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Papers on tropopause height

Posted by Ari Jokimäki on May 7, 2013

This is a list of papers on tropopause height. The list is not complete, and will most likely be updated in future in order to make it more thorough and more representative.

UPDATE (May 12, 2013): Lakkis et al. (2009) added.

The determination of extratropical tropopause height in an idealized gray-radiation model – Zurita-Gotor & Vallis (2013) “This paper investigates the mechanisms that determine the extratropical tropopause height, extending previous results with a Newtonian cooling model. A primitive equation model forced by a meridional gradient of incoming solar radiation, with the outgoing infra-red radiation calculated using a simple gray radiation scheme, is now used. The tropopause is defined as the top of the boundary layer over which dynamical heat transport moves the temperature away from radiative equilibrium, and its height estimated from the isentropic mass flux. Depending on parameters, this tropopause may or may not be associated with a sharp stratification change, and it may or may not be possible to define a thermal tropopause. The mass flux and thermal tropopause display similar sensitivity to external parameters when the latter can be defined, a sensitivity in good agreement with predictions by a radiative constraint. In some contrast to the Newtonian model, the radiative constraint is now quite effective in preventing adjustment to marginal criticality with realistic parameters. The meridional structure of the thermal tropopause displays a jump in height at the jet latitude, which appears to be due to the formation of a mixing barrier at the jet maximum when baroclinicity has a finite vertical scale. As meridional potential vorticity mixing is inhibited across the jet, a discontinuity is created between weakly stratified air on its warm side and strongly stratified air on its cool side. The meridional stratification contrast is created by adiabatic cooling and warming by the residual circulation, as this circulation must be deflected vertically to avoid the mixing barrier at the jet maximum.” Pablo Zurita-Gotor, Geoffrey K. Vallis, Journal of the Atmospheric Sciences 2013, doi:

A numerical simulation of aerosols’ direct effects on tropopause height – Wu et al. (2013) “The direct effects of sulfate aerosol, dust aerosol, carbonaceous aerosol, and total combined aerosols on the tropopause height are simulated with the Community Atmospheric Model version 3.1 (CAM3.1). A decrease of global mean tropopause height induced by sulfate, carbonaceous aerosol, and total combined aerosols is found, and a tropopause height increase is induced by dust aerosol. Sulfate aerosol decreases the tropospheric temperature and increases the stratospheric temperature. These effects cause a decrease in the height of the tropopause. In contrast, carbonaceous and total combined aerosols increase both the tropospheric and the stratospheric temperatures, and they also cause a decrease in the height of the tropopause. The changes in the tropopause height show highly statistically significant correlations with the changes in the tropospheric and stratospheric temperatures. The changes in the tropospheric and stratospheric temperatures are related to the changes in the radiative heat rate, cloud cover, and latent heat, but none of these factors absolutely dominate the temperature change.” Jian Wu, Yanyan Xu, Qian Yang, Zhiwei Han, Deming Zhao, Jianping Tang, Theoretical and Applied Climatology, May 2013, Volume 112, Issue 3-4, pp 659-671, DOI: 10.1007/s00704-012-0760-5.

A global blended tropopause based on ERA data. Part II: Trends and tropical broadening – Wilcox et al. (2012) “A new tropopause definition involving a flow-dependent blending of the traditional thermal tropopause with one based on potential vorticity has been developed and applied to the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalyses (ERA), ERA-40 and ERA-Interim. Global and regional trends in tropopause characteristics for annual and solsticial seasonal means are presented here, with emphasis on significant results for the newer ERA-Interim data for 1989–2007. The global-mean tropopause is rising at a rate of 47 m per decade, with pressure falling at 1.0 hPa per decade and temperature falling at 0.18 K per decade. The Antarctic tropopause shows decreasing heights, warming and increasing westerly winds. The Arctic tropopause also shows a warming, but with decreasing westerly winds. In the Tropics the trends are small, but at the latitudes of the subtropical jets they are almost double the global values. It is found that these changes are mainly concentrated in the eastern hemisphere. Previous and new metrics for the rate of broadening of the Tropics, based on both height and wind, give trends in the range 0.9–2.2° per decade. For ERA-40 the global height and pressure trends for the period 1979–2001 are similar: 39 m per decade and −0.8 hPa per decade. These values are smaller than those found from the thermal tropopause definition with this dataset, as was used in most previous studies.” L. J. Wilcox, B. J. Hoskins, K. P. Shine, Quarterly Journal of the Royal Meteorological Society, Volume 138, Issue 664, pages 576–584, April 2012 Part A, DOI: 10.1002/qj.910. [Full text]

