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necessarily) drive transitions from strong to weak stable stratification. Based on the observational results discussed above, the SBL is often classified into weakly and very stably stratified regimes (respectively denoted the wSBL and vSBL; cf. Okamoto and Webb 1970 ; Kondo et al. 1978 ; Mahrt 1998 ; Acevedo and Fitzjarrald 2003 ; Shravan Kumar et al. 2012 ; Liang et al. 2014 ; Mahrt 2014 ; van Hooijdonk et al. 2015 ; Vercauteren and Klein 2015 ). Other regime classifications have been suggested
necessarily) drive transitions from strong to weak stable stratification. Based on the observational results discussed above, the SBL is often classified into weakly and very stably stratified regimes (respectively denoted the wSBL and vSBL; cf. Okamoto and Webb 1970 ; Kondo et al. 1978 ; Mahrt 1998 ; Acevedo and Fitzjarrald 2003 ; Shravan Kumar et al. 2012 ; Liang et al. 2014 ; Mahrt 2014 ; van Hooijdonk et al. 2015 ; Vercauteren and Klein 2015 ). Other regime classifications have been suggested
://www.erad2010.org/pdf/POSTER/Wednesday/03_Satellite/03_ERAD2010_0023_extended.pdf .] Herrmann , S. , and K. A. Mohr , 2011 : A continental-scale classification of rainfall seasonality regimes in Africa based on gridded precipitation and land surface temperature products . J. Appl. Meteor. Climatol. , 50 , 2504 – 2513 , doi: 10.1175/JAMC-D-11-024.1 . Hijmans , R. J. , S. E. Cameron , J. L. Parra , P. Jones , and A. Jarvis , 2005 : Very high resolution interpolated climate surfaces for
://www.erad2010.org/pdf/POSTER/Wednesday/03_Satellite/03_ERAD2010_0023_extended.pdf .] Herrmann , S. , and K. A. Mohr , 2011 : A continental-scale classification of rainfall seasonality regimes in Africa based on gridded precipitation and land surface temperature products . J. Appl. Meteor. Climatol. , 50 , 2504 – 2513 , doi: 10.1175/JAMC-D-11-024.1 . Hijmans , R. J. , S. E. Cameron , J. L. Parra , P. Jones , and A. Jarvis , 2005 : Very high resolution interpolated climate surfaces for
influence of large-scale atmospheric circulations relative to those of local processes to help explain the variability of daily temperature anomalies across France. Our study aims to quantify the relative contributions of large-scale atmospheric circulations and of local processes on the variability of temperature anomalies at three observatories located in France. For this, we shall evaluate specific issues: (i) the effect of weather regimes on daily temperature anomalies by use of the classification
influence of large-scale atmospheric circulations relative to those of local processes to help explain the variability of daily temperature anomalies across France. Our study aims to quantify the relative contributions of large-scale atmospheric circulations and of local processes on the variability of temperature anomalies at three observatories located in France. For this, we shall evaluate specific issues: (i) the effect of weather regimes on daily temperature anomalies by use of the classification
et al. 2017b ; Abraham and Monahan 2019a , b , hereafter AM19a and AM19b ). This study uses data from several tower sites in different meteorological settings to investigate the long-term occupation and transition statistics of SBL regimes. Furthermore, the relationship between external drivers and regime occupation and regime transitions are assessed. While this two-regime classification is the simplest among those that have been proposed for the SBL, we have demonstrated that it provides
et al. 2017b ; Abraham and Monahan 2019a , b , hereafter AM19a and AM19b ). This study uses data from several tower sites in different meteorological settings to investigate the long-term occupation and transition statistics of SBL regimes. Furthermore, the relationship between external drivers and regime occupation and regime transitions are assessed. While this two-regime classification is the simplest among those that have been proposed for the SBL, we have demonstrated that it provides
regimes and transitions between them are poorly represented in weather and climate models, due both to coarse resolution (vertical and horizontal) and to an imperfect understanding of all the diverse physical processes governing the SBL (e.g., Holtslag et al. 2013 ; Mahrt 2014 ). In this study the climatological evolution and structure of meteorological state variables during times of transitions between these two SBL regime states are investigated across different tower sites, and compared to state
regimes and transitions between them are poorly represented in weather and climate models, due both to coarse resolution (vertical and horizontal) and to an imperfect understanding of all the diverse physical processes governing the SBL (e.g., Holtslag et al. 2013 ; Mahrt 2014 ). In this study the climatological evolution and structure of meteorological state variables during times of transitions between these two SBL regime states are investigated across different tower sites, and compared to state
