Total Ozone Fluctuations Research Articles

On the association of aerosol optical depth and total ozone fluctuations with recent earthquakes in Greece

A number of recent studies suggest that atmospheric changes that precede an earthquake might offer the hope of providing early warning. This study attempts to examine seismo-atmospheric anomalies around the time and the location of some of the major earthquakes in Greece in the period 2001–2015. Daily values of aerosol optical depth (AOD) and total ozone column (TOZ) obtained from satellite observations are used, in the time window between 25 days before and 14 days after each of these events, in a 1° × 1° area centred on the epicentre of each earthquake. For some of these earthquake events, abnormal increases in time series of AOD and TOZ data were detected before and after the occurrence of the earthquake. Nevertheless, in other cases, no clear anomalies were observed around the earthquake date. In addition, examining the statistics of AOD and TOZ daily values, there were many cases of prominent abnormal variations, without, however, being associated with an earthquake event. Therefore, no clear association was found between AOD and TOZ fluctuations and recent earthquakes in Greece.

On the 11 year solar cycle signature in global total ozone dynamics

AbstractThe main aim of the present study is to investigate further the association between total ozone (TOZ) and the 11 year solar cycle (SC) during the period 1979–2010, by employing satellite observations of TOZ made by Nimbus‐7, Meteor‐3, Earth Probe Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI) instrumentation. A statistically significant correlation between the annual mean TOZ over both hemispheres and sunspot number (SN) is found. On the contrary, focusing on the January and February mean monthly TOZ fluctuations from the equator to the high latitudes of the Northern Hemisphere, no association between TOZ and SN is derived. This is attributed to the existence of the quasi‐biennial‐oscillation (QBO) and the El Niño‐Southern oscillation (ENSO) in the TOZ time series. The latter oscillation is herewith expressed by the recently introduced Ozone ENSO Index (OEI). However, when considering the TOZ zonal means centred at 17.5 and 27.5°N during the east phase years of the QBO in the equatorial zonal wind at 50 hPa, a statistically significant correlation between TOZ and SN is revealed. It is an indication that the quasi‐periodic fluctuations (i.e. QBO, ENSO) strongly contaminate the relationship between TOZ and solar activity. Plausible mechanisms are discussed, exploring the momentum flux (MF) measurements between 45 and 75°N, in the periods of increased dynamical variability. The findings obtained point to the conclusion that the 11 year solar cycle response in TOZ is caused by dynamical changes which are caused by solar activity. These are of crucial importance because solar radiation is a major driving force of the climate system. Copyright © 2012 Royal Meteorological Society

Ozone anomaly statistics over Europe over a period of instrumental observation

There is no standard practice for classifying strong ozone fluctuations over middle latitudes. Normally attention is paid mainly to the short-term strong decline of total ozone (ozone mini-holes) over specific regions. Meanwhile positive total ozone fluctuations are also of significant interest. Here we report on the overall statistics of total ozone anomalies over the European continent during the whole period of observation.

Synoptic-Scale Variability and Its Relationship with Total Ozone and Antarctic Vortex Displacements

Abstract The main synoptic-scale circulation anomaly pattern over extratropical South America during the austral spring (September–November) is identified by means of rotated extended empirical orthogonal function techniques, applied to the meridional wind perturbation time series at 300 hPa. The dataset is based on 15 spring seasons (1979–93) of meteorological data from the National Centers for Environmental Prediction–Department of Energy Atmospheric Model Intercomparison Project version-2 daily averaged reanalyses, given in 17 vertical levels from 1000 to 10 hPa. The total-ozone daily measurements for the same period are from the Total Ozone Mapping Spectrometer instrument (version 7). The principal synoptic-scale anomaly pattern is associated with an anticyclone–cyclone pair evolving eastward along subpolar latitudes (and hence it is termed the subpolar mode), with a typical length scale of 5000 km and a phase velocity of 8 m s−1. The subpolar-mode waves, which display the main characteristics of midlatitude baroclinic waves, typically maximize near or above the tropopause and propagate upward into the lower stratosphere, showing large amplitudes even at 50 hPa and above. Subpolar-mode-related circulation anomalies are found to be responsible for large total-ozone daily fluctuations near southern South America and nearby regions. In the positive phase of the subpolar mode, total-ozone fluctuations, which are negative, adopt a sigmoid structure, with a zonal scale as large as the anticyclone–cyclone pair. Moreover, it is herein shown that the associated anticyclone produces a local ozone-column decrease to the north and east of its center, due to adiabatic uplift of air parcels in the upper troposphere and lower stratosphere. At the same time, the downstream cyclonic disturbance is responsible for large negative total-ozone anomalies to the west and south of its center. As the cyclone develops in the lower stratosphere, it promotes the northward incursion of the Antarctic vortex up to about 55°S, along with air masses of highly depleted ozone levels.