A global blended tropopause based on ERA data. Part I: Climatology – Wilcox et al. (2012) “A new tropopause definition, based on a flow-dependent blending of the traditional thermal tropopause with one based on potential vorticity, has been developed. The benefits of such a blending algorithm are most apparent in regions with synoptic-scale fluctuations between tropical and extratropical air masses. The properties of the local air mass determine the relative contributions to the location of the blended tropopause, rather than this being determined by a specified function of latitude. Global climatologies of tropopause height, temperature, potential temperature and zonal wind, based on European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (ERA) ERA-Interim data, are presented for the period 1989–2007. Features of the seasonal-mean tropopause are discussed on a global scale, alongside a focus on selected monthly climatologies for the two high-latitude regions and the tropical belt. The height differences between climatologies based on ERA-Interim and ERA-40 data are also presented. Key spatial and temporal features seen in earlier climatologies, based mainly on the World Meteorological Organization thermal tropopause definition, are reproduced with the new definition. Tropopause temperatures are consistent with those from earlier climatologies, despite some differences in height in the extratropics.” L. J. Wilcox, B. J. Hoskins, K. P. Shine, Quarterly Journal of the Royal Meteorological Society, Volume 138, Issue 664, pages 561–575, April 2012 Part A, DOI: 10.1002/qj.951.

Monitoring Cirrus Cloud and Tropopause Height over Hanoi Using a Compact Lidar System – Hai et al. (2012) “Cirrus clouds in the upper troposphere and the lower stratosphere have attracted great attention due to their important role and impact on the atmospheric radioactive balance. Because cirrus clouds are located high in the atmosphere, their study requires a high resolution remote sensing technique not only for detection but also for the characterization of their properties. The lidar technique with its inherent high sensitivity and resolution has become an indispensible tool for studying and improving our understanding of cirrus cloud. Using lidar technique we can simultaneously measure the cloud height, thickness and follow its temporal evolution. In this paper we describe the development of a compact and highly sensitive lidar system with the aim to remotely monitor for the first time the cirrus clouds over Hanoi (21001’42’’N, 105051’12’’W). From the lidar data collected during the year 2011. We derive the mean cloud height, location of cloud top, the cloud mean thickness and their temporal evolution. We then compare the location of the cloud top with the position of the tropopause determined the radiosonde data and found good that the distance between cloud top and tropopause remains fairly stable, indicating that generally the top of cirrus clouds is the good tracer of the tropopause. We found that the cirrus clouds are generally located at height between 11.2 to 15 km with average height of 13.4 km. Their thickness is between 0.3 and 3.8 km with average value of 1.7 km. We also compare the properties of cirrus cloud with that observed at other locations around the world based on lidar technique.” Bui Van Hai, Dinh Van Trung, Nguyen Xuan Tuan, Dao Duy Thang, Nguyen Thanh Binh, Communications in Physics, Vol 22, No 4 (2012).