constrain the number of clusters needed to describe the cloud field and to interpret the resulting cloud structures with respect to the known features of the dynamic regime that creates a particular WS. However, it was obvious from the maps of WS distributions (e.g., Oreopoulos and Rossow 2011 ) that the derived weather states were not confined to the arbitrarily defined boundaries of these climate zones. Furthermore, such boundaries made it harder to examine variability of the weather states with
constrain the number of clusters needed to describe the cloud field and to interpret the resulting cloud structures with respect to the known features of the dynamic regime that creates a particular WS. However, it was obvious from the maps of WS distributions (e.g., Oreopoulos and Rossow 2011 ) that the derived weather states were not confined to the arbitrarily defined boundaries of these climate zones. Furthermore, such boundaries made it harder to examine variability of the weather states with
in synoptic climatological classification. J. Climate Appl. Meteor. , 26 , 717 – 730 . Kidson , J. W. , 2000 : An analysis of New Zealand synoptic types and their use in defining weather regimes. Int. J. Climatol. , 20 , 299 – 316 . Lund , R. B. , and I. V. Basawa , 2000 : Recursive prediction and likelihood evaluation for periodic ARMA models. J. Time Ser. Anal. , 21 , 75 – 93 . Lund , R. B. , and J. Reeves , 2002 : Detection of undocumented changepoints: A revision of
in synoptic climatological classification. J. Climate Appl. Meteor. , 26 , 717 – 730 . Kidson , J. W. , 2000 : An analysis of New Zealand synoptic types and their use in defining weather regimes. Int. J. Climatol. , 20 , 299 – 316 . Lund , R. B. , and I. V. Basawa , 2000 : Recursive prediction and likelihood evaluation for periodic ARMA models. J. Time Ser. Anal. , 21 , 75 – 93 . Lund , R. B. , and J. Reeves , 2002 : Detection of undocumented changepoints: A revision of
consideration of all types of cyclones together. Separating out different classes may lead to added insight into the representation of these features in models. The objective classification method described here offers a way of grouping cyclones using atmospheric variables that are widely available from climate model simulations. Manual techniques are impractical for long periods and for multiple models, and they are also not a repeatable methodology—a different synoptic practitioner may place the cyclones
consideration of all types of cyclones together. Separating out different classes may lead to added insight into the representation of these features in models. The objective classification method described here offers a way of grouping cyclones using atmospheric variables that are widely available from climate model simulations. Manual techniques are impractical for long periods and for multiple models, and they are also not a repeatable methodology—a different synoptic practitioner may place the cyclones
, and K. Okamoto , 2004 : On rain type classification algorithm TRMM PR 2A23 V6. Proc. Second TRMM Int. Science Conf., Nara, Japan, JAXA, NICT, and NASA, 1.3 . Awaka , J. , T. Iguchi , and K. Okamoto , 2007 : Measuring Precipitation from Space: EURAINSAT and the Future . Springer, 748 pp . Battan , L. J. , 1973 : Radar Observation of the Atmosphere . University of Chicago Press, 324 pp . Berg , W. , T. L’Ecuyer , and C. Kummerow , 2006 : Rainfall climate regimes: The
, and K. Okamoto , 2004 : On rain type classification algorithm TRMM PR 2A23 V6. Proc. Second TRMM Int. Science Conf., Nara, Japan, JAXA, NICT, and NASA, 1.3 . Awaka , J. , T. Iguchi , and K. Okamoto , 2007 : Measuring Precipitation from Space: EURAINSAT and the Future . Springer, 748 pp . Battan , L. J. , 1973 : Radar Observation of the Atmosphere . University of Chicago Press, 324 pp . Berg , W. , T. L’Ecuyer , and C. Kummerow , 2006 : Rainfall climate regimes: The
the physical processes involved in the banded rainfall. The next step will be to identify the weather types associated with BOC events and to study how they may be affected by climate change. Acknowledgments The French national LEFE/IDAO and EC2CO/CYTRIX programs of INSU supported the current study. Météo-France, the University of Wyoming, and the OHMCV provided data. The authors thank Bruno Joly from Météo-France who helped us in the use and interpretation of the weather-type classification
the physical processes involved in the banded rainfall. The next step will be to identify the weather types associated with BOC events and to study how they may be affected by climate change. Acknowledgments The French national LEFE/IDAO and EC2CO/CYTRIX programs of INSU supported the current study. Météo-France, the University of Wyoming, and the OHMCV provided data. The authors thank Bruno Joly from Météo-France who helped us in the use and interpretation of the weather-type classification