boundary layer. This was because CO at the surface over PSEA was efficiently lifted into the free troposphere by deep convection associated with synoptic-scale weather systems. For pollutants with lifetimes shorter than the synoptic timescale, such as black carbon aerosol (BC), their long-range transport was much more sensitive to the initial plume injection height. The direct injection of NOx from PSEA biomass burning into the free troposphere drove increased formation and transport of peroxyacetyl nitrate (PAN), which in turn led to a small increase in ozone over downwind southern China and the northwestern Pacific. The Pacific subtropical high transported BC emitted from PSEA biomass burning to the marine boundary layer over the tropical northwestern Pacific. We compared our model results to aircraft measurements over the northwestern Pacific during the TRACE-P campaign (March 2001). The direct injection of 40% of the PSEA biomass-burning pollutants into the free troposphere in the model led to a more pronounced BC peak at 3 km over the northwestern Pacific. Our analysis highlights the point that the injection heights of smoke plumes presents great uncertainty over the interpretation of BC measurements downwind of biomass-burning regions.

The 2011 Nabro eruption, a SO<sub>2</sub> plume height analysis using IASI measurements

Abstract. In the wake of the June 2011 Nabro eruption, large stratospheric plumes were observed by several instruments up to altitudes of 21 km, much higher than initial reported injection heights. It has been debated whether deep convection associated with the Asian Summer Monsoon anticyclone played a vital role in the vertical transport of the plume. Here we present a new and fast SO2 height retrieval algorithm for observations of the Infrared Atmospheric Sounding Interferometer (IASI). A comprehensive validation with forward trajectories and coincident CALIOP measurements is presented which indicates an accuracy better than 2 km for plumes below 20 km and SO2 columns up to the 1 DU level. We use this new product to analyse the Nabro eruption. Our findings indicate an initial plume located mainly between 15 and 17 km for which the lower parts underwent in succession rapid descent and uplift, within the Asian Monsoon anticyclone circulation, up to the stable thermal tropopause between 16 and 18 km, from where it slowly ascended further into the stratosphere. Evidence is presented that emissions in the first week of the eruption also contributed to the stratospheric sulfur input. This includes a second eruption between 15 and 17 km on the 16th and continuous emissions in the mid-troposphere of which some were also entrained and lifted within the anticyclonic circulation.

Quantifying the potential for high-altitude smoke injection in the North American boreal forest using the standard MODIS fire products and subpixel-based methods

All chemical transport models require an estimation of the vertical distribution of smoke particles near the source. This study quantitatively examines the strengths and weaknesses of several fire products for characterizing plume buoyancy and injection heights in the North American boreal forest during 2004–2005. Observations from the Multiangle Imaging Spectroradiometer show that 21% of smoke plumes are injected more than 500 m above the boundary layer (BL500) and 8% exceed 2.5 km above ground level. Corresponding observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) show that probability of injection above the BL500 exceeds 60% for pixel-based fire radiative power (FRPp) values above ~2500 MW. Increasing values of subpixel-retrieved fire area and temperature also correspond to higher injections but only after removing fire pixels with a weak 11 µm fire signal and clustering. The probability of injection above the BL500 reaches 50% when the subpixel radiant flux (FRPf flux) exceeds 20 kW/m2, highlighting its potential for estimating plume buoyancy. However, these data have limitations similar to FRPp, where the highest probability of injection corresponds to a small percentage of the data set (5–18%), and many high-altitude injections occur with lower values. Examinations of individual smoke plumes highlight the importance of combining pixel-level and subpixel outputs and show that plume injection is also sensitive to the fire pixel spatial distribution and meteorology. Therefore, an optimal method for predicting high-altitude injections will require some combination of injection climatology, FRPp, FRPf flux, and meteorology, but each variable's importance will depend on fire event characteristics.