Dynamics of Midlatitude Tropopause Height in an Idealized Model – Zurita-Gotor & Vallis (2011) “This paper investigates the factors that determine the equilibrium state, and in particular the height and structure of the tropopause, in an idealized primitive equation model forced by Newtonian cooling in which the eddies can determine their own depth. Previous work has suggested that the midlatitude tropopause height may be understood as the intersection between a radiative and a dynamical constraint. The dynamical constraint relates to the lateral transfer of energy, which in midlatitudes is largely effected by baroclinic eddies, and its representation in terms of mean-flow properties. Various theories have been proposed and investigated for the representation of the eddy transport in terms of the mean flow, including a number of diffusive closures and the notion that the flow evolves to a state marginally supercritical to baroclinic instability. The radiative constraint expresses conservation of energy and so must be satisfied, although it need not necessarily be useful in providing a tight constraint on tropopause height. This paper explores whether and how the marginal criticality and radiative constraints work together to produce an equilibrated flow and a tropopause that is internal to the fluid. The paper investigates whether these two constraints are consistent with simulated variations in the tropopause height and in the mean state when the external parameters of an idealized primitive equation model are changed. It is found that when the vertical redistribution of heat is important, the radiative constraint tightly constrains the tropopause height and prevents an adjustment to marginal criticality. In contrast, when the stratification adjustment is small, the radiative constraint is only loosely satisfied and there is a tendency for the flow to adjust to marginal criticality. In those cases an alternative dynamical constraint would be needed in order to close the problem and determine the eddy transport and tropopause height in terms of forcing and mean flow.” Zurita-Gotor, Pablo, Geoffrey K. Vallis, 2011: Dynamics of Midlatitude Tropopause Height in an Idealized Model. J. Atmos. Sci., 68, 823–838. doi: [Full text]

Recent widening of the tropical belt from global tropopause statistics: Sensitivities – Birner et al. (2010) “Several recent studies have shown evidence for a widening of the tropical belt over the past few decades. One line of evidence uses statistics of the tropopause height to distinguish between tropics and extratropics and defines tropical edge latitudes as those latitudes at which the number of days per year with tropopause heights greater than 15 km exceeds a certain threshold (typically 200 days/yr). This definition involves two somewhat arbitrary thresholds. Here the sensitivity of the resulting widening trend of the tropical belt to these thresholds is investigated using four different reanalysis data sets. Widening trends are found to be particularly sensitive to changes in the tropopause height threshold. Ways to objectively determine appropriate thresholds to define tropical edge latitudes based on tropopause statistics are presented. Trend estimates for the width of the tropical belt from different reanalysis data sets are found to be mostly inconsistent with each other despite consistent seasonal and interannual variations.” Thomas Birner, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 115, Issue D23, 16 December 2010, DOI: 10.1029/2010JD014664. [Full text]

The Impact of Stratospheric Ozone Recovery on Tropopause Height Trends – Son et al. (2009) “The evolution of the tropopause in the past, present, and future climate is examined by analyzing a set of long-term integrations with stratosphere-resolving chemistry climate models (CCMs). These CCMs have high vertical resolution near the tropopause, a model top located in the mesosphere or above, and, most important, fully interactive stratospheric chemistry. Using such CCM integrations, it is found that the tropopause pressure (height) will continue to decrease (increase) in the future, but with a trend weaker than that in the recent past. The reduction in the future tropopause trend is shown to be directly associated with stratospheric ozone recovery. A significant ozone recovery occurs in the Southern Hemisphere lower stratosphere of the CCMs, and this leads to a relative warming there that reduces the tropopause trend in the twenty-first century. The future tropopause trends predicted by the CCMs are considerably smaller than those predicted by the Intergovernmental Panel on Climate Change Fourth Assessment Report (AR4) models, especially in the southern high latitudes. This difference persists even when the CCMs are compared with the subset of the AR4 model integrations for which stratospheric ozone recovery was prescribed. These results suggest that a realistic representation of the stratospheric processes might be important for a reliable estimate of tropopause trends. The implications of these finding for the Southern Hemisphere climate change are also discussed.” Son, Seok-Woo, and Coauthors, 2009: The Impact of Stratospheric Ozone Recovery on Tropopause Height Trends. J. Climate, 22, 429–445. doi: [Full text]

