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1.
P. L. S. Rao U. C. Mohanty P. V. S. Raju Gopal Iyengar 《Journal of Earth System Science》2003,112(1):95-111
In this study, we present the mean seasonal features of the Indian summer monsoon circulation in the National Centre for Medium
Range Weather Forecasting (NCMRWF) global data assimilation and forecast system. The large-scale budgets of heat and moisture
are examined in the analyzed and model atmosphere. The daily operational analyses and forecasts (day 1 through day 5) produced
for the summer seasons comprising June, July and August of 1995 and 1993 have been considered for the purpose. The principal
aim of the study is two-fold. Primarily, to comprehend the influence of the systematic errors over the Indian summer monsoon,
secondarily, to analyze the performance of the model in capturing the interseasonal variability.
The heat and moisture balances show reduction in the influx of heat and moisture in the model forecasts compared to the analyzed
atmosphere over the monsoon domain. Consequently, the diabatic heating also indicates reducing trend with increase in the
forecast period. In effect, the strength of Indian summer monsoon, which essentially depends on these parameters, weakens
considerably in the model forecasts. Despite producing feeble monsoon circulation, the model captures interseasonal variability
realistically. Although, 1995 and 1993 are fairly normal monsoon seasons, the former received more rainfall compared to the
latter in certain pockets of the monsoon domain. This is clearly indicated by the analyzed and model atmosphere in terms of
energetics. 相似文献
2.
In this article, the interannual variability of certain dynamic and thermodynamic characteristics of various sectors in the
Asian summer monsoon domain was examined during the onset phase over the south Indian peninsula (Kerala Coast). Daily average
(0000 and 1200 UTC) reanalysis data sets of the National Centre for Environmental Prediction/National Centre for Atmospheric
Research (NCEP/NCAR) for the period 1948–1999 were used. Based on 52 years onset date of the Indian summer monsoon, we categorized
the pre-onset, onset, and post-onset periods (each an average of 5 days) to investigate the interannual variability of significant
budget terms over the Arabian Sea, Bay of Bengal, and the Indian peninsula. A higher difference was noticed in low-level kinetic
energy (850 hPa) and the vertically integrated generation of kinetic energy over the Arabian Sea from the pre-onset, onset,
and post-onset periods. Also, significant changes were noticed in the net tropospheric moisture and diabatic heating over
the Arabian Sea and Indian peninsula from the pre-onset to the post-onset period. It appears that attaining the magnitude
of 40 m2 s−2 and then a sharp rise in kinetic energy at 850 hPa is an appropriate time to declare the onset of the summer monsoon over
India. In addition to a sufficient level of net tropospheric moisture (40 mm), a minimum strength of low-level flow is needed
to trigger convective activity over the Arabian Sea and the Bay of Bengal. An attempt was also made to develop a location-specific
prediction of onset dates of the summer monsoon over India based on energetics and basic meteorological parameters using multivariate
statistical techniques. The regression technique was developed with the data of May and June for 42 years (1948–1989) and
validated with 10 years NCEP reanalysis from 1990 to 1999. It was found that the predicted onset dates from the regression
model are fairly in agreement with the observed onset dates obtained from the Indian Meteorology Department. 相似文献
3.
Marina Aloysius S Sijikumar S S Prijith Mannil Mohan K Parameswaran 《Journal of Earth System Science》2011,120(2):269-279
The circulation dynamics of an event marked by the formation of an aerosol cluster off the coast of Maharashtra on April 22,
2006, its southward migration along the Indian west coast with a mean speed of ~200 km/day and its final dissipation after
reaching the end of the peninsula by April 28, 2006 as revealed by MODIS (Moderate Resolution Imaging Spectroradiometer) against
the pre-monsoon conditions of April 2006 are examined in this study. The maximum aerosol concentration in the cluster was
found getting confined to lower and lower altitudes during its southward movement. The NCEP/NCAR (National Centers for Environmental
Prediction/National Center for Atmospheric Research) reanalysis wind field indicates that the atmospheric circulation, especially
the horizontal wind convergence is the major factor that guides the formation and the dynamics of the cluster. Fine mode fraction
from MODIS suggests that the cluster mainly consists of coarse dust particles. The regional climate model, RegCM3 with an
efficient dust generation module simulates the formation and movement of the cluster appreciably well. The simulations which
also exhibit the altitudinally descending nature of the cluster during its southward movement confirm the mechanism which
governs the cluster dynamics suggested based on MODIS and NCEP/NCAR reanalysis data. 相似文献
4.
