The Tropical Tropopause Layer 1960–2100

The representation of the Tropical Tropopause Layer (TTL) in 13 different Chemistry Climate Models (CCMs) designed to represent the stratosphere is analyzed. Simulations for 1960–2005 and 1980–2100 are analyzed. Simulations for 1960–2005 are compared to reanalysis model output. CCMs are able to reproduce the basic structure of the TTL. There is a large (10 K) spread in annual mean tropical cold point tropopause temperatures. CCMs are able to reproduce historical trends in tropopause pressure obtained from reanalysis products. Simulated historical trends in cold point tropopause temperatures are not consistent across models or reanalyses. The pressure of both the tropical tropopause and the level of main convective outflow appear to have decreased (increased altitude) in historical runs as well as in reanalyses. Decreasing pressure trends in the tropical tropopause and level of main convective outflow are also seen in the future. Models consistently predict decreasing tropopause and convective outflow pressure, by several hPa/decade. Tropical cold point temperatures are projected to increase by 0.09 K/decade. Tropopause anomalies are highly correlated with tropical surface temperature anomalies and with tropopause level ozone anomalies, less so with stratospheric temperature anomalies. Simulated stratospheric water vapor at 90 hPa increases by up to 0.5–1 ppmv by 2100. The result is consistent with the simulated increase in temperature, highlighting the correlation of tropopause temperatures with stratospheric water vapor.

[1]  L. Polvani,et al.  The impact of stratospheric ozone recovery on tropopause height trends. , 2009 .

[2]  F. Lott,et al.  The coupled chemistry-climate model LMDz-REPROBUS: description and evaluation of a transient simulation of the period 1980–1999 , 2008 .

[3]  A. Gettelman,et al.  Insights into Tropical Tropopause Layer processes using global models , 2007 .

[4]  Dian J. Seidel,et al.  Recent widening of the tropical belt: Evidence from tropopause observations , 2007 .

[5]  Q. Fu,et al.  Observed poleward expansion of the Hadley circulation since 1979 , 2007 .

[6]  C. Brühl,et al.  Multimodel projections of stratospheric ozone in the 21st century , 2007 .

[7]  Rolando R. Garcia,et al.  Simulation of secular trends in the middle atmosphere, 1950–2003 , 2007 .

[8]  J. Austin,et al.  Evolution of Water Vapor Concentrations and Stratospheric Age of Air in Coupled Chemistry-Climate Model Simulations , 2007 .

[9]  Susan A. Murphy,et al.  Monographs on statistics and applied probability , 1990 .

[10]  Q. Fu,et al.  Widening of the tropical belt in a changing climate , 2007 .

[11]  Q. Fu,et al.  Observed poleward expansion of the Hadley circulation since 1979 , 2007 .

[12]  Andrew Gettelman,et al.  The global impact of supersaturation in a coupled chemistry-climate model , 2006 .

[13]  Volker Grewe,et al.  Assessment of temperature, trace species, and ozone in chemistry-climate model simulations of the recent past , 2006 .

[14]  D. Seidel,et al.  Variability and trends in the global tropopause estimated from radiosonde data , 2006 .

[15]  J. Austin,et al.  Ensemble simulations of the decline and recovery of stratospheric ozone , 2006 .

[16]  Adam A. Scaife,et al.  Simulations of anthropogenic change in the strength of the Brewer–Dobson circulation , 2006 .

[17]  S. Bony,et al.  How Well Do We Understand and Evaluate Climate Change Feedback Processes , 2006 .

[18]  Theodore G. Shepherd,et al.  The tropopause inversion layer in models and analyses , 2006 .

[19]  Holger Vömel,et al.  Decreases in stratospheric water vapor after 2001: Links to changes in the tropical tropopause and the Brewer‐Dobson circulation , 2006 .

[20]  W. G. Strand,et al.  Climate Change Projections for the Twenty-First Century and Climate Change Commitment in the CCSM3 , 2006 .

[21]  Qiang Fu,et al.  Enhanced Mid-Latitude Tropospheric Warming in Satellite Measurements , 2006, Science.

[22]  W. Norton,et al.  Tropical Wave Driving of the Annual Cycle in Tropical Tropopause Temperatures. Part I: ECMWF Analyses , 2006 .

[23]  Michel Crucifix,et al.  The new hadley centre climate model (HadGEM1) : Evaluation of coupled simulations , 2006 .

[24]  Steven Pawson,et al.  Trends in Stratospheric Ozone: Lessons Learned from a 3D Chemical Transport Model , 2006 .

[25]  M. Dameris,et al.  Solar cycle effect delays onset of ozone recovery , 2006 .

[26]  S. Fueglistaler,et al.  Control of interannual and longer‐term variability of stratospheric water vapor , 2005 .