Monitoring cirrus clouds with lidar in the Southern Hemisphere: A local study over Buenos Aires. 1. Tropopause heights – Lakkis et al. (2009) “Cirrus clouds in the upper troposphere and the lower stratosphere have recently drawn much attention due to their important role and impact on the atmospheric radiative balance. Because they are located in the upper troposphere their study requires a high resolution technique not only to detect them but also to characterize their behaviour and evolution. A good dynamic range in lidar backscattering signals is necessary to observe and improve our knowledge of cirrus clouds, and thereof, atmospheric parameters in the troposphere and UT/LS due to their vicinity to the tropopause layer. The lidar system measures, in real time, the evolution of the atmospheric boundary layer, stratospheric aerosols, tropopause height and cirrus clouds evolution. The aim of the work is to present the main properties of cirrus clouds over central Argentina and to monitor tropopause height together with their temporal evolution using a backscatter lidar system located in Buenos Aires (34.6 °S, 58.5 °W). A cirrus clouds detection method was used to analyze a set of 60 diurnal events, during 2001–2005, in order to estimate tropopause height and its temporal evolution, using the top of cirrus clouds present on the upper troposphere as a tropopause tracer. The results derived from lidar show a remarkable good agreement when compared with rawinsonde data, considering values of tropopause height with differences less than or equal to 500 m, depending on the signal to noise ratio of the measurements. Clouds properties analysis reveals the presence of thick cirrus clouds with thickness between 0.5 and 4.2 km, with the top cloud located at the tropopause height.” Susan Gabriela Lakkis, Mario Lavorato, Pablo Osvaldo Canziani, Atmospheric Research, Volume 92, Issue 1, March 2009, Pages 18–26, [Full text]

Tropopause height and zonal wind response to global warming in the IPCC scenario integrations – Lorenz & DeWeaver (2007) “The change in the extratropical circulation under global warming is studied using the climate models participating in the Intergovernmental Panel on Climate Change (IPCC) fourth assessment report. The IPCC models predict a strengthening and a poleward shift of the tropospheric zonal jets in response to global warming. The change in zonal jets is also accompanied by a strengthening and a poleward and upward shift of transient kinetic energy and momentum flux. Similar changes in circulation are simulated by a simple dry general circulation model (GCM) when the height of the tropopause is raised. The similarity between the simple GCM and the IPCC models suggests that the changes in midlatitude circulation are predominantly driven by a rise in the height of the tropopause, and that other factors such as increased moisture content and the change in the low-level pole-to-equator temperature gradient, play a secondary role. In addition, the variability about the ensemble-mean of the zonal wind response is significantly correlated with the variability of the tropopause height response over the polar cap, especially in the Southern Hemisphere.” David J. Lorenz, Eric T. DeWeaver, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 112, Issue D10, 27 May 2007, DOI: 10.1029/2006JD008087. [Full text]

Contributions of Anthropogenic and Natural Forcing to Recent Tropopause Height Changes – Santer et al. (2003) “Observations indicate that the height of the tropopause—the boundary between the stratosphere and troposphere—has increased by several hundred meters since 1979. Comparable increases are evident in climate model experiments. The latter show that human-induced changes in ozone and well-mixed greenhouse gases account for ∼80% of the simulated rise in tropopause height over 1979–1999. Their primary contributions are through cooling of the stratosphere (caused by ozone) and warming of the troposphere (caused by well-mixed greenhouse gases). A model-predicted fingerprint of tropopause height changes is statistically detectable in two different observational (“reanalysis”) data sets. This positive detection result allows us to attribute overall tropopause height changes to a combination of anthropogenic and natural external forcings, with the anthropogenic component predominating.” B. D. Santer, M. F. Wehner, T. M. L. Wigley, R. Sausen, G. A. Meehl, K. E. Taylor, C. Ammann, J. Arblaster, W. M. Washington, J. S. Boyle, W. Brüggemann, Science 25 July 2003: Vol. 301 no. 5632 pp. 479-483, DOI: 10.1126/science.1084123. [Full text]

