scholarly journals Compilation of ozonesonde observation over Schirmacher oasis east Antarctic from 1999-2007

MAUSAM ◽  
2021 ◽  
Vol 64 (4) ◽  
pp. 613-624
Author(s):  
R.P. LAL ◽  
SURESH RAM
Keyword(s):  
Ozone Depletion ◽  
Vertical Profile ◽  
India Meteorological Department ◽  
Ozone Hole ◽  
Profile Measurement ◽  
Yearly Variation ◽  
Vertical Column ◽  
Ozone Profile ◽  
Schirmacher Oasis ◽  
The Mean

Hkkjr ekSle foKku foHkkx }kjk Hkkjrh; bysDVªks&dsfedy vkstksulkSans dh enn ls ,aVkdZfVdk ij Hkkjr ds nwljs LVs'ku eS=h ¼70-7 fMxzh n-] 11-7 fMxzh iw-½ ls vkstksu fLFkfr ¼izksQkby½ dk fu;fer eki fd;k tk jgk gSA ok;qeaMy ds mnxz LraHk esa vkstksu ds ?kuRo dh x.kuk iwjs o"kZ esa fy, x, lkIrkfgd vkstksu lkmfUMax ls dh tkrh gSA ok;qeaMyh; vkstksu dh mnxz fLFkfr ¼izksQkby vkSj vkstksu fNnz ¼gksy½ dh fo'ks"krkvksa dk v/;;u djus ds fy, flracj&vDVwcj ekg ds nkSjku cgqr ckj ifjKfIr;k¡ ¼lkmfUMax½ yh xbZ gSaA bl 'kks/k i= esa lrg ls 10 gsDVk ik- ds chp vkstksu vkSj rkieku ds ekfld ,oa okf"kZd vkSlr esa fofo/krk dh x.kuk ,oa fo'ys"k.k o"kZ 1999 ls 2007 dh vof/k esa fy, vkstksulkSans vkjksg.kksa ls fd;k x;k gSA bl v/;;u ls irk pyk gS fd vkstksu fNnz ds laca/k esa xgu vo{k; vDrwcj esa vkSj vYi ijUrq egRoiw.kZ vo{k; flracj ekg esa gqvk gSA vDrwcj esa yxHkx 250 ,oa 20 gs-ik- ds chp lcls lqLi"V vo{k; gqvk gS ftlesa vf/kdre LFkkuh; vkstksu ds Lrj esa 70 gs-ik- vkSj 10 gs- ik- ds Lrjksa ij vkSj flrEcj esa 70 gs- ik- ij fxjkoV  ns[kh xbZA fHkUu&fHkUu nkc Lrjksa ds fy, vkstksu dk rkieku ds lkFk lglaca/k ls ubZ tkudkfj;ksa vkSj vkstksu ifjorZu esa foLrkj dk irk pyk gSA iwjs o"kZ esa 300 ls 50 gs- ik- ds chp U;wure okf"kZd vkSlr rkieku -55 fMxzh ls -63 fMxzh lsaVhxzsM rd cnyrk gSA vxLr vkSj flrEcj ds eghuksa esa     70 gs- ik- rFkk 100 gs- ik- Lrjksa ij rkieku dk -80 fMxzh lsaVhxzsM ls de gksuk ,oa vDrwcj ekg esa 70 gs- ik- rFkk 100 gs- ik- Lrjksa ij yxHkx -70 fMxzh lsaVhxzsM ls de gksus dh fLFkfr dks vDrwcj ekg esa vkst+ksu vo{k; ds ladsrd ds :i esa ekuk tk ldrk gSA Regular ozone profile measurement over Antarctica has been made by India Meteorological Department over Indian second station Maitri (70.7° S, 11.7° E) with the help of Indian electro-chemical ozonesonde. Ozone density in the vertical column of the atmosphere is computed with weekly ozone soundings taken throughout the year. During the month of September- October more frequent soundings were taken to study vertical profile of atmospheric ozone and features of ozone hole. The mean monthly and yearly variation of ozone and temperature from surface to 10 hPa has been computed and analyzed from the ozonesonde ascents for the period 1999 to 2007. The study has shown profound depletion in October and lesser but substantial depletion in September, in association with the ozone hole. Depletion is most pronounced between about 250 and 20 hPa in October, with maximum local ozone losses near   70 hPa & 100 hPa levels and in September at 70 hPa. Ozone correlations with temperature for several pressure levels have revealed new insights into the causes and extent of ozone change. Lowest annual mean temperature varies from -55 to -63 °C between 300 to 50 hPa in all the year. The temperature less than -80 °C in months of August & September at 70 hPa & 100 hPa levels and about -70 °C in month of October at 70 hPa & 100 hPa levels can be attributed as an indicator of ozone depletion in months of October