A model study of total ozone evolution 1979–2000 — the role of individual natural and anthropogenic effects

The SUNY‐SPB 2‐D model is used to model ozone behavior during the period 1970–2000. The roles of different natural and human‐induced impacts (solar variability, volcanoes, changes in dynamics, increasing chlorine and bromine concentrations) on the column ozone are studied separately as well as in combination. We found that variations in solar UV radiation produce global total ozone fluctuations that are comparable to those due to volcanic eruptions and increasing concentrations of chlorine and bromine during this period. We also suggest that the physical reason for the different observed time behavior of total ozone in the Northern and Southern Hemisphere middle latitudes during the 1990s may be found in the greater importance of mixing of polar processed air into middle latitudes in the Southern hemisphere.

Development of meteorological parameters and total ozone during the total solar eclipse of August 11, 1999

During the total eclipse of August 11, 1999 frequent showers occurred due to a unstable stratification of the air mass. At different observation sites, meteorological effects from the eclipse (99.4% coverage at Hohenpeissenberg) and from showers were superimposed making it partly difficult to unambiguously interpret the observations. The weather radar at Hohenpeissenberg observatory provided a general overview of the distribution of clouds and precipitation in this area (200 km diameter). From the Garching site in the zone of totality (100%) temperature and wind data taken on a 50 m mast were evaluated. By selecting periods with relatively low cloud cover it was possible to approximately follow the development of the vertical temperature and wind profiles during the eclipse. The minimum temperature at Hohenpeissenberg (about 450 m above the altitude of Garching) during the eclipse was comparable to that during the previous night, the corresponding value measured at Garching remained about 2 K above the minimum observed during clear sky conditions in the previous night. Showers before, during or after the eclipse may have induced vertical exchange of air parcels. Temperatures during a shower change towards the same direction at all altitudes, thus no inversion forms. Additionally, air parcels with relatively lower concentrations of trace constituents were transported down from aloft for time periods of 10-15 minutes. These mixing processes significantly determined the temporal variations of various trace substances measured during the eclipse. Total ozone measurements at Hohenpeissenberg were performed with both DOBSON and BREWER spectrophotometers and at another site within the zone of totality by using a portable Microtops II filter instrument. Different results were obtained for both sites. These differences can be to a large extend, but not exclusively, attributed to eclipse induced shifts (limb darkening and straylight effects in the atmosphere) in the wavelength pairs used to calculate total ozone. However, there also appeared to be real fluctuations in total ozone during the reemerging phase of the sun which may be related to eclipse induced gravity waves.

Solar UV‐B irradiance and total ozone in Italy: Fluctuations and trends

Solar UV irradiance spectra (290–325 nm) together with daily total ozone column observations have been collected since 1992 by means of Brewer spectrophotometers at two Italian stations (Rome and Ispra). The available Brewer irradiance data, recorded around noon and at fixed solar zenith angles, together with the output of a radiative transfer model (the STAR model) are presented and analyzed. The Brewer irradiance measurements and total ozone fluctuations and anomalies are investigated, pointing out the correlation between the high‐frequency O3 components and irradiance at 305 nm. In addition, the total ozone long time series of Arosa (170 km apart from Ispra) and Vigna di Valle (very close to Rome) are analyzed to illustrate evidence of temporal variations and a possible trend.

Daily variations in TOMS total ozone data

The spatial and seasonal distributions of daily fluctuations in total ozone from 60°N to 60°S are analyzed by using 14.5 years of total ozone mapping spectrometer (TOMS) data on a 5° latitude by 15° longitude grid. Root mean square day to day differences maximize near 30 Dobson units (DU) in the midlatitudes of both hemispheres from late fall to early spring. The contributions of these fluctuations due to planetary‐ and medium‐scale waves are analyzed using sinusoidal zonal wave filtering. Daily midlatitude variations from planetary‐scale waves are smaller than those from medium‐scale waves and mainly occur from late fall to early spring, while strong medium‐scale variations persist throughout fall, winter, and spring. An exception is the southern hemisphere high latitudes, where contortions and breakup of the polar vortex cause large daily variations on planetary scales during September and October. Tropical total ozone fluctuations due to planetary‐scale waves are slightly larger than those due to medium‐scale waves in all seasons. A climatological table of monthly RMS day to day total ozone changes is provided as a reference.