The role of intraseasonal oscillations (ISOs) in modulating synoptic and interannual variations of surface winds over the
Indian monsoon region is studied using daily averaged National Centers for Environmental Prediction/National Centre for Atmospheric
Research (NCEP/NCAR) reanalyses for the period 1987–1996. Two dominant ISOs are found in all years, with a period between
30–60 days and 10–20 days respectively. Although the ISOs themselves explain only about 10–25% of the daily variance, the
spatial structure of variance of the ISOs is found to be nearly identical to that of high frequency activity (synoptic disturbances),
indicating a significant control by the ISOs in determining the synoptic variations. Zonal and meridional propagation characteristics
of the two modes and their interannual variability are studied in detail.
The synoptic structure of the 30–60 day mode is similar in all years and is shown to be intimately related to the strong (‘active’)
or weak (‘break’) phases of the Indian summer monsoon circulation. The peak (trough) phase of the mode in the north Bay of
Bengal corresponds to the ‘active’ (‘break’) phase of monsoon strengthening (weakening) the entire large scale monsoon circulation.
The ISOs modulate synoptic activity through the intensification or weakening of the large scale monsoon flow (monsoon trough).
The peak wind anomalies associated with these ISOs could be as large as 30% of the seasonal mean winds in many regions. The
vorticity pattern associated with the 30–60 day mode has a bi-modal meridional structure similar to the one associated with
the seasonal mean winds but with a smaller meridional scale. The spatial structure of the 30–60 day mode is consistent with
fluctuations of the tropical convergence zone (TCZ) between one continental and an equatorial Indian Ocean position. The 10–20
day mode has maximum amplitude in the north Bay of Bengal, where it is comparable to that of the 30–60 day mode. Elsewhere
in the Indian Ocean, this mode is almost always weaker than the 30–60 day mode. In the Bay of Bengal region, the wind curl
anomalies associated with the peak phases of the ISOs could be as large as 50% of the seasonal mean wind curl. Hence, ISOs
in this region could drive significant ISOs in the ocean and might influence the seasonal mean currents in the Bay.
On the interannual time scale, the NCEP/NCAR reanalysed wind stress is compared with the Florida State University monthly
mean stress. The seasonal mean stress as well as interannual standard deviation of monthly stress from the two analyses agree
well, indicating absence of any serious systematic bias in the NCEP/NCAR reanalysed winds. It is also found that the composite
structure of the 30–60 day mode is strikingly similar to the dominant mode of interannual variability of the seasonal mean
winds indicating a strong link between the ISOs and the seasonal mean. The ISO influences the seasonal mean and its interannual
variability either through increased/decreased residence time of the TCZ in the continental position or through occurrence
of stronger/weaker active/break spells. Thus, the ISOs seem to modulate all variability in this region from synoptic to interannual
scales. 相似文献
5.
This paper investigates the characteristic features of the coastal atmospheric boundary layer (CABL) along the west coast
of India during the south-west monsoon (SWM) 2002. Extensive surface and upper-air findings were obtained during the same
period from the Arabian Sea Monsoon Experiment (ARMEX; 15th June to 15th August 2002) 2002. The operational general circulation
model (GCM) of the National Centre for Medium Range Weather Forecasting (NCMRWF) was used in this study to see the spatial
variation of the CABL during two specific convective episodes that led to heavy rainfall along the west coast of India. The
impact of a non-local closure (NLC) scheme employed in the NCMRWF GCM was carried out in simulating the CABL. The same episodes
were also simulated using a similar parameterization scheme employed in the high resolution mesoscale modelling system (MM5).
The diurnal variation of CABL is better represented from MM5 simulation. Comparing the MM5 simulation with that of the coarser
grid NCMRWF GCM, we observed that the NCMRWF GCM underestimates the values of both latent heat flux (LHF) and the coastal
atmospheric boundary layer height (CABLH). Results from MM5 therefore indicate that the best way to move forward in addressing
the short-comings of coarse grid-scale GCMs is to provide a parameterization of the diurnal effects associated with convection
processes. 相似文献
6.