scholarly journals Measurement of Ozone at Maitri, Antarctica

MAUSAM ◽  
2021 ◽  
Vol 50 (2) ◽  
pp. 203-210
Author(s):  
V. S. TIWARI
Keyword(s):  
Surface Ozone ◽  
India Meteorological Department ◽  
Ozone Hole ◽  
Profile Measurement ◽  
Temperature Changes ◽  
Stratospheric Temperature ◽  
Ozone Profile ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
Cold Core

Regular ozone profile measurement over Antarctica has been made by India Meteorological Department since 1987 at Dakshin Gangotri and later at Maitri (70.7°S, 11.7°E) since 1990 with the help of Indian electro-chemical ozone sonde. Surface ozone measurement was also started at Dakshin Gangotri since 1989 and later at Maitri. Ozone sonde data at Dakshin Gangotri and Maitri have been analysed and ozone hole structure has been studied in detail. The drastic decrease in ozone amount is clearly seen between 100 hPa to 30 hPa layer reaching near zero value. Incidently this is the layer where highest ozone concentration occurs during other months except September-October. The ozone hole has been quite severe during 1994-95 with increase in area and depth. During 1996 the Antarctic ozone hole was also similar to previous years. An interesting feature of the 1995 event was the persistence of ozone hole through November & December. Stratospheric temperature changes during 1995 also support that the cold core vortex during 1995 was very cold and persisted up to November.

Record-breaking stratospheric smoke and record-breaking ozone depletion events in the Arctic and in Antarctica in 2020! Any link between smoke occurrence and ozone depletion?

2021 ◽  
Author(s):  
Kevin Ohneiser ◽  
Albert Ansmann ◽  
Ronny Engelmann ◽  
Boris Barja ◽  
Holger Baars ◽  
...  
Keyword(s):  
Ozone Depletion ◽  
Particle Surface ◽  
Chemical Processes ◽  
Ozone Hole ◽  
The Arctic ◽  
Aerosol Layer ◽  
Raman Lidar ◽  
Smoke Particles ◽  
Heterogeneous Chemical ◽  
Ozone Profile

<p>The highlight of our multiwavelength polarization Raman lidar measurements during the 1-year MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) expedition in the Arctic Ocean ice from October 2019 to May 2020 was the detection of a persistent, 10 km deep aerosol layer in the upper troposphere and lower stratosphere (UTLS) with clear and unambiguous wild-fire smoke signatures. The smoke is supposed to originate from extraordinarily intense and long-lasting wildfires in central and eastern Siberia in July and August 2019 and may have reached the tropopause layer by the self-lifting process.</p><p>Temporally almost parallelly, record-breaking wildfires accompanied by unprecedentedly strong pyroconvection were raging in the south-eastern part of Australia in late December 2019 and early January 2020. These fires injected huge amounts of biomass-burning smoke into the stratosphere where the smoke particles became distributed over the entire southern hemispheric in the UTLS regime from 10-30 km to even 35 km height. The stratospheric smoke layer was monitored with our Raman lidar in Punta Arenas (53.2°S, 70.9°W, Chile, southern South America) for two years.</p><p>The fact that these two events in both hemispheres coincided with record-breaking ozone hole events in both hemispheres in the respective spring seasons motivated us to discuss a potential impact of the smoke particles on the strong ozone depletion. The discussion is based on the overlapping height ranges of the smoke particles, polar stratospheric clouds, and the ozone hole regions. It is well known that strong ozone reduction is linked to the development of a strong and long-lasting polar vortex, which favours increased PSC formation. In these clouds, active chlorine components are produced via heterogeneous chemical processes on the surface of the PSC particles. Finally, the chlorine species destroy ozone molecules in the spring season. However, there are two pathways to influence ozone depletion by aerosol pollution. The particles can influence the evolution of PSCs and specifically their microphysical properties (number concentration and size distribution), and on the other hand, the particles can be directly involved in heterogeneous chemical processes by increasing the particle surface area available to convert nonreactive chlorine components into reactive forms. A third (indirect) impact of smoke, when well distributed over large parts of the Northern or Southern hemispheres, is via the influence on large-scale atmospheric dynamics.</p><p>We will show our long-term smoke lidar observations in the central Arctic and in Punta Arenas as well as ozone profile measurements during the ozone-depletion seasons. Based on these aerosol and ozone profile data we will discuss the potential interaction between smoke and ozone.</p>

