scholarly journals Ozone Forecasts of the Stratospheric Polar Vortex–Splitting Event in September 2002

2005 ◽  
Vol 62 (3) ◽  
pp. 812-821 ◽  
Author(s):  
Henk Eskes ◽  
Arjo Segers ◽  
Peter van Velthoven
Keyword(s):  
Total Ozone ◽  
European Space Agency ◽  
Polar Vortex ◽  
Forecast Model ◽  
Tracer Transport ◽  
Good Correspondence ◽  
Stratospheric Polar Vortex ◽  
Ozone Forecast ◽  
Space Agency ◽  
Assimilation Model

Abstract The Southern Hemisphere major warming event in September 2002 has led to a breakup of the vortex in the middle and higher stratosphere and to a corresponding splitting of the ozone hole. Daily 3D ozone forecasts, produced at the Royal Netherlands Meteorological Institute (KNMI) with a tracer transport and assimilation model based on the ECMWF dynamical forecasts, provided an accurate prediction of this event a week prior to the actual breakup of the vortex. The ozone forecast model contains parameterizations for gas phase and heterogeneous chemistry. Initial states for the forecast are obtained from the assimilation of near-real-time ozone data from the Global Ozone Monitoring Experiment (GOME) on European Space Agency (ESA) Remote Sensing Satellite-2 (ERS-2). In this paper, the ozone forecasts and analyses are discussed as produced before, during, and after the event. These fields are compared with ground-based Dobson, ozonesonde, and Total Ozone Mapping Spectrometer (TOMS) observations. The total ozone comparisons show that the location of the vortex edge is generally well described by the 5–7-day forecasts in September and October. The GOME assimilation compared with TOMS shows a good correspondence concerning vortex location and ozone features but also reflects clear differences in the average ozone amount between the two retrieval schemes. The assimilation system produces realistic ozone profiles, apart from a systematic underestimation of ozone around 150 hPa inside the vortex in August–October.

An Observational Study of the Final Breakdown of the Southern Hemisphere Stratospheric Vortex in 2002

2005 ◽  
Vol 62 (3) ◽  
pp. 735-747 ◽  
Author(s):  
Yvan J. Orsolini ◽  
Cora E. Randall ◽  
Gloria L. Manney ◽  
Douglas R. Allen
Keyword(s):  
Southern Hemisphere ◽  
Vortex Core ◽  
Vortex Breakdown ◽  
Michelson Interferometer ◽  
European Space Agency ◽  
Polar Vortex ◽  
Stratospheric Aerosol ◽  
Satellite Observations ◽  
Stratospheric Polar Vortex ◽  
Space Agency

Abstract The 2002 Southern Hemisphere final warming occurred early, following an unusually active winter and the first recorded major warming in the Antarctic. The breakdown of the stratospheric polar vortex in October and November 2002 is examined using new satellite observations from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument aboard the European Space Agency (ESA) Environment Satellite (ENVISAT) and meteorological analyses, both high-resolution fields from the European Centre for Medium-Range Weather Forecasts and the coarser Met Office analyses. The results derived from MIPAS observations are compared to measurements and inferences from well-validated solar occultation satellite instruments [Halogen Occultation Experiment (HALOE), Polar Ozone and Aerosol Measurement III (POAM III), and Stratospheric Aerosol and Gas Experiments II and III (SAGE II and III)] and to finescale tracer fields reconstructed by transporting trace gases based on MIPAS or climatological data using a reverse-trajectory method. These comparisons confirm the features in the MIPAS data and the interpretation of the evolution of the flow during the vortex decay revealed by those features. Mapped ozone and water vapor from MIPAS and the analyzed isentropic potential vorticity vividly display the vortex breakdown, which occurred earlier than usual. A large tongue of vortex air was pulled out westward and coiled up in an anticyclone, while the vortex core remnant shrank and drifted eastward and equatorward over the South Atlantic. By roughly mid-November, the vortex remnant at 10 mb had shrunk below scales resolved by the satellite observations, while a vortex core remained in the lower stratosphere.

scholarly journals Six years of total ozone column measurements from SCIAMACHY nadir observations