Dynamical Response of the Tropical Total Ozone to Sea Surface Temperature Changes

Interannual variations of total ozone in the equatorial region are discussed in terms of the lower-stratospheric dynamical processes associated with sea surface temperature (SST) changes on an El Nino-Southern Oscillation time scale. Tropospheric diabatic heating by the latent heat release in convective systems drives the interannual variations of tropopause height and atmospheric vertical motions. The adiabatic cooling associated with the dynamically forced ascending motion is subject to radiative heating, which further extends the upwelling motion into the stratosphere. SST variations can thus influence total ozone amounts by changing the tropopause height and vertical advection through modulation of tropospheric diabatic heating. Mechanistic relationships that describe total ozone fluctuations through the advection effect and the tropopause effect of SST variations are derived using the equivalent potential temperature. Total ozone fluctuations are estimated using a quantitative formulation of these mechanistic equations together with the observed SST data. These results indicate that the interannual variations of the zonal wave component of equatorial total ozone are governed by the tropopause effect of SST variations. Preliminary investigation suggests that the annual cycle of tropical total ozone is coupled to the tropopause height changes under the influence of the planetary wave-induced lower-stratospheric temperature rather than local SST.

Multi wavelength measurements of atmospheric turbidity and determination of the fluctuations in total ozone over Antarctica

Sun photometer measurements have been made at λ = 310, 368 and 500 nm during a number of Indian expeditions to Antarctica. The measurements have also been made at λ = 368 and 500 nm over the ocean on a cruise to one of the expeditions. Both the optical depth ( a H ) and the turbidity ( T ) due to atmospheric haze aerosols have been computed over the ocean and over Antarctica. In general, the values of the optical depth are higher at λ = 368 nm that at λ = 500 nm. The values of the optical depth (and turbidity) are also higher over the ocean than over Antarctica. Based on the measurements made at λ = 368 and 500 nm, the exponent α = 2 describes the wavelength dependence of the optical depth. This wavelength dependence of the optical depth has been used to obtain the optical depth at λ = 310 nm. The corresponding value of the selective absorption due to ozone ( kx ≈ 1.1, total ozone x = 0.3 atm-cm) is much greater than the aerosol optical depth a H (≈ 0.11). The optical depth due to Rayleigh scattering ( a R ≈ 1.03) being constant. The relative variability (rms/mean), due to fluctuations on time-scales of a few hours to daily variations, in the computed values of the optical depth a H has been observed to be about 6% during January 1988. The relative variability in the measured intensity at λ = 310 nm, at a zenith angle of 60°, during this period is observed to be about 14%. The relative variability in the total ozone obtained from in situ measurements with the Total Ozone Mapping Spectrometer (TOMS) for the same period is about 3%. It is shown that the wavelength λ = 310 nm, which is towards the upper limits of the u.v.-B band that is highly absorbed, is perhaps best suited to monitor fluctuations in the total ozone (x). This technique is likely to be more effective during the local spring period of September–November over Antarctica, where the phenomenon of the ozone ‘hole’ occurs.

Ozone measurements from the NOAA-9 and the Nimbus-7 satellites: implications of short and long term variabilities

This paper gives an overview of the measurements of total ozone and ozone profiles by the SBUV/2 instrument on the NOAA-9 spacecraft relative to similar measurements from the SBUV and TOMS instruments on Nimbus-7. It is shown that during the three year period from March 14, 1985 to February 28, 1988, when these data sets overlap, there have been significant changes in the calibrations of the three instruments that may be attributed to diffuser plate degradation (for SBUV/TOMS) and to the drift of the NOAA-9 orbit to later equator crossing times (for SBUV/2). These changes in instrument characteristics have affected the absolute values of the trends derived from the three instruments, but their geophysical characteristics and response to short-term variations are accurate and correlate well among the three instruments. For example, the total column ozone measured by the three instruments shows excellent agreement with respect to its day to day, seasonal, and latitudinal variabilities. At high latitudes, the day to day fluctuations in total ozone show a strong positive correlation with temperature in the lower stratosphere, as one might expect from the dynamical coupling of the two parameters at these latitudes.