Long range prediction of Indian summer monsoon rainfall 总被引：3，自引：0，他引：3
The search for new parameters for predicting the all India summer monsoon rainfall (AISMR) has been an important aspect of long range prediction of AISMR. In recent years NCEP/NCAR reanalysis has improved the geographical coverage and availability of the data and this can be easily updated. In this study using NCEP/NCAR reanalysis data on temperature, zonal and meridional wind at different pressure levels, few predictors are identified and a prediction scheme is developed for predicting AISMR. The regression coefficients are computed by stepwise multiple regression procedure. The final equation explained 87% of the variance with multiple correlation coefficient (MCC), 0.934. The estimated rainfall in the El-Niño year of 1997 was ?1.7% as against actual of 4.4%. The estimated rainfall deficiency in both the recent deficient years of 2002 and 2004 were ?19.5% and ?8.5% as against observed ?20.4% and ?11.5% respectively. 相似文献
7.
8.
提出了确定东亚夏季风活动区域、划分热带季风和副热带季风活动区域的指标,利用大气对流层风速、位势高度、湿度、温度、OLR以及TBB等NCEP/NCAR资料,从月、候和过程平均多种时间尺度,诊断分析了2005年6月(简称“0506”)华南持续性暴雨的季风环流活动变化特征.结果表明:副热带高压强度偏强,西脊点位置偏西偏南,热带西太平洋(130°～140°E)区域越赤道气流偏强,华南处于气旋性低压异常区,无论是月时间尺度还是暴雨过程时间尺度都表现出这些明显特征;暴雨过程水汽除了来源于孟加拉湾和南海外,水汽通量异常部分主要来自南海和热带西太平洋,热带西太平洋水汽随着副高边缘气流经过南海向华南输送,从而为暴雨过程提供了丰富的水汽来源;2005年6月热带季风前沿在华南沿海地区停滞时间比气候平均偏长(2候),该特征是华南暴雨预报值得参考的信号;6月整个南海地区平均季风偏强,主要体现于经向风明显偏强,但华南持续性暴雨过程开始于南海地区夏季风非活跃期,这与热带季风季节内振荡向北传播到华南有关.以上季风活动变化特征为华南强降水提供了有利的动力条件和丰富的水汽来源. 相似文献
9.
Although previous literature have considered Southern Oscillation Index (SOI), Indian Dipole, and SST as the major teleconnection patterns to explain the variability of summer monsoon rainfall over India. South Asia low pressure and Indian Ocean high are the centers of action that dominates atmospheric circulations in Indian continent. This paper examines the possible impact of South Asian low pressure distribution on the variability of summer monsoon rainfall of India using centers of action approach. Our analysis demonstrates that the explanation of summer monsoon rainfall variability over Central India is improved significantly if the SOI is replaced by South Asian low heat. This contribution also explains the physical mechanisms to establish the relationships between the South Asian low heat and regional climate by examining composite maps of large-scale circulation fields using NCEP/NCAR Reanalysis data. 相似文献
10.
青海省冬季气温变化成因及其预测方法探讨 总被引：1，自引：1，他引：0
利用青海省1961-2012年冬季气温观测资料、美国环境预报中心(NCEP)和国家大气研究中心(NCAR)月平均高度场再分析资料、国家气候中心和美国国家海洋局和大气管理局提供的126项环流指数, 探讨青海冬季气温变化特征及成因. 结果表明: 1961-2012年青海冬季气温呈显著上升趋势并具明显的年代际变化特征, 于1986年出现由冷向暖的明显转折; 西伯利亚高压、东亚冬季风是影响青海冬季气温的主要系统. 当冬季北半球500 hPa高度场出现欧亚(EU)遥相关型时, 青海冬季易于偏冷, 同时发现大西洋欧洲区极涡强度和赤道太平洋海域海温与东亚冬季风的强弱有密切关系. 采用主成分回归集成方法初步建立青海冬季气温预测模型, 经历史回报检验其距平符号一致率为87%, 具备一定预报技巧和能力. 相似文献
11.