scholarly journals Evaluating the Performance of Ozone Products Derived from CrIS/NOAA20, AIRS/Aqua and ERA5 Reanalysis in the Polar Regions in 2020 Using Ground-Based Observations

2021 ◽  
Vol 13 (21) ◽  
pp. 4375
Author(s):  
Hongmei Wang ◽  
Yapeng Wang ◽  
Kun Cai ◽  
Songyan Zhu ◽  
Xinxin Zhang ◽  
...  
Keyword(s):  
Ozone Depletion ◽  
Ozone Hole ◽  
Detection Sensitivity ◽  
The Arctic ◽  
Polar Regions ◽  
Loss Process ◽  
Ozone Loss ◽  
Ozone Profile ◽  
The Antarctic ◽  
Polar Ozone

Quantifying spatiotemporal polar ozone changes can promote our understanding of global stratospheric ozone depletion, polar ozone-related chemical processes, and atmospheric dynamics. By means of ground-level measurements, satellite observations, and re-analyzed meteorology, the global spatial and temporal distribution characteristics of the total column ozone (TCO) and ozone profile can be quantitatively described. In this study, we evaluated the ozone datasets from CrIS/NOAA20, AIRS/Aqua, and ERA5/ECWMF for their performance in polar regions in 2020, along with the in situ observations of the Dobson, Brewer, and ozonesonde instruments, which are regarded as benchmarks. The results showed that the ERA5 reanalysis ozone field had good consistency with the ground observations (R > 0.95) and indicated whether the TCO or ozone profile was less affected by the site location. In contrast, both CrIS and AIRS could capture the ozone loss process resulting from the Antarctic/Arctic ozone hole at a monthly scale, but their ability to characterize the Arctic ozone hole was weaker than in the Antarctic. Specifically, the TCO values derived from AIRS were apparently higher in March 2020 than those of ERA5, which made it difficult to assess the area and depth of the ozone hole during this period. Moreover, the pattern of CrIS TCO was abnormal and tended to deviate from the pattern that characterized ERA5 and AIRS at the Alert site during the Arctic ozone loss process in 2020, which demonstrates that CrIS ozone products have limited applicability at this ground site. Furthermore, the validation of the ozone profile shows that AIRS and CrIS do not have good vertical representation in the polar regions and are not able to characterize the location and depth of ozone depletion. Overall, the results reveal the shortcomings of the ozone profiles derived from AIRS and CrIS observations and the reliability of the ERA5 reanalysis ozone field in polar applications. A more suitable prior method and detection sensitivity improvement on CrIS and AIRS ozone products would improve their reliability and applicability in polar regions.

scholarly journals Comparison of ozone profiles and influences from the tertiary ozone maximum in the night-to-day ratio above Switzerland

2017 ◽  
Vol 17 (17) ◽  
pp. 10259-10268 ◽  
Author(s):  
Lorena Moreira ◽  
Klemens Hocke ◽  
Niklaus Kämpfer
Keyword(s):  
Annual Variation ◽  
Lower Stratosphere ◽  
Microwave Radiometer ◽  
Relative Difference ◽  
Atmospheric Composition ◽  
Composition Change ◽  
Ozone Maximum ◽  
Ozone Profile ◽  
Mesospheric Ozone ◽  
The Mean