Ozone measurements from the NOAA-9 and the NIMBUS-7 satellites: Implications of short and long term variabilities

This paper gives an overview of the measurements of total ozone and ozone profiles by the SBUV/2 instrument on the NOAA-9 spacecraft relative to similar measurements from the SBUV and TOMS instruments on Nimbus-7. It is shown that during the three year period from March 14, 1985, to February 28, 1988, when these data sets overlap, there have been significant changes in the calibrations of the three instruments that may be attributed to diffuser plate degradation (for SBUV/TOMS) and to the drift of the NOAA-9 orbit to later equator crossing times (for SBUV/2). These changes in instrument characteristics have affected the absolute values of the trends derived from the three instruments, but their geophysical characteristics and response to short term variations are accurate and correlate well among the three instruments. For example, the total column ozone measured by the three instruments shows excellent agreement with respect to its day to day, seasonal, and latitudinal variabilities. At high latitudes, the day to day fluctuations in total ozone show a strong positive correlation with temperature in the lower stratosphere, as one might expect from the dynamical coupling of the two parameters at these latitudes.

Recent large fluctuations in total ozone

Total ozone changes have been examined for the past 29 years at 32 stations selected from the 70 surface stations in the global ozone network. Recent changes have been dominated by negative anomalies of two general types: reductions in the antarctic since 1980 in spring and deficits since late 1982 primarily in middle latitudes and centred on winter and spring. When significant anomalies from the 1963–1979 monthly means are tabulated world-wide, it is found that positive anomalies were substantially in excess in 1970 only, whereas negative anomalies have dominated in each of the years 1983 to 1986. Springtime correlations between ozone and temperature at the south pole for the period 1963–1979 are used in linear regression models to predict ozone from temperature for the period since 1980. Recent observed ozone values are consistently lower than values predicted by these models. A potential contributor to the antarctic springtime deficits is reduced planetary wave transport of ozone from the middle latitudes into the lower polar stratosphere accompanying a change in the atmospheric general circulation pattern that is also manifested in global sea surface temperature patterns. Northern hemisphere middle latitude deficits are thought to be related to trace substances ejected by the El Chichon volcanic eruption in April 1982, although equatorward of 45°N negative anomalies are accentuated by the quasi-biennial oscillation.

Recent large fluctuations in total ozone

AbstractTotal ozone changes have been examined for the past 29 years at 32 stations selected from the 70 surface stations in the global ozone network. Recent changes have been dominated by negative anomalies of two general types: reductions in the antarctic since 1980 in spring and deficits since late 1982 primarily in middle latitudes and centred on winter and spring. When significant anomalies from the 1963–1979 monthly means are tabulated world‐wide, it is found that positive anomalies were substantially in excess in 1970 only, whereas negative anomalies have dominated in each of the years 1983 to 1986. Springtime correlations between ozone and temperature at the south pole for the period 1963–1979 are used in linear regression models to predict ozone from temperature for the period since 1980. Recent observed ozone values are consistently lower than values predicted by these models. A potential contributor to the antarctic springtime deficits is reduced planetary wave transport of ozone from the middle latitudes into the lower polar stratosphere accompanying a change in the atmospheric general circulation pattern that is also manifested in global sea surface temperature patterns. Northern hemisphere middle latitude deficits are thought to be related to trace substances ejected by the El Chichon volcanic eruption in April 1982, although equatorward of 45°N negative anomalies are accentuated by the quasi‐biennial oscillation.

Solar cycle in surface air temperature

Statistical significant determinations of the 11 y wave in historical surface air temperature series have been obtained. This weak solar-induced signal has been successfully related to total ozone fluctuations.

Ozone transport by diabatic and planetary wave circulations on a β plane

A β plane model is used to study the transport of ozone and a tracer distributed like ozone. In the first experiment, ozone is transported with a time dependent diabatic circulation in a β channel. Increase in the ozone column density occurs principally through downward advection from the high altitude source region into the lower stratosphere. Compared with observations, the maximum in the total ozone field occurs too late and is too large. Transient planetary waves produce large temporary increases in total ozone near the pole during sudden warming events, but permanent increases are much smaller. Warmings which penetrate below the chemical transition region (major warmings) are most effective in changing the zonal mean ozone distribution. Combining the sudden warming and diabatic circulations simulates many of the observed features of the seasonal changes in total ozone at high latitudes. The diabatic circulation provides the major enhancement of the ozone column density while the transient planetary waves move ozone to high latitudes. This result suggests sudden warmings can play an important role in our understanding of the fluctuations in total ozone, and the final warming may be the key event which determines the date and magnitude of the spring maximum.

