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The Land surface Interactions with the Atmosphere over the Iberian Semi‐arid Environment (LIAISE) campaign was conducted in July 2021, primarily to investigate the role of irrigation in modulating the boundary‐layer evolution in the Catalan region of northeastern Spain. Contrasts in near‐surface meteorological parameters and boundary‐layer thermodynamic profiles at an irrigated and rainfed (arid) site were established during the morning transition. Evapotranspriation dominated the flux partitioning at the irrigated site (Bowen ratio of 0.07–1.1), whilst sensible heat flux dominated at the rainfed (arid) site (Bowen ratio greater than 10.0). The cumulative evapotranspiration during July 2021 was a factor of 10 greater at the irrigated site than at the rainfed (arid) site. The presence of irrigation was shown to modulate the vertical gradients of turbulence, temperature, and moisture. Irrigation is shown to have a significant effect on the development of the boundary layer, including during the morning transition. The morning transition mean buoyancy flux was 2.8 times smaller at the irrigated site (1.1 m2·$$ {}^2\cdotp $$s−2$$ {}^{-2} $$) compared with the rainfed (arid) site (3.1 m2·$$ {}^2\cdotp $$s−2$$ {}^{-2} $$), with a resultant delay in the near‐surface buoyancy‐flux crossover time (30–90 min) at the irrigated site. At the start of the morning transition (sunrise), the average screen‐level (50‐m) temperature was −1.2$$ -1.2 $$ K (−1.9$$ -1.9 $$ K) colder at the irrigated site relative to the rainfed (arid) site. The colder temperatures at sunrise at the irrigated site are predominantly the result of a colder boundary‐layer thermodynamic profile from the previous day. At the end of the morning transition (convective onset), temperature differences between the two sites extend through much of the boundary layer and increase in magnitude. The average screen‐level (50‐m) temperature difference was −3.6$$ -3.6 $$ K (−2.4$$ -2.4 $$ K) colder at the irrigated site relative to the rainfed (arid) site. There was considerable day‐to‐day variability in temperature contrasts at a regional level (−2.4$$ -2.4 $$ to −6.0$$ -6.0 $$ K). [ABSTRACT FROM AUTHOR]

A steady-state low-level jet observed in the Stable Atmospheric Boundary Layer Experiment in Spain1998 (SABLES-98) campaign is simulated using a large-eddy simulation model. The radiation is taken into account since its contribution to the budget of the tendency of temperature is as important as the contribution of the turbulence in the surface layer. The resulting regime is a two-layer flow separated by a change of the temperature gradient at the level of maximum speed. The upper part has turbulence originated by shear production extending up to 3 times the height of wind maximum and of the same order of magnitude as in the layer below. The jet nose is seen by the model as a decoupling layer, and the use of passive scalars allows for the inspection of the amount of transport across it, which is very small. The lower layer is very sensitive to the surface boundary conditions, but the principal patterns in the upper layer do not change significantly. The runs are compared to the observations through mean profiles, time series, and probability density functions.

Observations of lifted temperature minimum (LTM) profiles in the nocturnal boundary layer were first reported in 1932. It was defined by the existence of a temperature minimum some centimetres above the ground. During the following decades, several research studies analysed this phenomenon verifying its existence and postulating different hypotheses about its origin. The aim of this work is to study the existence and characteristics of LTM during the evening transition by using observations obtained during the Boundary Layer Late Afternoon and Sunset Turbulence (BLLAST) campaign. Data obtained from two masts instrumented with thermocouples and wind sensors at different heights close to the ground and a mast with radiometers are used to study the role of mechanical turbulence and radiation in LTM development. The study shows that LTM can be detected under calm conditions during the day-night transition, several hours earlier than reported in previous work. These conditions are fulfilled under weak synoptic forcing when the local flow shifts associated with a mountain-plain circulation in relatively complex orography. Under these special conditions, turbulence becomes a crucial parameter in determining the ideal conditions for observing LTM. Additionally, LTM observed profiles are also related to a change in the atmospheric radiative characteristics under calm conditions. [ABSTRACT FROM AUTHOR]

Observations of Lifted Temperature Minimum (LTM) profiles in the nocturnal boundary layer were first reported by Ramdas and Atmanathan (1932). It was defined by the existence of a temperature minimum some centimeters above the ground. During the following decades, several research studies analyzed this phenomenon verifying its existence and postulating different hypothesis about its origin. The aim of this work is to study the existence and characteristics of LTM during the evening transition by using observations obtained during the Boundary Layer Late Afternoon and Sunset Turbulence (BLLAST) campaign. Data obtained from two masts instrumented with thermocouples and wind sensors at different heights close to the ground, and a mast with radiometers are used to study the role of mechanical turbulence and radiation in LTM development. The study shows that LTM profiles can be detected under calm conditions during the day-night transition, several hours earlier than reported in previous work. These conditions are fulfilled under weak synoptic forcing during local flow shifts associated with a mountain-plain circulation in relatively complex orography. Under these special conditions, turbulence becomes a crucial parameter in determining the ideal conditions for observing LTM profiles. Additionally, LTM observed profiles are also related to a change in the atmospheric radiative characteristics under calm conditions. [ABSTRACT FROM AUTHOR]