Ananda K. Das U. C. Mohanty Someshwar Das M. Manual S. R. Kalsi 《Journal of Earth System Science》2003,112(2):165-184
The skill and efficiency of a numerical model mostly varies with the quality of initial values, accuracy on parameterization
of physical processes and horizontal and vertical resolution of the model. Commonly used low-resolution reanalyses are hardly
able to capture the prominent features associated with organized convective processes in a monsoon depression. The objective
is to prepare improved high-resolution analysis by the use of MM5 modelling system developed by the Pennsylvania State University/National
Center for Atmospheric Research (PSU/NCAR). It requires the objective comparison of high and low-resolution analysis datasets
in assessing the specific convective features of a monsoon depression. For this purpose, reanalysis datasets of NCAR/NCEP
(National Center for Atmospheric Research/National Centers for Environmental Prediction) at a horizontal resolution of 2.5‡
(latitude/longitude) have been used as first guess in the objective analysis scheme. The additional asynoptic datasets obtained
during BOBMEX-99 are utilized within the assimilation process. Cloud Motion Wind (CMW) data of METEOSAT satellite and SSM/I
surface wind data are included for the improvement of derived analysis. The multiquadric (MQD) interpolation technique is
selected and applied for meteorological objective analysis at a horizontal resolution of 30 km. After a successful inclusion
of additional data, the resulting reanalysis is able to produce the structure of convective organization as well as prominent
synoptic features associated with monsoon depression. Comparison and error verifications have been done with the help of available
upper-air station data. The objective verification reveals the efficiency of the analysis scheme. 相似文献
12.
4种再分析气温资料在羌塘国家级自然保护区的适用性研究 总被引：1，自引：0，他引：1
利用1979 - 2018年羌塘国家级自然保护区边缘的3个气象站点狮泉河（西部）、 申扎（中部）和安多（东部）的观测气温（OT）, 与ERA-Interim（ET）、 NCEP/NCAR（NT1）、 NCEP/DOE（NT2）和JRA-55（JT）4种再分析气温资料, 从年际变化和年变化两方面采用多年气温变化趋势、 均方差、 相关性等参数方法在羌塘自然保护区进行了适用性研究。结果表明： 从多年平均气温年际变化来看, 4种再分析资料在狮泉河（西部）的适用性较差, JRA-55资料在安多（东部）和申扎（中部）的适用性较好, 且冬季再分析气温资料与观测气温的相关性好于夏季; 从多年平均气温年变化来看, 均表现为冬季（1月或12月）最低, 夏季（7月或8月）最高的“单峰型”变化。综合来看, JRA-55资料在羌塘自然保护区的适用性较好, ERA-Interim对多年气温趋势变化表现不准确, NCEP/NCAR和NCEP/DOE与观测气温相比显著偏低。 相似文献
13.
夏季青藏高原加热和环流场的日变化 总被引：3，自引：0，他引：3
通过使用NCEP/NCAR再分析资料,分析了夏季青藏高原地区非绝热加热场的日变化特征以及高原上空环流场的日变化特点。分析发现青藏高原及其邻近地区上空环流的日变化在欧亚地区大气环流系统中表现最为显著。环流日变化是被非绝热加热的日变化所驱动的,特别是被太阳辐射日变化所驱动。由于高原上空大气柱质量远小于低海拔的平原地区,故太阳辐射日变化引起的加热日变化可在高原地区产生更为显著的环流日变化。通过位涡方程的诊断证实,白天高原加热增强,可在大气上层制造大量负位涡并向周边地区辐散,使高原地区大气高层成为负涡源。而低层则是加热制造正位涡,并使周边地区向高原的辐合增强,摩擦耗散是低层抑制正位涡增长的主要因素。而夜间加热减弱使高原对局地环流的影响作用大为减弱。故而高原及其周边地区的局地环流也具有明显的日变化特征。 相似文献
14.
选用海河流域1961~2012年132站逐日降水资料,通过趋势分析、M-K检验、EOF和REOF等方法分析了50余年海河流域暴雨的气候统计特征。利用NCEP/NCAR再分析资料和历史天气图资料,研究了海河流域14个典型强致灾暴雨过程的大气环流特征。结果表明:(1)海河流域夏季暴雨日站数和暴雨量的时空分布相近,暴雨日站数下降趋势较为显著;(2)海河流域夏季暴雨的空间分布可划分为3个分布型态:西南型、东北型和东南型;(3)海河流域暴雨在20世纪70年代末至80年代初存在一次突变现象;(4)海河流域强致灾暴雨过程可归纳为5类主要环流型,即高空低槽型、高空冷涡型、副高外围切变线型、低空低涡型和台风北上型。 相似文献
15.
