University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Earth and Atmospheric Sciences, Department Papers in the Earth and Atmospheric Sciences of 2019 Effects of the Sea Breeze Circulation on Soil Temperature Over Kuwait Using in Situ Observations and the ECMWF Model Hussain Alsarraf Matthew V.D. Broeke Hala Aljassar Follow this and additional works at: https://digitalcommons.unl.edu/geosciencefacpub Part of the Earth Sciences Commons This Article is brought to you for free and open access by the Earth and Atmospheric Sciences, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Papers in the Earth and Atmospheric Sciences by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 1874-2823/19 Send Orders for Reprints to [email protected] 29 The Open Atmospheric Science Journal Content list available at: https://openatmosphericsciencejournal.com RESEARCH ARTICLE Effects of the Sea Breeze Circulation on Soil Temperature Over Kuwait Using in Situ Observations and the ECMWF Model Hussain Alsarraf1,*, Matthew V.D. Broeke2 and Hala Aljassar3 1Department of Mathematics and Natural Sciences, American University of Kuwait, Salmiya, Kuwait 2Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, Lincoln, NE 68588, USA 3Department of Physics, Kuwait University, Kuwait City, Kuwait Abstract: Background: The mesoscale circulation over Kuwait is an important influence on changes in surface temperatures and soil temperatures. Introduction: This paper presents two common summertime atmospheric features over Kuwait linking wind circulation to soil temperatures. Methods: In this study, we use the European Centre for Medium-range Weather Forecasts ECMWF reanalysis ERA-Interim dataset to investigate effects of the synoptic scale and mesoscale circulations. Results: The results show that a large-scale pressure gradient in summer typically leads to northerly winds over Kuwait, while a weak synoptic-scale pressure gradient leads to light easterly humid winds from the Persian Gulf, consistent with a mesoscale circulation. Conclusions: The results demonstrate the significance of wind circulations in driving the Soil Temperature (SOILT). Using the Era-Interim/Land reanalysis dataset for August 2015 over Kuwait, the average SOILT on days of sea breeze is higher than the average SOILT on days dominated by a synoptic- scale pressure gradient. Keywords: Synoptic scale forcing, Mesoscale circulation, Kuwait, Arabian Peninsula, Soil temperature, Shamal, ECWMF, AWOS, ERA-Interim. Article History Received: March 15, 2019 Revised: July 08, 2019 Accepted: July 19, 2019 1. INTRODUCTION changes in summertime SOILT over Kuwait as influenced by variations in the regional mesoscale circulation. Fig. (1) is Atmosphere-land interactions control the soil thermo- provided to familiarize the reader with the topography of the dynamic properties, including interactions between soil region and the locations of cities in Kuwait referenced temperature (SOILT), skin temperature, and air temperature. throughout this paper. The SOILT in the region is affected by various factors including global and regional weather patterns, soil type, and The land-sea temperature contrast is one of the most important factors allowing development of the sea breeze. topography. Normally, precipitation frequency plays a large Greater magnitude of daytime heating of the land surface will role in controlling soil water in terms of infiltration and result in strengthening sea breeze propagation inland [2]. The percolation processes [1]. In this study, we will address the sea breeze relies on a surface temperature difference, * topography, wave propagation, stability, and the background Address correspondence to this author at the Department of Mathematics and Natural Sciences American University of kuwait Salmiya, Kuwait; Tel:+996 synopticscale wind [3]. The summer season in the Arabian 99663313; E-mails: [email protected] and [email protected] Peninsula is defined by many factors such as high diurnal DOI: 10.2174/1874282301913010029, 2019, 13, 29-42 30 The Open Atmospheric Science Journal, 2019, Volume 13 Alsarraf et al. Fig. (1). Kuwait map, (a) Abraque Alhabari (29.3703, 46.9686). (b) Jal Aliyaah (29.6124, 47.5767), (c) Managish (29.0670, 47.539), (d) Wafra (28.5930, 48.1049), (e) Abdaly (30.0235, 47.7046), (f) Rabyah (29.295, 47.9331), (g) Sulaibiya (29.2856, 47.8180). temperature variation and hazy weather. The development of a for temperature, wind speed, precipitation, downward local thermal low pressure system over southern Iran depends shortwave radiation, net surface radiation, and latent and on the increase in solar heating during summer, resulting in sensible heat fluxes has been done in multiple prior studies [7]. northwesterly winds across Kuwait and the Arabian Gulf. Several studies have evaluated and compared the reanalysis These hot and dusty winds, which prevail through most of June from different regions [8 - 10]. and July, are known as Shamal winds. These winds