[27]  T. Nakajima,et al.  Effects of atmospheric sphericity on stratospheric chemistry and dynamics over Antarctica , 2005 .

[28]  F. Hourdin,et al.  The stratospheric version of LMDz: dynamical climatologies, arctic oscillation, and impact on the surface climate , 2005 .

[29]  A. Sterl,et al.  The ERA‐40 re‐analysis , 2005 .

[30]  Jeffrey H. Yin,et al.  A consistent poleward shift of the storm tracks in simulations of 21st century climate , 2005 .

[31]  W. Collins,et al.  Amplification of Surface Temperature Trends and Variability in the Tropical Atmosphere , 2005, Science.

[32]  C. Brühl,et al.  Long-term changes and variability in a transient simulation with a chemistry-climate model employing realistic forcing , 2005 .

[33]  E. Manzini,et al.  Chemistry-climate model SOCOL: a validation of the present-day climatology , 2005 .

[34]  M. Deushi,et al.  Partitioning between resolved wave forcing and unresolved gravity wave forcing to the quasi‐biennial oscillation as revealed with a coupled chemistry‐climate model , 2005 .

[35]  Michael G. Bosilovich,et al.  Documentation and Validation of the Goddard Earth Observing System (GEOS) Data Assimilation System, Version 4 , 2005 .

[36]  G. Stephens.  Cloud Feedbacks in the Climate System: A Critical Review , 2005 .

[37]  A. Ohmura,et al.  Assessment of the ozone and temperature variability during 1979-1993 with the chemistry-climate model SOCOL , 2005 .

[38]  Kiyotaka Shibata,et al.  Development of an MRI Chemical Transport Model for the Study of Stratospheric Chemistry , 2005 .

[39]  M. Chipperfield,et al.  A new coupled chemistry–climate model for the stratosphere: The importance of coupling for future O3‐climate predictions , 2005 .

[40]  K. Kreher,et al.  Past and future simulations of NO 2 from a coupled chemistry-climate model in comparison with observations , 2004 .

[41]  Fei Wu,et al.  Interannual changes of stratospheric water vapor and correlations with tropical tropopause temperatures , 2004 .

[42]  H. Akiyoshi,et al.  Ozone perturbations in the Arctic summer lower stratosphere as a reflection of NOX chemistry and planetary scale wave activity , 2004 .

[43]  J. Austin,et al.  Coupled chemistry–climate model simulations for the period 1980 to 2020: Ozone depletion and the start of ozone recovery , 2003 .

[44]  C. Brühl,et al.  A new interactive chemistry-climate model: 2. Sensitivity of the middle atmosphere to ozone depletion and increase in greenhouse gases and implications for recent stratospheric cooling , 2003 .

[45]  R. Sausen,et al.  Contributions of Anthropogenic and Natural Forcing to Recent Tropopause Height Changes , 2003, Science.

[46]  J. Lelieveld,et al.  A new interactive chemistry-climate model: 1. Present-day climatology and interannual variability of the middle atmosphere using the model and 9 years of HALOE/UARS data , 2003 .

[47]  P. Forster,et al.  A Climatology of the Tropical Tropopause Layer , 2002 .

[48]  P. Forster,et al.  Assessing the climate impact of trends in stratospheric water vapor , 2002 .

[49]  D. Shindell,et al.  Impact of Future Climate and Emission Changes on Stratospheric Aerosols and Ozone , 2002 .

[50]  G. Craig,et al.  On the temperature structure of the tropical substratosphere , 2002 .

[51]  J. Austin.  A Three-Dimensional Coupled Chemistry–Climate Model Simulation of Past Stratospheric Trends , 2002 .

[52]  S. Massie,et al.  Transport of water vapor in the tropical tropopause layer , 2002 .

[53]  J. Russell,et al.  El niño as a natural experiment for studying the tropical tropopause region , 2001 .

[54]  A. Gettelman,et al.  Horizontal transport and the dehydration of the stratosphere , 2001 .

[55]  D. Seidel,et al.  Climatological characteristics of the tropical tropopause as revealed by radiosondes , 2001 .

[56]  J. C. McConnell,et al.  Ozone climatology using interactive chemistry: Results from the Canadian Middle Atmosphere Model , 2000 .

[57]  M. Fiorino,et al.  A comparison of reanalyses in the tropical stratosphere. Part 3: inclusion of the pre-satellite data era , 1999 .

[58]  T. Shepherd,et al.  Radiative‐dynamical climatology of the first‐generation Canadian middle atmosphere model , 1997 .

[59]  Michael Seablom,et al.  Technical report series on global modeling and data assimilation. Volume 4: Documentation of the Goddard Earth Observing System (GEOS) data assimilation system, version 1 , 1995 .

[60]  R. Tibshirani,et al.  An Introduction to the Bootstrap , 1995 .