Automated Stereo Retrieval of Smoke Plume Injection Heights and Retrieval of Smoke Plume Masks From AATSR and Their Assessment With CALIPSO and MISR

The longevity and dispersion of smoke and associated chemical constituents released from wildfire events are dependent on several factors, crucially including the height at which the smoke is injected into the atmosphere. The aim here is to provide improved emission data for the initialization of chemical transport models in order to better predict aerosol and trace gas dispersion following injection into the free atmosphere. A new stereo-matching algorithm, named M6, which can effectively resolve smoke plume injection heights (SPIH), is presented here. M6 is extensively validated against two alternative spaceborne earth observation SPIH data sources and demonstrates good agreement. Further, due to the spectral and dual-view configuration of the Advanced Along-Track Scanning Radiometer imaging system, it is possible to automatically differentiate smoke from other atmospheric features effectively-a feat, which currently no other algorithm can achieve. Additionally, as the M6 algorithm shares a heritage with the other M-series matchers, it is here compared against one of its predecessors, M4, which, for the determination of SPIH, M6 is shown to substantially outperform.

Thermal Field of Twin Variably Elevated Tandem Jets in Crossflow

Consideration is given to twin inline elliptical fume jets issuing within an oncoming cooler environmental crossflow. Jets are emitted from similar nozzles, characterized by a variable injection height. Such a configuration is found at large scale, in the industrial urban zones, and more particularly in multiple chimney power plants. It is found at small scale as well like in cooling in electronic devices. The present study is carried out numerically by means of the finite volume method together with the Reynolds Stress Model (RSM) second order turbulent closure model and non uniform grid system particularly refined around the emitting nozzles. Emphasis is put on the temperature distribution around the emitting nozzles in order to highlight the joint effect of the jets elevation and temperature. It was mainly found that both parameters are complementary and help straitening the discharged jets, leading their thermal mixing away from the injection ground. Nomenclature

Modelling dispersion of smoke from wildfires in a Mediterranean area

We present a modelling system for the estimation of forest fire emissions ( prebolchem-fire ) and their inclusion in the atmospheric composition model BOLCHEM. Emission fluxes have been estimated following the methodology proposed by Seiler and Crutzen (1980) and using MODIS ‘burned area product’. Then they are modulated following the WRAP approach (WRAP, 2005). This approach is also used for the estimations of fire emission height. Model simulations have been performed for the period 22–30 August 2007, in which fires were most severe in Greece, Albania and Algeria. The estimated emission fluxes have been compared with those estimated by the global model FINNv1 (fire inventory from NCAR) and the difference between the two emissions have been discussed. The modelled concentration of black carbon aerosol is compared with measurements at PEARL station lidar, Tito Scalo, Potenza (40.63°N, 15.80°E, 760 m asl), Italy, on 30 August 2007. We discuss the discrepancies between the measured and modelled vertical distribution concentrations of black carbon aerosol, probably due to uncertainties related to the estimation of the total flux and of the injection height of the smoke.

Determination of Ferulic Acid in “AI-FU-NUAN-GONG” Pills by High Performance Capillary Electrophoresis

High performance capillary zone electrophoresis (HPCE) was used in this text to determine the content of ferulic acid in a ready-made Chinese herbal medicine called AI-FUNUAN-GONG (in pills). Electrophoretic separation conditions: Uncoated fused silica capillary column (75um×49/58cm), injection height 7.5cm, 30mmolL-1 borax solution, separation voltage 20kV, injection time 10s, detection wavelength 315 nm, experimental temperature 20°C.Linearity was kept in the concentration ranging from 1~62.5 mg·L-1 of ferulic acid with correlation coefficient of 0.970. The average recovery was 97.541% and RSD value was 6.57%. Sample content of ferulic acid was 0.0715mg/g. This method has the advantages of strong specificity, simpleness, speediness, accurate results and good repeatability in separation and it is useful for determination of ferulic Acid in AI-FU-NUAN-GONG Pills.

