Vol. 130, No. 3 * Pages 225–342 * July - September 2026

Micrometeorological studies of a bridge and the urban area of Hong Kong under south to southwesterly winds associated with tropical cyclone Wutip in June 2025 were conducted using computational fluid dynamic simulation driven by a mesoscale model.  For mean winds, such as 1-min or 10-min averages (as in the application to road traffic management on a bridge), the use of mesoscale meteorological models alone may be sufficient to capture the general wind trend, since the RMSEs of the mean wind speeds were comparable and mostly in the range of 1–5 m s⁻¹. However, if fluctuations in winds are considered and turbulence intensity is a concern for operation (such as the operation of drones in low-altitude economic activities), the coupling of mesoscale meteorological models with computational fluid dynamics models must be considered.  However, the measured turbulence intensity could be rather high (40–50% for turbulence intensity), which may not be achieved with mesoscale coupled computational fluid dynamic models. Numerous issues remain to be resolved for this type of micro-meteorological studies, especially for studies and applications in urban meteorology. Future directions for these studies are also discussed.

The phenomenon of climate aridization is becoming increasingly prominent in both scientific and popular discourses. A plethora of studies have been conducted on this subject, including studies covering the Pannonian Plain; however, comparatively fewer have focused on its eastern region. The present article aims to address this knowledge gap by exploring the potential for aridization at the local scale. We are aware that only by analyzing the evolution of the De Martonne Aridity Index it may not be possible to draw final irrevocable conclusions about the aridization of the climate in the study area, but we believe that it may be a start in this direction. The present study was conducted using data from eight meteorological stations, four from Romania and two each from Hungary and Serbia, for the 1951–2020 time period, and data from three meteorological stations, two from Hungary and one from Romania, for the 1901–2020 time period. The evolution trends of the De Martonne Aridity Index and its component parameters (temperature and precipitation) were analyzed with the help of the non-parametric Mann-Kendall test.

Mountainous regions such as Uttarakhand, India, are highly vulnerable to climate change owing to their complex terrain and dependence on climate-sensitive agriculture. This study analyzes spatiotemporal variability of rainfall and agricultural droughts across Kumaon and Garhwal using historical records (1901–2022) and climate projections (2023–2100) under SSP2-4.5 and SSP5-8.5  moderate and high green-house gas emissions scenarios. Results reveal substantial intra-regional disparities: annual rainfall historically ranged from 1203 mm in rain-shadow zones (Almora, Tehri) to 1930 mm in Himalayan-facing districts (Pithoragarh, Chamoli). Projections suggest up to 20% rainfall increase in Pithoragarh and Chamoli, with little change in Almora and Tehri. Drought analysis shows late-season droughts in the historically dominant agricultural monsoon period Karif (spanning from June to October), particularly in Udham Singh (US) Nagar and Chamoli. Future projections indicate declining severe but more persistent moderate Kharif droughts (e.g., US Nagar 20.9%, Champawat 19%). Conversely, Rabi season (spanning from October to March) droughts are projected to intensify in high-altitude districts: Pithoragarh (20 years, ~11.5 weeks), Dehradun (16 years, ~13.5 weeks), threatening wheat and mustard yields with >40–50% losses. Late-season droughts also remain recurrent in Nainital (26 years) and Uttarkashi (27 years). Overall, Kumaon’s vulnerability stems from persistent Kharif droughts, while Garhwal faces prolonged Rabi droughts (up to 14 weeks). These findings highlight the need for district- and season-specific adaptation strategies, focusing on climate-resilient crops and improved water management.

Range-height indicator (RHI) scans from the Doppler Light Detection And Ranging (LIDAR) systems at the Hong Kong International Airport (HKIA) reveal vortices associated with Kelvin-Helmholtz (KH) instability, jump-like features and mountain waves associated with lower kills and a gap on Lantau Island nearby HKIA. These novel features of terrain-disrupted airflow at HKIA that has not been documented before. This paper analyzes such flow features by considering some parameters of the airflow based on the upper air sounding in Hong Kong, such as Richardson number, Scorer parameter, and Froude number. An attempt has also been made to simulate these novel flow phenomena at HKIA using a high resolution mesoscale numerical weather prediction (NWP) model. The modeling results are found to be a mixed success. Some features, such as mountain waves and jump-like feature, are readily reproduced. However, vortices associated with KH instability are difficult to reproduce, and the vortex shedding simulation does not fully reproduce the observational data based on the Doppler LIDARs. The results in this paper are considered to be useful for the study of mountain meteorology in Hong Kong and elsewhere in the world.

The simultaneous assessment of evapotranspiration and drought is imperative for adaptive water resource planning due to the growing challenges posed by climate change on agricultural production. A downscaling exercise was carried out using the SDSM model for three climate scenarios developed as part of the Sixth Assessment Report (CMIP6): an optimistic scenario (SSP126), a moderate scenario (SSP245), and a pessimistic scenario (SSP585). For model calibration and validation, long-term meteorological data from five stations were used, and drought conditions were assessed using the standardized precipitation index (SPI). Based on the validation results, the model demonstrated high accuracy for simulating temperature and reference evapotranspiration. However, precipitation simulations demonstrated moderate accuracy. Under all scenarios, annual temperatures increased, with the largest increase projected under SSP585. In spite of the fact that changes in precipitation did not reach statistical significance, it is likely that a moderate decline will occur by 2062, under SSP126. Under future climate conditions, there will be a decrease in precipitation in the southeast of the province, an intensified warming in Buin-Zahra, and an increase in evapotranspiration. It was noted that there were frequent severe droughts over the past years. Based on projections for the next decade, drought and wet periods are expected to alternate, with adverse effects expected in the southeast and Buin-Zahra regions. It is evident, from these findings, that sustainable water resource management, climate-adapted agricultural methods, and spatially targeted planning are urgently required to reduce the vulnerability of the province of Qazvin. Hence, adaptation policies should prioritise highly vulnerable areas based on the presented spatial analysis in order to enhance agricultural resilience to drought and climate change.