Use of changes in tropopause height to detect human influences on climate – Sausen & Santer (2003) “The height of the global-mean tropopause shows a steady increase since 1979 in re-analyses of numerical weather forecasts. This is in agreement with results from a climate model driven by natural and anthropogenic forcings. Superimposed on the multi-decadal overall trends in both simulations and re-analyses are higher-frequency fluctuations (with periods of few years) related to explosive volcanic eruptions. Global-mean tropopause height has the desirable property of acting as a natural filter, removing much of the ENSO variability that hampers the interpretation of tropospheric and surface temperature changes. In model simulations with anthropogenic forcings, changes in tropopause height can be detected roughly 20 years earlier than changes in surface temperature.” Sausen, Robert; Santer, Benjamin D., Meteorologische Zeitschrift, Volume 12, Number 3, 1 June 2003 , pp. 131-136(6), DOI:

Determining the tropopause height from gridded data – Reichler et al. (2003) “A method is presented to determine tropopause height from gridded temperature data with coarse vertical resolution. The algorithm uses a thermal definition of the tropopause, which is based on the concept of a “threshold lapse-rate”. Interpolation is performed to identify the pressure at which this threshold is reached and maintained for a prescribed vertical distance. The method is verified by comparing the heights calculated from analyses of the European Centre for Medium-Range Weather Forecasts (ECMWF) with the observed heights at individual radiosonde stations. RMS errors in the calculated tropopause heights are generally small. They range from 30–40 hPa in the extratropics to 10–20 hPa in the tropics. The largest deviations occur in the subtropics, where the tropopause has strong meridional gradients that are not adequately resolved by the input data.” Thomas Reichler, Martin Dameris, Robert Sausen, Geophysical Research Letters, Volume 30, Issue 20, October 2003, DOI: 10.1029/2003GL018240. [Full text]

Behavior of tropopause height and atmospheric temperature in models, reanalyses, and observations: Decadal changes – Santer et al. (2003) “We examine changes in tropopause height, a variable that has hitherto been neglected in climate change detection and attribution studies. The pressure of the lapse rate tropopause, pLRT, is diagnosed from reanalyses and from integrations performed with coupled and uncoupled climate models. In the National Centers for Environmental Prediction (NCEP) reanalysis, global-mean pLRT decreases by 2.16 hPa/decade over 1979–2000, indicating an increase in the height of the tropopause. The shorter European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis has a global-mean pLRT trend of −1.13 hPa/decade over 1979–1993. Simulated pLRT trends over the past several decades are consistent with reanalysis results. Superimposed on the overall increase in tropopause height in models and reanalyses are pronounced height decreases following the eruptions of El Chichón and Pinatubo. Interpreting these pLRT results requires knowledge of both T(z), the initial atmospheric temperature profile, and ΔT(z), the change in this profile in response to external forcing. T(z) has a strong latitudinal dependence, as does ΔT(z) for forcing by well-mixed greenhouse gases and stratospheric ozone depletion. These dependencies help explain why overall tropopause height increases in reanalyses and observations are amplified toward the poles. The pronounced increases in tropopause height in the climate change integrations considered here indicate that even AGCMs with coarse vertical resolution can resolve relatively small externally forced changes in tropopause height. The simulated decadal-scale changes in pLRT are primarily thermally driven and are an integrated measure of the anthropogenically forced warming of the troposphere and cooling of the stratosphere. Our algorithm for estimating pLRT (based on a thermal definition of tropopause height) is sufficiently sensitive to resolve these large-scale changes in atmospheric thermal structure. Our results indicate that the simulated increase in tropopause height over 1979–1997 is a robust, zero-order response of the climate system to forcing by well-mixed greenhouse gases and stratospheric ozone depletion. At the global-mean level, we find agreement between the simulated decadal-scale pLRT changes and those estimated from reanalyses. While the agreement between simulated pLRT changes and those in NCEP is partly fortuitous (due to excessive stratospheric cooling in NCEP), it is also driven by real pattern similarities. Our work illustrates that changes in tropopause height may be a useful “fingerprint” of human effects on climate and are deserving of further attention.” B. D. Santer, R. Sausen, T. M. L. Wigley, J. S. Boyle, K. AchutaRao, C. Doutriaux, J. E. Hansen, G. A. Meehl, E. Roeckner, R. Ruedy, G. Schmidt, K. E. Taylor, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 108, Issue D1, pages ACL 1-1–ACL 1-22, 16 January 2003, DOI: 10.1029/2002JD002258.