can persist The Shamal wind is supported by the presence of a large- -1 for 2-5 consecutive days at a speed of 10-15 m s [4]. scale pressure gradient [11]. The occasional breakdown of this The strong pressure gradient in the region normally causes pressure distribution results in a sea breeze circulation formed the Shamal wind over the Arabian Peninsula, which results in a near the coast and extending inland. In this study, two case temperature reduction. The strong pressure gradient across the studies will be investigated to illustrate the character of the Arabian Peninsula sometimes weakens during the summertime mesoscale circulation in the region under these distinct resulting in a mesoscale circulation near the coast. Normally, synoptic regimes. Effects on SOILT over Kuwait by this will cause a shift in the wind to become easterly or weakening of the large-scale pressure gradient resulting in a southeasterly during midday due to a sea breeze near the sea breeze will be investigated by comparing days during Kuwait coast which allows moister air to propagate inland, as August 2015 dominated by a mesoscale circulation with days this depends on the strength of the sea breeze during the dominated by a large-scale pressure gradient over Kuwait using daytime [5]. The sea breeze can penetrate several kilometers the ECWMF ERA-Interim/Land reanalysis dataset. inland with average velocities between 2 and 5 m s−1 and can Soil temperature is an important variable for atmospheric develop a vertical structure of up to 2 km in depth [6]. and land emissions, surface radiative emissions, evaporation Monsoon rainfall over the Indian subcontinent is initiated fluxes, soil water phase change, and ecosystem exchange. The SOILT forecasts from ECMWF are also used in Numerical by thermal lows starting in May. When the Indian monsoon is Weather Prediction (NWP), regional climate modeling, the at its peak intensity during mid-summer it extends to the SMOS level2 iterative optimization scheme, and the Soil Mediterranean Sea, resulting in blocking of frontal systems. Moisture Active Passive (SMAP) L-band [12]. A comparing The reduced large-scale pressure gradient associated with the study has been done comparing nearly 700 stations in different monsoon trough favors the formation of mesoscale low environments in the U.S. and Europe with ECMWF forecasts pressure during the last part of summer, also increasing of SOILT during 2012. The results indicate that ECMWF is humidity along the Kuwait coast. Regions far away from the able to predict soil temperature with reasonable accuracy [13, coast will experience low humidity. 14]. The ECWMF reanalysis model for SOILT will provide an Evaluation of the Reanalysis ECMWF (ERA-40) and illustration of the relationship between the mesoscale ECMWF Interim Re-Analysis (ERA-Interim) from ECMWF circulation and soil temperature in the Kuwait desert. Observations and the ECMWF Model The Open Atmospheric Science Journal, 2019, Volume 13 31 Table 1. 'Automatic Weather Observing System (AWOS) stations in Kuwait.' WMO NO. Station Name Height (above mean sea level) Longitude Latitude Type 1 40550 ABDALY 23 m 47° 41'26.747”E 30° 3' 57.467” N Synoptic, Agricultural 2 40573 ABRAQUE AL HABARI 236 m 46° 58' 7.315” E 29° 22'13.735”N Climatic 3 40552 JAL ALIYAH 119 m 47° 34'36.341”E 29° 36'34.561”N Synoptic 4 40580 RABYAH 21 m 46° 58' 7.315” E 29° 22'13.735”N Climatic 5 40587 SULAIBIYA 55 m 47° 43'16.914”E 29° 15'34.856”N Agricultural 6 40592 WAFRA 105 m 48° 3' 35.789” E 28° 33' 23.09” N Synoptic, Agricultural 7 40590 MANAGISH 189 m 47.5333°E 29.0667°N Synoptic Table 2. Variables measured by the agricultural and synoptic AWOS stations. Agricultural AWOS variables Wind Evap Evap LW LW SW SW Net Net Leaf Soil Soil Soil Soil Soil Soil Soil Soil Soil Heat Spd Pan Pen In Out In Out Rad UV-B Wet T 5 T 10 T 20 T 50 T Wet 10 Wet 20 Wet 30 Wet Flux 2M (mm) (mm) (KJ/cm2) (KJ/cm2) (KJ/cm2) (KJ/cm2) (KJ/cm2) (KJ/m2) (%) (°C) (°C) (°C) (°C) 100 (g/cm2) (g/cm2) (g/cm2) 50 (W/m2) (m/s) (°C) (°C) Synoptic and Climatic AWOS variables T (ºC) RH Td T Wind Speed Wind Dir Wind Gust QNH QFF QFE Vis Rain Sun (hr) Cloud (%) (ºC) Grass (ºC) (m/sec) (Deg) (m/sec) (hPa) (hPa) (hPa) (km) (mm) (oct) 2. MATERIALS AND METHODS data were used to force the latest version of the Hydrology- Tiled ECMWF Scheme for Surface Exchanges over Land 2.1. Reanalysis ECWMF ERA-Interim (HTESSEL) land-surface model. HTESSEL includes improved In this study a reanalysis ECWMF model the ERA-Interim soil hydrology [16], a new snow scheme [17, 18], a multi-year is used to investigate two common atmospheric scenarios in the satellite-based vegetation climatology [19, 20], and revised summer by averaging surface temperature and relative bare-soil evaporation [13]. The HTESSEL used SOILT at 5 cm humidity on 17 days with a large-scale pressure gradient and depth on days with a sea breeze and days dominated by a large 11 days dominated by a mesoscale circulation in August 2015.