水汽输送对雅鲁藏布江流域降水中稳定同位素的影响 总被引：1，自引：0，他引：1
利用NCEP/NCAR全球大气再分析格点资料和2005年西藏雅鲁藏布江流域4个站点（拉孜、奴各沙、羊村和奴下）降水中δ18O数据，分析了雅鲁藏布江流域降水中δ18O变化同水汽输送通量的关系。从空间上来看，雅鲁藏布江流域降水中δ18O同水汽输送通量呈明显的正相关，从下游至上游，随着水汽输送通量的减少，降水中的δ18O逐渐降低；从时间上来看，春季水汽通量较小，降水中的δ18O较高，而在夏季，水汽通量大，降水中的δ18O较低。在此基础上，又利用NCEP/NCAR气象数据建立水汽追踪模型，以羊村站为例对雅鲁藏布江流域降水的水汽输送过程进行了追踪模拟，并讨论了降水中δ18O变化同水汽源地以及输送过程的关系。结果发现，在季风降水之前的春季，降水中较高的δ18O主要受西风带水汽输送以及当地蒸发水汽的影响；在季风期间，降水中较低的δ18O主要受来自印度洋暖湿水汽输送的影响。
相似文献
16.
Meteorological fields variability over the Indian seas in pre and summer monsoon months during extreme monsoon seasons 总被引：1，自引：0，他引：1
U. C. Mohanty R. Bhatla P. V. S. Raju O. P. Madan A. Sarkar 《Journal of Earth System Science》2002,111(3):365-378
In this study, the possible linkage between summer monsoon rainfall over India and surface meteorological fields (basic fields
and heat budget components) over monsoon region (30‡E-120‡E, 30‡S30‡N) during the pre-monsoon month of May and summer monsoon
season (June to September) are examined. For this purpose, monthly surface meteorological fields anomaly are analyzed for
42 years (1958-1999) using reanalysis data of NCEP/NCAR (National Center for Environmental Prediction/National Center for
Atmospheric Research). The statistical significance of the anomaly (difference) between the surplus and deficient monsoon
years in the surface meteorological fields are also examined by Student’s t-test at 95% confidence level.
Significant negative anomalies of mean sea level pressure are observed over India, Arabian Sea and Arabian Peninsular in the
pre-monsoon month of May and monsoon season. Significant positive anomalies in the zonal and meridional wind (at 2 m) in the
month of May are observed in the west Arabian Sea off Somali coast and for monsoon season it is in the central Arabian Sea
that extends up to Somalia. Significant positive anomalies of the surface temperature and air temperature (at 2 m) in the
month of May are observed over north India and adjoining Pakistan and Afghanistan region. During monsoon season this region
is replaced by significant negative anomalies. In the month of May, significant positive anomalies of cloud amount are observed
over Somali coast, north Bay of Bengal and adjoining West Bengal and Bangladesh. During monsoon season, cloud amount shows
positive anomalies over NW India and north Arabian Sea.
There is overall reduction in the incoming shortwave radiation flux during surplus monsoon years. A higher magnitude of latent
heat flux is also found in surplus monsoon years for the month of May as well as the monsoon season. The significant positive
anomaly of latent heat flux in May, observed over southwest Arabian Sea, may be considered as an advance indicator of the
possible behavior of the subsequent monsoon season. The distribution of net heat flux is predominantly negative over eastern
Arabian Sea, Bay of Bengal and Indian Ocean. Anomaly between the two extreme monsoon years in post 1980 (i.e., 1988 and 1987)
shows that shortwave flux, latent heat flux and net heat flux indicate reversal in sign, particularly in south Indian Ocean.
Variations of the heat budget components over four smaller sectors of Indian seas, namely Arabian Sea, Bay of Bengal and west
Indian Ocean and east Indian Ocean show that a small sector of Arabian Sea is most dominant during May and other sectors showing
reversal in sign of latent heat flux during monsoon season. 相似文献
17.