Interannual variability of the tropical tropopause derived from radiosonde data and NCEP reanalyses – Randel et al. (2003) “Interannual variability of the tropical tropopause is studied using long time series of radiosonde data, together with global tropopause analyses from the National Centers for Environmental Prediction (NCEP) reanalyses over 1957–1997. Comparisons for the period 1979–1997 show the NCEP tropopause temperature is too warm by ∼3–5 K and too high in pressure by ∼2–6 mbar. However, these biases are approximately constant in time, so that seasonal and interannual variability is reasonably well captured by the NCEP data. Systematic differences in NCEP tropopause statistics are observed between the presatellite (1957–1978) and postsatellite (1979–1997) periods, precluding the use of the reanalyses for the study of multidecadal variability. Interannual anomalies in tropical average radiosonde and NCEP data show variations of order ±1–2 K over the period 1979–1997, but there can be differences between these two estimates which are of similar magnitude. These differences impact estimates of decadal trends: During 1979–1997, negative trends in tropopause temperature of order −0.5 K/decade are observed in radiosonde data but are not found in NCEP reanalyses. The space-time patterns of several coherent signals are identified in both sets of tropopause statistics. The volcanic eruption of El Chichón (1982) warmed the tropical tropopause by ∼1–2 K and lowered its altitude by ∼200 m for approximately 1–2 years. Smaller tropopause variations are observed following Mount Pinatubo (1991), particularly in radiosonde data. The signatures of the quasi-biennial oscillation (QBO) and El-Nino/Southern Oscillation (ENSO) events are strong in tropopause statistics. QBO variations are primarily zonal mean in character, while ENSO events exhibit dipole patterns over Indonesia and the central Pacific Ocean, with small signals for zonal averages.” William J. Randel, Fei Wu, Dian J. Gaffen, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 105, Issue D12, pages 15509–15523, 27 June 2000, DOI: 10.1029/2000JD900155. [Full text]

Climatological characteristics of the tropical tropopause as revealed by radiosondes – Seidel et al. (2001) “A temporally and spatially comprehensive depiction of the tropical tropopause is presented, based on radiosonde data from 83 stations. Climatological statistics for 1961–1990 are computed for three levels: the conventional lapse-rate tropopause (LRT), the cold-point tropopause (CPT), and the 100 hPa level. Mean values and seasonal and interannual variations of temperature, pressure, height, potential temperature, and water vapor saturation mixing ratio at these levels are compared. The tropopause is higher, colder, and at lower pressure in the Northern Hemisphere (NH) than in the Southern Hemisphere (SH) in NH winter. This pattern reverses in NH summer, except that the tropopause remains colder in the NH than in the SH. The climatological locations of minimum tropopause temperature differ from those of maximum height and minimum pressure: In NH winter the tropopause is coldest over the western tropical Pacific warm pool region, but it is highest and at lowest pressure over the western Atlantic. Correlations of interannual anomalies in zonal-mean characteristics reveal that the height of the tropopause reflects the temperature of the underlying troposphere. Tropopause temperature, on the other hand, shows little association with tropospheric characteristics but is significantly correlated with the temperature and pressure of the lower stratosphere. The 100 hPa level is a poor surrogate for the tropical tropopause. Changes in radiosonde instrumentation limit the potential for detecting tropopause trends. However, the following (nonmonotonic) trends in the tropopause in the deep tropics during 1978–1997 seem robust: an increase in height of about 20 m decade−1, a decrease in pressure of about 0.5 hPa decade−1, a cooling of about 0.5 K decade−1, little change in potential temperature, and a decrease in saturation volume mixing ratio of about 0.3 ppmv decade−1.” Dian J. Seidel, Rebecca J. Ross, James K. Angell, George C. Reid, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 106, Issue D8, pages 7857–7878, 27 April 2001, DOI: 10.1029/2000JD900837. [Full text]