Thermal response to ozone fluctuations of the stratosphere

Although the stratospheric temperature inversion is clearly due to absorption of sunlight (and terrestrial emission in the infrared), it is not established that fluctuations in ozone are responsible for fluctuations in stratospheric temperatures. A large data base of radiosonde temperatures is available, but the only comparable data for ozone are the total column densities. We find that fluctuations in total ozone and radiosonde temperatures in the lower stratosphere (50–100 mbar) show correlations of the magnitude expected for ozone control of the heating. At the higher altitudes examined in this study (10–30 mbar) the relationship between ozone and temperature is diminished, possibly because of (1) overhead changes in opacity with a change in the local ozone concentration (negative feedback), (2) dependence of the local ozone concentration on temperature (which offsets the dependence of T on [O3]), and (3) adiabatic dependences of T on density arising from the vertical components of ozone transport (which are not necessarily dependent on ozone absorption). At low altitudes, just above the tropopause in the subtropical summer, the heating of the stratosphere is due mainly to absorption of ground radiation in the 9.6‐μm O3 band and direct solar radiation in the near ultraviolet, and the confusing factors that occur at higher levels and high latitudes are diminished.

Global Analysis of Recent Total Ozone Fluctuations

Total ozone data for various regions of the world have been examined on a seasonal and annual basis. The increase in total ozone noted during the 1960's appears to have ended, and at United States and British stations there was a significant 2% reduction in ozone between 1970 and 1974, although the annual race of decrease diminished from 0.7% between 1971 and 1972 to 0.2% between 1973 and 1974. In the United States the 2% reduction returned the total ozone value nearly to its 1963 level, but in Great Britain (and at Huancayo, Peru) the decrease amounted to only one-third (one-fifth) of the increase during the 1960's. The existence of a quasi-biennial oscillation in total ozone, variable in phase, amplitude, and period, makes extremely difficult the detection of any effect on the ozone shield due to the large Russian nuclear explosions in 1961 and 1962. We fail to find an unambiguous effect, and suggest that, on a seasonal or annual basis, these nuclear tests could not have reduced the hemispheric total-ozone amount by more than 1–2%. There is no evidence of a decrease in total ozone over Japan during the passage of radioactive clouds following individual Chinese tests in 1968, 1969, and 1970. The coincidence of the breakdown of the quasi-biennial oscillation in total ozone at Aspendale and Brisbane in the exact season (spring, 1963) of the eruption of Mt. Agung (8°S) is noted. For whatever reason, it appears that the Southern Hemisphere ozone values were anomalously high (or indicated to be anomalously high) following the eruption, but the lengthening of the period of quasi-biennial oscillation during this time may also be influencing, or even dominating, the results. The sunspot-total ozone relation is reexamined using the available data. There is limited evidence of a nearly in-phase relationship; accordingly, the decrease in total ozone between 1970 and 1974 may be associated with the decrease in sunspot number following the sunspot maximum in 1969. There appears to have been some decrease in total ozone in north latitudes following intense solar flares (solar proton events) in 1960, 1966, and 1972, but the relationship is not conclusive.

Comments on “Quasi-Biennial and Long-Term Fluctuations in Total Ozone”

Comments on “Quasi-Biennial and Long-Term Fluctuations in Total Ozone”

Quasi-Biennial and Long-Term Fluctuations In Total Ozone

Abstract Quasi-biennial and long-term fluctuations in total ozone are estimated from stations with more than 4 yr of record in north polar, tropical, south temperate, and south polar latitudes and more than 8 yr of record in north temperate latitudes. The quasi-biennial total-ozone fluctuations tend to be out of phase in tropical and extratropical latitudes, with the extratropical fluctuations better organized in the Southern than Northern Hemisphere. In the Tropics, the quasi-biennial total-ozone and zonal wind oscillations are significantly in phase, but, in extratropical latitudes, the total-ozone fluctuations are alternately in phase and out of phase with the tropical zonal wind oscillation, the out-of-phase relation being the dominant one. There is the suggestion that the Mt. Agung volcanic eruption in 1963 caused a breakdown of the quasi-biennial, total-ozone oscillation in the Southern Hemisphere subtropics, with anomalously high ozone values a few months after the eruption. We derive, for the past...