Abstract. Stratospheric and middle-mesospheric ozone profiles above Bern, Switzerland (46.95° N, 7.44° E; 577 m) have been continually measured by the GROMOS (GROund-based Millimeter-wave Ozone Spectrometer) microwave radiometer since 1994. GROMOS is part of the Network for the Detection of Atmospheric Composition Change (NDACC). A new version of the ozone profile retrievals has been developed with the aim of improving the altitude range of retrieval profiles. GROMOS profiles from this new retrieval version have been compared to coincident ozone profiles obtained by the satellite limb sounder Aura Microwave Limb Sounder (MLS). The study covers the stratosphere and middle mesosphere from 50 to 0.05 hPa (from 21 to 70 km) and extends over the period from July 2009 to November 2016, which results in more than 2800 coincident profiles available for the comparison. On average, GROMOS and MLS comparisons show agreement generally over 20 % in the lower stratosphere and within 2 % in the middle and upper stratosphere for both daytime and nighttime, whereas in the mesosphere the mean relative difference is below 40 % during the daytime and below 15 % during the nighttime. In addition, we have observed the annual variation in nighttime ozone in the middle mesosphere, at 0.05 hPa (70 km), characterized by the enhancement of ozone during wintertime for both ground-based and space-based measurements. This behaviour is related to the middle-mesospheric maximum in ozone (MMM).

Examining the accuracy of satellite retrievals of trace-gas emissions and lifetimes using high-resolution plume modelling.

2021 ◽  
Author(s):  
Zoe Davis ◽  
Debora Griffin ◽  
Yue Jia ◽  
Susann Tegtmeier ◽  
Mallory Loria ◽  
...  
Keyword(s):  
Wind Direction ◽  
Vertical Profile ◽  
Trace Gases ◽  
Meteorological Conditions ◽  
Point Sources ◽  
Satellite Observations ◽  
Trace Gas ◽  
Vertical Column ◽  
Retrieval Method ◽  
The Impact

<p>A recent method uses satellite measurements to estimate lifetimes and emissions of trace-gases from point sources (Fioletov et al., 2015). Emissions are retrieved by fitting measured vertical column densities (VCDs) of trace-gases to a three-dimensional function of the wind speed and spatial coordinates. In this study, a plume model generated “synthetic” satellite observations of prescribed emissions to examine the accuracy of the retrieved emissions. The Lagrangian transport and dispersion model FLEXPART (v10.0) modelled the plume from a point source over a multi-day simulation period at a resolution much higher than current satellite observations. The study aims to determine how various assumptions in the retrieval method and local meteorological conditions affect the accuracy and precision of emissions. These assumptions include that the use of a vertical mean of the wind profile is representative of the transport of the plume’s vertical column. In the retrieval method, the VCDs’ pixel locations are rotated around the source based on wind direction so that all plumes have a common wind direction. Retrievals using a vertical mean wind for rotation will be compared to retrievals using VCDs determined by rotating each altitude of the vertical profile of trace-gas using the respective wind-direction. The impact of local meteorological factors on the two approaches will be presented, including atmospheric mixing, vertical wind shear, and boundary layer height. The study aims to suggest which altitude(s) of the vertical profile of winds results in the most accurate retrievals given the local meteorological conditions. The study will also examine the impact on retrieval accuracy due to satellite resolution, trace-gas lifetime, plume source altitude, number of overpasses, and random and systematic errors. Sensitivity studies repeated using a second, “line-density”, retrieval method will also be presented (Adams et al., 2019; Goldberg et al., 2019).</p>

scholarly journals The importance of interactive chemistry for stratosphere–troposphere coupling

2019 ◽  
Vol 19 (5) ◽  
pp. 3417-3432 ◽  
Author(s):  
Sabine Haase ◽  
Katja Matthes
Keyword(s):  
Ozone Depletion ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Ocean Model ◽  
Recent Past ◽  
Stratospheric Polar Vortex ◽  
Model Version ◽  
Surface Climate ◽  
The Mean ◽  
Mean State

