In this study,the Betts-Miller-Janjic(BMJ)convective adjustment scheme in the Weather Research and Forecasting(WRF)model version 4.0 was used to investigate the effect of itsα-parameter,which influences the first-gue...In this study,the Betts-Miller-Janjic(BMJ)convective adjustment scheme in the Weather Research and Forecasting(WRF)model version 4.0 was used to investigate the effect of itsα-parameter,which influences the first-guess potential temperature reference profile on the Madden-Julian oscillation(MJO)propagation and structure.This study diagnosed the MJO active phase composites of the MJO-filtered outgoing longwave radiation(OLR)during the December-to-February(DJF)period of 2006-2016 over the Indian Ocean(IO),Maritime Continent(MC),and western Pacific(WP).The results show that the MJO-filtered OLR intensity,propagation pattern,and MJO classification(standing,jumping,and propagating clusters)are sensitive to theα-value,but the phase speeds of propagating MJOs are not.Overall,with an increasingα-value,the simulated MJO-filtered OLR intensity increases,and the simulated propagation pattern is improved.Results also show that the intensity and propagation pattern of an eastward-propagating MJO are associated with MJO circulation structures and thermodynamic structures.Asαincreases,the front Walker cell and the low-level easterly anomaly are enhanced,which premoistens the lower troposphere and triggers more active shallow and congestus clouds.The enhanced shallow and congestus convection preconditions the lower to middle troposphere,accelerating the transition from congestus to deep convection,thereby facilitating eastward propagation of the MJO.Therefore,the simulated MJO tends to transfer from standing to eastward propagating asαincreases.In summary,increasing theα-value is a possible way to improve the simulation of the structure and propagation of the MJO.展开更多
BMJ are delighted to be working in partnership with Shanghai Medical Health Centre （SMHC） to bring General Psychiatry to an international audience. With our shared aim of improving healthcare and patient outcomes, w...BMJ are delighted to be working in partnership with Shanghai Medical Health Centre （SMHC） to bring General Psychiatry to an international audience. With our shared aim of improving healthcare and patient outcomes, we will be working to continue to grow the journal by attracting the best international authors and providing quality research to a worldwide readership of mental healthcare professionals.展开更多
Family Medicine and Community Health(FMCH)是在中国创刊的第一本全科医学国际学术期刊,由中国全科医学杂志社主办,英国BMJ 出版集团发行。其以全人健康(whole people health)和人群健康(population health)为出发点,以家庭医学和社...Family Medicine and Community Health(FMCH)是在中国创刊的第一本全科医学国际学术期刊,由中国全科医学杂志社主办,英国BMJ 出版集团发行。其以全人健康(whole people health)和人群健康(population health)为出发点,以家庭医学和社区健康领域的行业发展和科学研究为重心,以这些领域的研究者、教育家、政策制定者和领导者为主要读者群,致力于在世界范围内传播全科医学研究和推动学科发展,成为帮助发达国家和发展中国家的研究者交流学术、分享有效经验和证据的桥梁和平台。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41975090,U2242201,42075077)the Natural Science Foundation of Hunan Province,China(2022JJ20043)the Science and Technology Innovation Program of Hunan Province,China(2022RC1239)。
文摘In this study,the Betts-Miller-Janjic(BMJ)convective adjustment scheme in the Weather Research and Forecasting(WRF)model version 4.0 was used to investigate the effect of itsα-parameter,which influences the first-guess potential temperature reference profile on the Madden-Julian oscillation(MJO)propagation and structure.This study diagnosed the MJO active phase composites of the MJO-filtered outgoing longwave radiation(OLR)during the December-to-February(DJF)period of 2006-2016 over the Indian Ocean(IO),Maritime Continent(MC),and western Pacific(WP).The results show that the MJO-filtered OLR intensity,propagation pattern,and MJO classification(standing,jumping,and propagating clusters)are sensitive to theα-value,but the phase speeds of propagating MJOs are not.Overall,with an increasingα-value,the simulated MJO-filtered OLR intensity increases,and the simulated propagation pattern is improved.Results also show that the intensity and propagation pattern of an eastward-propagating MJO are associated with MJO circulation structures and thermodynamic structures.Asαincreases,the front Walker cell and the low-level easterly anomaly are enhanced,which premoistens the lower troposphere and triggers more active shallow and congestus clouds.The enhanced shallow and congestus convection preconditions the lower to middle troposphere,accelerating the transition from congestus to deep convection,thereby facilitating eastward propagation of the MJO.Therefore,the simulated MJO tends to transfer from standing to eastward propagating asαincreases.In summary,increasing theα-value is a possible way to improve the simulation of the structure and propagation of the MJO.
文摘BMJ are delighted to be working in partnership with Shanghai Medical Health Centre （SMHC） to bring General Psychiatry to an international audience. With our shared aim of improving healthcare and patient outcomes, we will be working to continue to grow the journal by attracting the best international authors and providing quality research to a worldwide readership of mental healthcare professionals.
文摘Family Medicine and Community Health(FMCH)是在中国创刊的第一本全科医学国际学术期刊,由中国全科医学杂志社主办,英国BMJ 出版集团发行。其以全人健康(whole people health)和人群健康(population health)为出发点,以家庭医学和社区健康领域的行业发展和科学研究为重心,以这些领域的研究者、教育家、政策制定者和领导者为主要读者群,致力于在世界范围内传播全科医学研究和推动学科发展,成为帮助发达国家和发展中国家的研究者交流学术、分享有效经验和证据的桥梁和平台。