The Indian subcontinent is characterized by complex topography and heterogeneous land use-land cover. The Himalayas and the Tibetan Plateau are spread across the northern part of the continent. Due to its highly variable topography, understanding of the prevailing synoptic weather systems is complex over the region. The present study analyzes the energetics of Indian winter monsoon (IWM) over the Indian subcontinent using outputs of mesoscale model (MM5) forced with National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), US, initial and boundary conditions. MM5 modeling framework, designed to simulate or predict mesoscale atmospheric circulations, is having a limited-area, non-hydrostatic and terrain following 12 sigma levels. The IWM energetics is studied using MM5 model outputs. Prior to this model’s validity and deviation from the corresponding observations (NCEP/NCAR) is assessed. The model’s overestimation/underestimation of wind, temperature and specific humidity at upper troposphere proves that the model has difficulty in picking up corresponding fields at all the model grid points because of terrain complexity over the Himalayas and Tibetan Plateau. Hence, the model fields deviate from the corresponding observations. However, model results match well with the winter global energy budget calculated using reanalysis dataset by Peixoto and Oort (1992). It suggests MM5 model’s fitness in simulating large scale synoptic weather systems. And, thus the model outputs are used for calculation of energetics associated with IWM. It is observed that beyond \(15^{{\circ }}\hbox {N}\) lower as well as upper level convergence of diabatic heating, which represents continental cooling and sinking of heat from atmosphere to land mass (i.e., surface is cooler than surrounding atmosphere) dominates. The diabatic heating divergence (cooling of continents) is found over ocean/sea and whole of the China region, Tibetan and central Himalayas (because of excess condensation than evaporation). The adiabatic generation of kinetic energy depends on the cross isobaric flow (north to south in winter, i.e., the present study shows strong circulation during IWM). It is found that wind divergence of model concludes lower level convergence over study region (i.e., strong winter circulation in the model fields). 相似文献
18.
The hybrid two-way coupled 3DEnsVar assimilation system was tested with the NCMRWF global data assimilation forecasting system. At present, this system consists of T574L64 deterministic model and the grid-point statistical interpolation analysis scheme. In this experiment, the analysis system is modified with a two-way coupling with an 80 member Ensemble Kalman Filter of T254L64 resolution and runs are carried out in parallel to the operational system for the Indian summer monsoon season (June–September) for the year 2015 to study its impact. Both the assimilation systems are based on NCEP GFS system. It is found that hybrid assimilation marginally improved the quality of the forecasts of all variables over the deterministic 3D Var system, in terms of statistical skill scores and also in terms of circulation features. The impact of the hybrid system in prediction of extreme rainfall and cyclone track is discussed. 相似文献
19.
The impact of different land-surface parameterisation schemes for the simulation of monsoon circulation during a normal monsoon
year over India has been analysed. For this purpose, three land-surface parameterisation schemes, the NoaH, the Multi-layer
soil model and the Pleim-Xiu were tested using the latest version of the regional model (MM5) of the Pennsylvania State University
(PSU)/National Center for Atmospheric Research (NCAR) over the Indian summer monsoon region. With respect to different land-surface
parameterisation schemes, latent and sensible heat fluxes and rainfall were estimated over the Indian region. The sensitivity
of some monsoon features, such as Somali jet, tropical easterly jet and mean sea level pressure, is discussed. Although some
features of the Indian summer monsoon, such as wind and mean sea level pressure, were fairly well-simulated by all three schemes,
many differences were seen in the simulation of the typical characteristics of the Indian summer monsoon. It was noticed from
the results that the features of the Indian summer monsoon, such as strength of the low-level westerly jet, the cross-equatorial
flow and the tropical easterly jet were better simulated by NoaH compared with verification analysis than other land-surface
schemes. It was also observed that the distribution of precipitation over India during the peak period of monsoon (July) was
better represented with the use of the NoaH scheme than by other schemes.
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| U. C. MohantyEmail: |
20.
An extreme heat wave hit Egypt in summer 2015. Abnormal hot weather conditions existed over Egypt for the entire summer season. The present paper investigates the relationship between the intertropical convergence zone (ITCZ) over Africa and a scorching heat wave that existed over Egypt in summer 2015. The National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data of mean surface air temperature for the domain of Egypt for the summer season from 1948 to 2015 were used in this study. In addition, data of the daily maximum and daily minimum temperature used for the summer season of the year 2015 were also used. Time cross-section analysis of the daily operational data of geopotential height at level 500 hPa over Egypt from 1 June to 31 August 2015 was done. Moreover, the African ITCZ, both the western and the eastern ITCZ, data for summer of 2015 were used for the said period. The time series, time cross-section, anomaly, and correlation coefficient techniques were used to analyze the datasets. The results revealed that a new climate change record of heat wave over Egypt existed in summer 2015. Moreover, there is an outstanding significant positive correlation between the abrupt shift of African ITCZ position and heat wave occurrence over Egypt in summer 2015. In particular, the southerly movement of the eastern African ITCZ controls the weather over Egypt and led to the extreme heat wave in summer 2015. 相似文献