Abstract. Recent observational and modeling studies suggest that stratospheric ozone depletion not only influences the surface climate in the Southern Hemisphere (SH), but also impacts Northern Hemisphere (NH) spring, which implies a strong interaction between dynamics and chemistry. Here, we systematically analyze the importance of interactive chemistry with respect to the representation of stratosphere–troposphere coupling and in particular the effects on NH surface climate during the recent past. We use the interactive and specified chemistry version of NCAR's Whole Atmosphere Community Climate Model coupled to an ocean model to investigate differences in the mean state of the NH stratosphere as well as in stratospheric extreme events, namely sudden stratospheric warmings (SSWs), and their surface impacts. To be able to focus on differences that arise from two-way interactions between chemistry and dynamics in the model, the specified chemistry model version uses a time-evolving, model-consistent ozone field generated by the interactive chemistry model version. We also test the effects of zonally symmetric versus asymmetric prescribed ozone, evaluating the importance of ozone waves in the representation of stratospheric mean state and variability. The interactive chemistry simulation is characterized by a significantly stronger and colder polar night jet (PNJ) during spring when ozone depletion becomes important. We identify a negative feedback between lower stratospheric ozone and atmospheric dynamics during the breakdown of the stratospheric polar vortex in the NH, which contributes to the different characteristics of the PNJ between the simulations. Not only the mean state, but also stratospheric variability is better represented in the interactive chemistry simulation, which shows a more realistic distribution of SSWs as well as a more persistent surface impact afterwards compared with the simulation where the feedback between chemistry and dynamics is switched off. We hypothesize that this is also related to the feedback between ozone and dynamics via the intrusion of ozone-rich air into polar latitudes during SSWs. The results from the zonally asymmetric ozone simulation are closer to the interactive chemistry simulations, implying that under a model-consistent ozone forcing, a three-dimensional (3-D) representation of the prescribed ozone field is desirable. This suggests that a 3-D ozone forcing, as recommended for the upcoming CMIP6 simulations, has the potential to improve the representation of stratospheric dynamics and chemistry. Our findings underline the importance of the representation of interactive chemistry and its feedback on the stratospheric mean state and variability not only in the SH but also in the NH during the recent past.

Some Aspects of the Ecology of Lake Macquarie, N.S.W., with Regard to an Alleged Depletion of Fish. V. Chlorophyll Distribution

1959 ◽  
Vol 10 (3) ◽  
pp. 316
Author(s):  
PS Davis
Keyword(s):  
Surface Waters ◽  
Vertical Profile ◽  
Chlorophyll Concentration ◽  
Euphotic Zone ◽  
Early Summer ◽  
Late Winter ◽  
Light Penetration ◽  
Chlorophyll Distribution ◽  
The Mean ◽  
Made In

The chlorophyll a in samples from five stations in Lake Macquarie was determined over the period July 1955 to November 1956. The mean surface value for the four stations within the lake proper was 1.26 mg/m³. The vertical profile at one station was studied and the mean of these profile values was 1.23 mg/m³. Throughout the period of the survey chlorophyll concentrations in the lake varied from 0.1 to 4.0 mg/m³. The lowest values were found in the late winter and early summer (November) and the peaks during spring and autumn. The chlorophyll concentration in the surface waters of Lake Macquarie was shown to be significantly higher than that of the marine water entering the lake, but lower than that of a comparison station in the Hawkesbury River. One series of light penetration measurements made in December 1956 showed that all the water in the lake, and all but one section of Dora Creek, lay within the euphotic zone.

Components of biological variation in prolyl endopeptidase and dipeptidyl-peptidase IV activity in plasma of healthy subjects

1994 ◽  
Vol 40 (9) ◽  
pp. 1686-1691 ◽  
Author(s):  
M Maes ◽  
S Scharpé ◽  
I De Meester ◽  
P Goossens ◽  
A Wauters ◽  
...  
Keyword(s):  
Seasonal Pattern ◽  
Dipeptidyl Peptidase ◽  
Biological Variation ◽  
Dipeptidyl Peptidase Iv ◽  
Prolyl Endopeptidase ◽  
The Other ◽  
Yearly Variation ◽  
Dpp Iv ◽  
The Mean