Stratospheric Influence on Tropopause Height: The Radiative Constraint – Thuburn & Craig (2000) “Earlier theoretical and modeling work introduced the concept of a radiative constraint relating tropopause height to tropospheric lapse rate and other factors such as surface temperature. Here a minimal quantitative model for the radiative constraint is presented and used to illustrate the essential physics underlying the radiative constraint, which involves the approximate balance between absorption and emission of thermal infrared (IR) radiation determining tropopause temperature. The results of the minimal model are then extended in two ways. First, the effects of including a more realistic treatment of IR radiation are quantified. Second, the radiative constraint model is extended to take into account non-IR warming processes such as solar heating and dynamical warming near the tropopause. The sensitivity of tropopause height to non-IR warming is estimated to be a few kilometers per K day−1, with positive warming leading to a lower tropopause. Sensitivities comparable to this are found in GCM experiments in which imposed changes in the ozone distribution or in the driving of the stratospheric residual mean meridional circulation lead to changes in tropopause height. In the Tropics the influence of the stratospheric circulation is found to extend down at least as far as the main convective outflow level, some 5 km below the temperature minimum.” Thuburn, John, George C. Craig, 2000: Stratospheric Influence on Tropopause Height: The Radiative Constraint. J. Atmos. Sci., 57, 17–28. doi:;2. [Full text]

Correlations between tropopause height and total ozone: Implications for long-term changes – Steinbrecht et al. (1998) “For the central European station of Hohenpeissenberg, averaging of ozone profiles grouped by tropopause height shows that the ozone mixing ratio profile in the lower stratosphere shifts up and down with the tropopause. The shift is largest near the tropopause and becomes negligible above 20 to 25 km. As a consequence a high tropopause is correlated with low total ozone and a low tropopause with high total ozone. Independent of season, total ozone decreases by 16 Dobson units (DU) per kilometer increase in tropopause height. At Hohenpeissenberg the tropopause has moved up by 150±70 m (2 σ) per decade over the last 30 years. If the −16 DU per kilometer correlation between total ozone and tropopause height is valid on the timescale of years, it is speculated that the observed increase in tropopause height could explain about 25% of the observed −10 DU per decade decrease of total ozone. This is of the same magnitude as the 30% fraction of midlatitude ozone depletion which current stratospheric models have difficulty accounting for. For Hohenpeissenberg the increase in tropopause height appears to be correlated with observed tropospheric warming: At 5 km altitude, for example, temperature has increased by 0.7±0.3 K per decade (2 σ) since 1967.” W. Steinbrecht, H. Claude, U. Köhler, K. P. Hoinka, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 103, Issue D15, pages 19183–19192, 20 August 1998, DOI: 10.1029/98JD01929.