2009 ◽  
Vol 2 (1) ◽  
pp. 87-98 ◽  
Author(s):  
C. Lerot ◽  
M. Van Roozendael ◽  
J. van Geffen ◽  
J. van Gent ◽  
C. Fayt ◽  
...  
Keyword(s):  
Cross Sections ◽  
Total Ozone ◽  
Large Scale ◽  
European Space Agency ◽  
Data Sets ◽  
Data Set ◽  
Ozone Data ◽  
Space Agency ◽  
German Aerospace ◽  
The Impact

Abstract. Total O3 columns have been retrieved from six years of SCIAMACHY nadir UV radiance measurements using SDOAS, an adaptation of the GDOAS algorithm previously developed at BIRA-IASB for the GOME instrument. GDOAS and SDOAS have been implemented by the German Aerospace Center (DLR) in the version 4 of the GOME Data Processor (GDP) and in version 3 of the SCIAMACHY Ground Processor (SGP), respectively. The processors are being run at the DLR processing centre on behalf of the European Space Agency (ESA). We first focus on the description of the SDOAS algorithm with particular attention to the impact of uncertainties on the reference O3 absorption cross-sections. Second, the resulting SCIAMACHY total ozone data set is globally evaluated through large-scale comparisons with results from GOME and OMI as well as with ground-based correlative measurements. The various total ozone data sets are found to agree within 2% on average. However, a negative trend of 0.2–0.4%/year has been identified in the SCIAMACHY O3 columns; this probably originates from instrumental degradation effects that have not yet been fully characterized.

scholarly journals Climatological features of stratospheric streamers in the FUB-CMAM with increased horizontal resolution

2004 ◽  
Vol 4 (5) ◽  
pp. 6789-6822
Author(s):  
K. Krüger ◽  
U. Langematz ◽  
J. L. Grenfell ◽  
K. Labitzke
Keyword(s):  
East Asia ◽  
Total Ozone ◽  
Large Scale ◽  
Middle Atmosphere ◽  
Polar Vortex ◽  
Horizontal Resolution ◽  
Transport Processes ◽  
The Arctic ◽  
Future Climate Change ◽  
Good Correspondence

Abstract. The purpose of this study is to investigate horizontal transport processes in the winter stratosphere using data with a high spatial and temporal resolution. For this reason the Freie Universität Berlin Climate Middle Atmosphere Model (FUB-CMAM) with its model top at 83 km altitude, increased horizontal resolution T42 and the semi-Lagrangian transport scheme for advecting passive tracers is used. A new result of this paper is the classification of specific transport phenomena within the stratosphere into tropical-subtropical streamer (e.g. Offermann et al., 1999) and polar vortex extrusions hereafter called polar vortex streamers. To investigate the role played by these large-scale structures on the inter-annual and seasonal variability of the observed negative ozone trend in northern mid-latitudes, the global occurrence of such streamers were calculated based on a 10-year model climatology, concentrating on the existence of the Arctic polar vortex. For the identification and counting of streamers, the new method of zonal anomaly was chosen, which in comparison to other methods produced the best result in this study. The analysis of the months October–May yielded a maximum occurrence of tropical-subtropical streamers during Arctic winter and spring in the middle and upper stratosphere. Synoptic maps revealed highest intensities in the subtropics over East Asia with a secondary maximum over the Atlantic in the northern hemisphere. Furthermore, tropical-subtropical streamers exhibited about a four times higher occurrence than polar vortex streamers, indicating that the subtropical barrier is more permeable than the polar vortex barrier (edge) in the model, which is in good correspondence with observations (e.g. Plumb, 2002; Neu et al., 2003). Interesting for the total ozone loss in mid-latitudes is the consideration of the lower stratosphere, where strongest ozone depletion is observed at polar latitudes (WMO, 2003). In this particular region the FUB-CMAM simulated a climatological maximum of 10% occurrence of tropical-subtropical streamers over East-Asia/West Pacific and the Atlantic during early- and mid-winter. The results of this paper demonstrate that the regular occurrence of stratospheric streamers e.g., large-scale mixing processes of tropical-subtropical and polar vortex air masses into mid-latitudes, could play a significant role on the strength and variability of the observed total ozone decrease at mid-latitudes and should not be neglected in future climate change studies.