Abstract We investigated the components of biological variation in plasma prolyl endopeptidase (PEP; EC 3.4.21.26) and dipeptidyl-peptidase IV (DPP IV; EC 3.4..14.5) activity in healthy individuals. We took monthly blood samples from 26 healthy volunteers for determination of plasma PEP and DPP IV activity during one calendar year. The estimated CVs for PEP activity were: total (CVt) = 25.0%, interindividual (CVg) = 13.9%, and intraindividual (CVi) = 16.8%. There was a statistically significant (P < 0.0001) seasonal pattern in plasma PEP activity, with significantly higher values in the fall than in the other seasons. The peak-trough difference in the yearly variation in PEP activity, expressed as a percentage of the mean, was as high as 56.8%. The estimated CVs for DPP IV activity were: CVt = 17.1%, CVg = 14.5%, and CVi = 8.2%. DPP IV activity was significantly (P < 0.0001) higher in summer than in the other seasons but the amplitude of the yearly variation was small.

scholarly journals Assessing the role of planetary and gravity waves in the vertical structure of ozone over midlatitudinal Europe

2019 ◽  
Vol 37 (4) ◽  
pp. 525-533
Author(s):  
Peter Križan
Keyword(s):  
Gravity Waves ◽  
Vertical Profile ◽  
Annual Variation ◽  
Vertical Structure ◽  
Planetary Waves ◽  
Ozone Content ◽  
Ozone Profile ◽  
Vertical Ozone Profile ◽  
Vertical Ozone

Abstract. Planetary and gravity waves play an important role in the dynamics of the atmosphere. They are present in the atmospheric distribution of temperature, wind, and ozone content. These waves are detectable also in the vertical profile of ozone and they cause its undulation. One of the structures occurring in the vertical ozone profile is laminae, which are narrow layers of enhanced or depleted ozone concentrations in the vertical ozone profile. They are connected with the total amount of ozone in the atmosphere and with the activity of the planetary and gravity waves. The aim of this paper is to quantify these processes in midlatitudinal Europe. We compare the occurrence of laminae induced by planetary waves (PL) with the occurrence of these induced by gravity waves (GL). We show that the PL are 10–20 times more frequent than that of GL. There is a strong annual variation of PL, while GL exhibit only a very weak variation. With the increasing lamina size the share of GL decreases and the share of PL increases. The vertical profile of lamina occurrence is different for PL and GL smaller than 2 mPa. For laminae greater than 2 mPa this difference is smaller.

scholarly journals Serum Apoprotein (ApoA1 and ApoB) in Myocardial infarction

1970 ◽  
Vol 26 (2) ◽  
pp. 62-66
Author(s):  
Khadija Akther Jhuma ◽  
MM Hoque
Keyword(s):  
Myocardial Infarction ◽  
Lipid Profile ◽  
Case Control Study ◽  
Profile Measurement ◽  
Specific Marker ◽  
Matched Healthy Control ◽  
Key Word ◽  
Healthy Control ◽  
The Mean ◽  
Control Study

30 diagnosed cases (Male26, Female 4) of MI (myocardial infarction) with the mean age of 55.5±9.8 years (range 40- 70 years) were included in a case control study to evaluate their apoprotein status. Serum apoA1 and apoB were measured and compared with those of age and sex matched healthy control subjects. Mean serum apoA1 concentration found significantly low in MI cases (91.84± 11.2 mg/dl) compared to control ( 123.2±10.5 mg/dl) and that of apoB found significantly high in MI cases( 135.3± 23.0 mg/dl ) compared to control (66.2±10.0 mg/dl).Serum apoB/apoA1 ratio of MI cases (1.49±0.3) also found significantly higher than that of control (0.54±0.1) .Since the serum apoA1 and apoB concentration stand for relatively more comprehensive measure of antiatherogenic and atherogenic potential respectively rather than the traditional lipid profile ; measurement of this apoprotein and their ratio may be more robust and specific marker for identification of individuals at risk of MI even in individuals with normal traditional lipid profile. Key word: ApoA1, ApoB, MI DOI: 10.3329/jbcps.v26i2.4181 J Bangladesh Coll Phys Surg 2008; 26: 62-66

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