Determination of Ferulic Acid in“SHI-QUAN-DA-BU” Pills by High Performance Capillary Electrophoresis

High performance capillary electrophoresis (HPCE) was used in this text to determine the content of ferulic acid in “SHI-QUAN-DA-BU” Pills. Electrophoretic separation conditions: Uncoated fused silica capillary column(75um×49/58cm), injection height 7.5cm, 30mmol•L-1borax solution, separation voltage 20kV, injection time 15s, detection wavelength 315 nm, experimental temperature 20°C. Linearity was kept in the concentration ranging from 1~31.25 mg·L-1of ferulic acid with correlation coefficient of 0.970. The average recovery was 97.56% and RSD value was 6.4%. The content of ferulic acid was 0.0855 mg/g (n=6).

Mesoscale modeling and satellite observation of transport and mixing of smoke and dust particles over northern sub‐Saharan African region

AbstractThe transport and vertical distribution of smoke and dust aerosols over the northern sub‐Saharan African region are simulated in the Weather Research and Forecasting model with Chemistry (WRF‐Chem), which uses hourly dynamic smoke emissions from the Fire Locating and Modeling of Burning Emissions database derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) fire products. Model performance for February 2008 is evaluated using MODIS true color images, aerosol optical depth (AOD) measurements from the Aerosol Robotic Network, MODIS AOD retrievals, and the Cloud‐Aerosol Lidar data with Orthogonal Polarization (CALIOP) atmospheric backscattering and extinction products. Specification of smoke injection height of 650 m in WRF‐Chem yields aerosol vertical profiles that are most consistent with CALIOP observations of aerosol layer height. Between the equator and 10°N, Saharan dust is often mixed with smoke near the surface, and their transport patterns manifest the interplay of trade winds, subtropical highs, precipitation associated with the Intertropical Convergence Zone, and the high mountains located near the Great Rift Valley region. At the 700 hPa level and above, smoke layers spread farther to the north and south and are often above the dust layers over the Sahel region. In some cases, transported smoke can also be mixed with dust over the Saharan region. Statistically, 5% of the CALIOP valid measurements in February 2007–2011 show aerosol layers either above or between the clouds, reinforcing the importance of the aerosol vertical distribution for quantifying aerosol impact on climate in the Sahel region.

Volcanic sulfur dioxide plume forecasts based on UV satellite retrievals for the 2011 Grímsvötn and the 2010 Eyjafjallajökull eruption

AbstractThe sulfur dioxide plumes released by the eruptions of the Icelandic volcanoes Eyjafjallajökull in May 2010 and Grímsvötn in May 2011 were studied using satellite observations from the Second Global Ozone Monitoring Experiment (GOME‐2), Ozone Monitoring Instrument (OMI), and Scanning Imaging Absorption Spectrometer for Atmospheric Chartography and modeled with the Integrated Forecasting System of the European Centre for Medium‐Range Weather Forecasts (ECMWF). The retrievals of SO2 total columns (TCSO2) were (i) used to estimate emission rate and injection height of the two eruptions and (ii) assimilated with ECMWF's four‐dimensional variational data assimilation algorithm to obtain initial conditions for subsequent forecasts. The OMI retrievals provided the highest plume observation values, and GOME‐2 had the best coverage. The emission parameters were estimated by comparing TCSO2 observations with an ensemble of test tracers injected at different heights. The applied methodology led to emission estimates of 0.25 Tg over 20 days in May 2010 and 0.32 Tg over 2 days in May 2011. The SO2 analyses produced by assimilating GOME‐2 TCSO2 retrievals captured the plume maxima well but exaggerated the plume area. The injection height estimate was used during the assimilation to determine the height of the assimilated plume. Plume forecasts were evaluated by means of hit‐rate and plume‐size statistics for different TCSO2 thresholds. Plume forecasts using either the emission parameters or the SO2 analyses as initial conditions agreed reasonably with the observations, but using both led to the best forecast performance. The initialization with SO2 analysis fields improved, in particular, the forecast of the Grímsvötn plume after the end of the eruption. The developed forecast and assimilation system can be applied for near–real‐time forecasting of volcanic SO2 plumes.