scholarly journals The January 2006 low ozone event over the UK

2006 ◽  
Vol 6 (5) ◽  
pp. 8457-8483 ◽  
Author(s):  
M. Keil ◽  
D. R. Jackson ◽  
M. C. Hort
Keyword(s):  
Total Ozone ◽  
Stratospheric Ozone ◽  
Polar Vortex ◽  
British Isles ◽  
Stratospheric Polar Vortex ◽  
North West ◽  
Total Ozone Column ◽  
Mixing Ratios ◽  
The Uk ◽  
Ozone Column

Abstract. A record low total ozone column of 177 DU was observed at Reading, UK, on 19 January 2006. Low ozone values were also recorded at other stations in the British Isles and North West Europe on, and around, this date. Hemispheric maps of total ozone from the World Meteorological Organisation (WMO) Ozone Mapping Centre also show the evolution of this ozone minimum from 15–20 January 2006 over North West Europe. Ozonesonde measurements made at Lerwick, UK, show that ozone mixing ratios in the mid-stratosphere on 18 January are around 1–2 ppmv lower than both climatology and observations made one and two weeks prior to this date. In addition, ozone mixing ratios in the UTLS region were also noticeably reduced on 18 January. Analysis of the ozonesonde observations indicate that the mid-stratosphere ozone accounts for around a third of the reduction in total ozone column measurements while the UTLS ozone values account for two thirds of the depletion. It is evident from the ozonesonde data that ozone loss is occuring at two distinct vertical regions. Met Office analyses indicate that stratospheric polar vortex temperatures were cold enough for Polar Stratospheric Cloud (PSC) formation during 14 days in January prior to the low ozone event on 19 January. The presence of PSCs is confirmed by observations from the Scanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY). As a consequence of a stratospheric sudden warming that was in progress during January 2006, the polar vortex was shifted southwards over northwest Europe. This includes a period from 16 to 19 January where PSCs were present in the vortex over the UK. Throughout most of January suitable conditions were present for ozone destruction by heterogenous chemistry within the polar vortex. Evidence from Lerwick and Sodankylä ozonesonde profiles, and maps of Ertel's potential vorticity calculated from Met Office analyses, strongly suggests that the air inside the stratospheric vortex was poor in ozone for at least one week prior to 18 January. It is also possible that local chemical destruction of stratospheric ozone further contributed to the record low ozone observed at Reading. A closer examination of the WMO total ozone maps shows that the daily minima are often of synoptic, rather than planetary, scale. This therefore suggests a tropospheric, rather than stratospheric, mechanism for the ozone minima. Moderate total ozone depletion is commonly observed in the northern hemisphere middle and high latitude winter. This depletion is related to the lifting of the tropopause associated with the presence of an upper troposphere/lower stratosphere anticyclone. We show a strong link between the ozone minima in the WMO maps and 100 hPa geopotential height from Met Office analyses, and therefore it appears that this may also be a plausible mechanism for the record low ozone column that is observed. Back trajectories calculated by the Met Office NAME III model show that air parcels in the mid-stratosphere do arrive over the British Isles on 19 January via the polar vortex. The NAME III model results also show that air parcels near the tropopause arrive from low latitudes and are transported anticyclonically. Therefore this strongly suggests that the record low ozone values are due to a combination of a raised tropopause and the presence of low ozone stratospheric air aloft.

scholarly journals Parameterization of middle atmospheric water vapor photochemistry for high-altitude NWP and data assimilation

2008 ◽  
Vol 8 (4) ◽  
pp. 13999-14032 ◽  
Author(s):  
J. P. McCormack ◽  
K. W. Hoppel ◽  
D. E. Siskind
Keyword(s):  
Water Vapor ◽  
Middle Atmosphere ◽  
Transport Model ◽  
Polar Vortex ◽  
Forecast Model ◽  
Stratospheric Polar Vortex ◽  
One Dimensional ◽  
Sources And Sinks ◽  
Free Running ◽  
The One