A comparison of ozone and thermal tropopause heights and the impact of tropopause definition on quantifying the ozone content of the troposphere – Bethan et al. (1996) “A comparison has been conducted of the height and sharpness of the tropopause as revealed by temperature and ozone profiles. In the study, 628 ECC-type ozonesonde profiles from four stations in northern Europe were used. Two tropopauses were defined for each profile: a thermal tropopause and an ozone tropopause defined in terms of both mixing ratio and vertical gradient of mixing ratio. On average, the ozone tropopause lay 800 m below the thermal. Large differences in tropopause height were associated with indefinite thermal tropopauses which were, in turn, often associated with cyclonic conditions (some corresponding to profiles taken within the stratospheric polar vortex). On almost all profiles the thermal tropopause was the higher of the two, and of the 15 profiles that did not fit this pattern, two-thirds were associated with anticyclonic flow in the upper troposphere. It is also shown that the tropopause definition impacts greatly on the evaluation of the ozone content of the troposphere. Where the thermal tropopause is indefinite in character, on average 27% of the ozone found below the thermal tropopause lies above the ozone tropopause.” S. Bethan, G. Vaughan, S. J. Reid, Quarterly Journal of the Royal Meteorological Society, Volume 122, Issue 532, pages 929–944, April 1996 Part B, DOI: 10.1002/qj.49712253207.

On the Height of the Tropopause and the Static Stability of the Troposphere – Held (1982) “Speculative arguments are, presented that describe how radiative and dynamical constraints conspire to determine the height of the tropopause and the tropospheric static stability in midlatitudes and in the tropics. The arguments suggest an explanation for the observation that climatological isentropic slopes in midlatitudes are close to the critical slope required for baroclinic instability in a two-layer model.” Held, Issac M., 1982: On the Height of the Tropopause and the Static Stability of the Troposphere. J. Atmos. Sci., 39, 412–417. doi:;2. [Full text]

Quasi-Biennial Variations in Temperature, Total Ozone, and Tropopause Height – Angell & Korshover (1964) “An analysis of mean-monthly temperature and total ozone data suggests that quasi-biennial oscillations extend to the temperate and polar latitudes of both hemispheres. Basically, there is symmetry with respect to the equator, although the oscillations show up most clearly in the Southern Hemisphere, and there is a tendency for the biennial maximum of temperature and total ozone to occur in the spring. Harmonic analysis implies a poleward drift of the biennial maximum of temperature and total ozone at a rate near 0.2 m sec−1, with the drift becoming indistinct poleward of 40°. The quasi-biennial variation in total ozone is very nearly in phase with the quasi-biennial variation in 50-mb temperature. There is also a quasi-biennial variation in tropopause height associated with the temperature oscillation in the lower stratosphere. There is weak evidence for a quasi-biennial variation in beryllium-7 in the lower stratosphere.” Angell, J. K., J. Korshover, 1964: Quasi-Biennial Variations in Temperature, Total Ozone, and Tropopause Height. J. Atmos. Sci., 21, 479–492. doi:;2. [Full text]

Some ozone-weather relationships in the middle latitudes of the Southern Hemisphere – Kulkarni (1963)
The paper discusses relationships observed between ozone and the upper-air measurements made at Brisbane, Aspendale and Macquarie Island. The correlation coefficients between the short-term fluctuations of ozone and the temperatures at 100, 200 and 300 mb levels at these places are presented. In general, high ozone was observed to be associated with the sinking of the tropopause, descending of stratospheric air, warming of the lower stratosphere and a southerly flow of air in the lower stratosphere. At Macquarie Island, an instance of the ozone fluctuations in the baroclinic waves of the polar night westerly vortex suggested that the middle stratospheric waves contributed to the unexplained long term variance in total ozone. The meteorological parameters at the 200 mb level did not reveal the type of oscillation shown by the spring maximum level of ozone with a periodicity of 24 months. From the study of the 60 mb temperatures, it is concluded that the middle stratospheric circulation is playing an important role in deciding the spring level of ozone in middle latitudes of the Southern Hemisphere.” R. N. Kulkarni, Quarterly Journal of the Royal Meteorological Society, Volume 89, Issue 382, pages 478–489, October 1963, DOI: 10.1002/qj.49708938205.

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