Simulations of the transport and deposition of <sup>137</sup>Cs over Europe after the Chernobyl Nuclear Power Plant accident: influence of varying emission-altitude and model horizontal and vertical resolution

Abstract. The coupled model LMDZORINCA has been used to simulate the transport, wet and dry deposition of the radioactive tracer 137Cs after accidental releases. For that reason, two horizontal resolutions were deployed and used in the model, a regular grid of 2.5° × 1.27°, and the same grid stretched over Europe to reach a resolution of 0.66° × 0.51°. The vertical dimension is represented with two different resolutions, 19 and 39 levels respectively, extending up to the mesopause. Four different simulations are presented in this work; the first uses the regular grid over 19 vertical levels assuming that the emissions took place at the surface (RG19L(S)), the second also uses the regular grid over 19 vertical levels but realistic source injection heights (RG19L); in the third resolution the grid is regular and the vertical resolution 39 levels (RG39L) and finally, it is extended to the stretched grid with 19 vertical levels (Z19L). The model is validated with the Chernobyl accident which occurred in Ukraine (ex-USSR) on 26 May 1986 using the emission inventory from Brandt et al. (2002). This accident has been widely studied since 1986, and a large database has been created containing measurements of atmospheric activity concentration and total cumulative deposition for 137Cs from most of the European countries. According to the results, the performance of the model to predict the transport and deposition of the radioactive tracer was efficient and accurate presenting low biases in activity concentrations and deposition inventories, despite the large uncertainties on the intensity of the source released. The best agreement with observations was obtained using the highest horizontal resolution of the model (Z19L run). The model managed to predict the radioactive contamination in most of the European regions (similar to De Cort et al., 1998), and also the arrival times of the radioactive fallout. As regards to the vertical resolution, the largest biases were obtained for the 39 layers run due to the increase of the levels in conjunction with the uncertainty of the source term. Moreover, the ecological half-life of 137Cs in the atmosphere after the accident ranged between 6 and 9 days, which is in good accordance to what previously reported and in the same range with the recent accident in Japan. The high response of LMDZORINCA model for 137Cs reinforces the importance of atmospheric modelling in emergency cases to gather information for protecting the population from the adverse effects of radiation.

Impact of the vertical emission profiles on background gas-phase pollution simulated from the EMEP emissions over Europe

Abstract. Five one-year air quality simulations over a domain covering Europe have been performed using the CHIMERE chemistry transport model and the EMEP emission dataset for Europe. These five simulations differ only by the representation of the effective emission heights for anthropogenic emissions: one has been run using the EMEP standard recommendations, three others with vertical injection profiles derived from the EMEP recommendations but multiplying the injection height by 0.75, 0.50 and 0.25, respectively, while the last one uses vertical profiles derived from the recent literature. It is shown that using injection heights lower than the EMEP recommendations leads to significantly improved simulation of background SO2, NO2 and O3 concentrations when compared to the Airbase station measurements.

How much CO was emitted by the 2010 fires around Moscow?

Abstract. The fires around Moscow in July and August 2010 emitted a large amount of pollutants to the atmosphere. Here we estimate the carbon monoxide (CO) source strength of the Moscow fires in July and August by using the TM5-4DVAR system in combination with CO column observations of the Infrared Atmospheric Sounding Interferometer (IASI). It is shown that the IASI observations provide a strong constraint on the total emissions needed in the model. Irrespective of the prior emissions used, the optimised CO fire emission estimates from mid-July to mid-August 2010 amount to approximately 24 Tg CO. This estimate depends only weakly (< 15%) on the assumed diurnal variations and injection height of the emissions. However, the estimated emissions might depend on unaccounted model uncertainties such as vertical transport. Our emission estimate of 22–27 Tg CO during roughly one month of intense burning is less than suggested by another recent study, but substantially larger than predicted by the bottom-up inventories. This latter discrepancy suggests that bottom-up emission estimates for extreme peat burning events require improvements.