Abstract. This report describes CHEM2D-H2O, a new parameterization of H2O photochemical production and loss based on the CHEM2D photochemical-transport model of the middle atmosphere. This parameterization accounts for the altitude, latitude, and seasonal variations in the photochemical sources and sinks of water vapor over the pressure region from 100–0.001 hPa (~16–90 km altitude). A series of free-running NOGAPS-ALPHA forecast model simulations offers a preliminary assessment of CHEM2D-H2O performance over the June 2007 period. Results indicate that the CHEM2D-H2O parameterization improves global 10-day forecasts of upper mesospheric water vapor compared to forecasts using an existing one-dimensional (altitude only) parameterization. Most of the improvement is seen at high winter latitudes where the one-dimensional parameterization specifies photolytic H2O loss year round despite the lack of sunlight in winter. The new CHEM2D-H2O parameterization should provide a better representation of the downwelling of dry mesospheric air into the stratospheric polar vortex in operational analyses that do not assimilate middle atmospheric H2O measurements.

scholarly journals Parameterization of middle atmospheric water vapor photochemistry for high-altitude NWP and data assimilation

2008 ◽  
Vol 8 (24) ◽  
pp. 7519-7532 ◽  
Author(s):  
J. P. McCormack ◽  
K. W. Hoppel ◽  
D. E. Siskind
Keyword(s):  
Water Vapor ◽  
Middle Atmosphere ◽  
Transport Model ◽  
Polar Vortex ◽  
Forecast Model ◽  
Stratospheric Polar Vortex ◽  
One Dimensional ◽  
Sources And Sinks ◽  
Free Running ◽  
The One

Abstract. This paper describes CHEM2D-H2O, a new parameterization of H2O photochemical production and loss based on the CHEM2D photochemical-transport model of the middle atmosphere. This parameterization accounts for the altitude, latitude, and seasonal variations in the photochemical sources and sinks of water vapor over the pressure region from 100–0.001 hPa (~16–90 km altitude). A series of free-running NOGAPS-ALPHA forecast model simulations offers a preliminary assessment of CHEM2D-H2O performance over the June 2007 period. Results indicate that the CHEM2D-H2O parameterization improves global 10-day forecasts of upper mesospheric water vapor compared to forecasts using an existing one-dimensional (altitude only) parameterization. Most of the improvement is seen at high winter latitudes where the one-dimensional parameterization specifies photolytic H2O loss year round despite the lack of sunlight in winter. The new CHEM2D-H2O parameterization should provide a better representation of the downwelling of dry mesospheric air into the stratospheric polar vortex in operational analyses that do not assimilate middle atmospheric H2O measurements.

scholarly journals Six years of total ozone column measurements from SCIAMACHY nadir observations

2008 ◽  
Vol 1 (1) ◽  
pp. 249-279
Author(s):  
C. Lerot ◽  
M. Van Roozendael ◽  
J. van Geffen ◽  
J. van Gent ◽  
C. Fayt ◽  
...  
Keyword(s):  
Cross Sections ◽  
Total Ozone ◽  
Large Scale ◽  
European Space Agency ◽  
Data Sets ◽  
Data Set ◽  
Ozone Data ◽  
Space Agency ◽  
German Aerospace ◽  
The Impact

Abstract. Total O3 columns have been retrieved from six years of SCIAMACHY nadir UV radiance measurements using SDOAS, an adaptation of the GDOAS algorithm previously developed at BIRA-IASB for the GOME instrument. GDOAS and SDOAS have been implemented by the German Aerospace Center (DLR) in the version 4 of the GOME Data Processor (GDP) and in version 3 of the SCIAMACHY Ground Processor (SGP), respectively. The processors are being run at the DLR processing centre on behalf of the European Space Agency (ESA). We first focus on the description of the SDOAS algorithm with particular attention to the impact of uncertainties on the reference O3 absorption cross-sections. Second, the resulting SCIAMACHY total ozone data set is globally evaluated through large-scale comparisons with results from GOME and OMI as well as with ground-based correlative measurements. The various total ozone data sets are found to agree within 2% on average. However, a negative trend of 0.2–0.4%/year has been identified in the SCIAMACHY O3 columns; this probably originates from instrumental degradation effects that have not yet been fully characterized.

scholarly journals Measurement report: Regional trends of stratospheric ozone evaluated using the MErged GRIdded Dataset of Ozone Profiles (MEGRIDOP)

2020 ◽  
Author(s):  
Viktoria F. Sofieva ◽  
Monika Szelag ◽  
Johanna Tamminen ◽  
Erkki Kyrölä ◽  
Doug Degenstein ◽  
...  
Keyword(s):  
Stratospheric Ozone ◽  
European Space Agency ◽  
Polar Vortex ◽  
Polar Regions ◽  
High Latitudes ◽  
Longitudinal Structure ◽  
Gridded Dataset ◽  
Space Agency ◽  
Ozone Profile ◽  
Ozone Trends

Abstract. In this paper, we present the MErged GRIdded Dataset of Ozone Profiles (MEGRIDOP) in the stratosphere with a resolved longitudinal structure, which is derived from data by six limb and occultation satellite instruments: GOMOS, SCIAMACHY and MIPAS on Envisat, OSIRIS on Odin, OMPS on Suomi-NPP, and MLS on Aura. The merged dataset was generated as a contribution to the European Space Agency Climate Change Initiative Ozone project (Ozone_cci). The period of this merged time series of ozone profiles is from late 2001 until the end of 2018. The monthly mean gridded ozone profile dataset is provided in the altitude range from 10 to 50 km in bins of 10° latitude × 20° longitude. The merging is performed using deseasonalized anomalies. The created MEGRIDOP dataset can be used for analyses, which probe our understanding of stratospheric chemistry and dynamics. To illustrate some possible areas of applications, we created the climatology of ozone profiles with resolved longitudinal structure. We found zonal asymmetry/structures in the climatological ozone profiles at middle and high latitudes associated with the polar vortex. At Northern high latitudes, the amplitude of the seasonal cycle also has a longitudinal dependence. The MEGRIDOP dataset has been also used to evaluate regional vertically-resolved ozone trends in the stratosphere, including polar regions. It is found that stratospheric ozone trends exhibit longitudinal structures at Northern Hemisphere middle and high latitudes, with enhanced trends over Scandinavia and Atlantic region. This agrees well with previous analyses and might be due to changes in dynamic processed related to the Brewer-Dobson circulation.

scholarly journals Measurement report: regional trends of stratospheric ozone evaluated using the MErged GRIdded Dataset of Ozone Profiles (MEGRIDOP)

2021 ◽  
Vol 21 (9) ◽  
pp. 6707-6720
Author(s):  
Viktoria F. Sofieva ◽  
Monika Szeląg ◽  
Johanna Tamminen ◽  
Erkki Kyrölä ◽  
Doug Degenstein ◽  
...  
Keyword(s):  
Stratospheric Ozone ◽  
European Space Agency ◽  
Polar Vortex ◽  
Polar Regions ◽  
High Latitudes ◽  
Longitudinal Structure ◽  
Gridded Dataset ◽  
Space Agency ◽  
Ozone Profile ◽  
Ozone Trends

Abstract. In this paper, we present the MErged GRIdded Dataset of Ozone Profiles (MEGRIDOP) in the stratosphere with a resolved longitudinal structure, which is derived from data from six limb and occultation satellite instruments: GOMOS, SCIAMACHY and MIPAS on Envisat, OSIRIS on Odin, OMPS on Suomi-NPP, and MLS on Aura. The merged dataset was generated as a contribution to the European Space Agency Climate Change Initiative Ozone project (Ozone_cci). The period of this merged time series of ozone profiles is from late 2001 until the end of 2018. The monthly mean gridded ozone profile dataset is provided in the altitude range from 10 to 50 km in bins of 10∘ latitude × 20∘ longitude. The merging is performed using deseasonalized anomalies. The created MEGRIDOP dataset can be used for analyses that probe our understanding of stratospheric chemistry and dynamics. To illustrate some possible applications, we created a climatology of ozone profiles with resolved longitudinal structure. We found zonal asymmetry in the climatological ozone profiles at middle and high latitudes associated with the polar vortex. At northern high latitudes, the amplitude of the seasonal cycle also has a longitudinal dependence. The MEGRIDOP dataset has also been used to evaluate regional vertically resolved ozone trends in the stratosphere, including the polar regions. It is found that stratospheric ozone trends exhibit longitudinal structures at Northern Hemisphere middle and high latitudes, with enhanced trends over Scandinavia and the Atlantic region. This agrees well with previous analyses and might be due to changes in dynamical processes related to the Brewer–Dobson circulation.

Sign in / Sign up

Export Citation Format

Share Document