The article focuses on the study regarding the trends of cold indices in Majorca, Spain using the daily minimum temperatures of Majorca Airport from 1972-2008. It mentions that the study inspected eight other climatological stations in the area and used the least-squares methods and non-parametric Mann-Kendall test to measure the trends and confidence level. Moreover, the study reveals a trend of 0.6° Celsius increase per decade at a 95% confidence level.

A mesoscale simulation for Majorca Island is made using the Méso-NH model for a spring night, under a slack synoptic pressure gradient with weak general winds and clear skies. The circulations over and around the island are driven mostly by the locally generated flows, due to the topography and the land–sea thermal contrast. The verification of mesoscale simulations in clear-sky conditions is difficult, especially if the network of stations is not very dense. The main objective of this work is to try to verify the mesoscale simulation using measurements from automatic weather stations and satellite measurements. The model outputs are compared with the available instrumental data and the representativeness of the stations is discussed. Furthermore, complete two-dimensional comparisons are made between the radiative surface temperatures produced by the model and those processed from the National Oceanic and Atmospheric Administration and Meteosat Second Generation (MSG) satellite sensors. The high temporal resolution of the MSG images also allows comparison of the temporal evolutions of the surface temperature between satellite pixels and model grid cells. The procedure permits assessment of the closeness of the simulation to in situ and remote sensing observations. The results of the comparison show that the model is able to reproduce most of the observed patterns, such as intense local cooling or persistent outflows at the largest basins. [ABSTRACT FROM AUTHOR]

A mesoscale simulation for the island of Majorca, Spain, in the western Mediterranean Sea is used to study the nocturnal system of winds under weak synoptic pressure gradients. A very high vertical resolution is used in the first 500 m above ground level to characterize with large detail the thin circulations close to ground, namely, basin and katabatic flows. It is found that the island, the basin, and the slope scales interact strongly, especially when a quasi-steady state is reached in the second part of the night. A high mountain range creates a high pressure area upwind where local winds can develop. Katabatic flows converge to the valleys where they interact with a cold pool, which is advected slowly to sea by the land–sea night-breeze effect combined with a topographic forcing. The katabatic flows experience small entrainment at the top and have well-defined characteristics. The results are partially confirmed by the observations and some satellite images. [ABSTRACT FROM AUTHOR]

Abstract: The evolution of Numerical Weather Prediction (NWP) activities at the Spanish State Meteorological Agency (AEMET) is reviewed not only for historical reasons but mainly to demonstrate the value added by Limited Area Models to deterministic and probabilistic short range forecasting. This paper highlights the decisive role of international cooperation in the general progress achieved by the NWP area of research. In fact, most of the activities here described have taken place in collaboration with the HIRLAM Consortium. The main milestones of HIRLAM model development are analyzed. Long-term performance assessments of HIRLAM operational runs illustrate the positive trend of forecast quality brought by the different scientific developments. Besides, the evolution of the European Centre for Medium-Range Weather Forecasts (ECMWF) operational forecast skill in South-western Europe is presented. HIRLAM complements the global model forecasts in the short range and adds value especially for some surface parameters. The HARMONIE system is the result of the collaboration between HIRLAM and ALADIN Consortia addressing km scale operational forecasting. Some promising results using this new system are shown and the main ongoing work to improve HARMONIE is outlined. Innovative developments on Regional Ensemble Prediction Systems (SREPS) conducted over the last decade at AEMET – within HIRLAM and in collaboration with several NWP centres – are complementing the probabilistic ECMWF forecasts for the short range. Finally, the main achievements and future prospects of SREPS in the mesoscale are presented. [Copyright &y& Elsevier]

Introduction: Surgical excision with margin of 2 cm is the treatment of choice in malignant cutaneous melanoma when Breslow index is >1 mm. When located on the lower limb, these resections can lead to large defects that require complex reconstruction in order to salvage the limb. The use of propeller-perforator flaps has multiple advantages such as the preservation of adjacent muscles, decrease in morbidity in the donor site, and good aesthetic and functional results. Our objective is to expose our experience and results with the use of propeller-perforator flaps for coverage of this kind of defects. Materials and Methods: Patients with malignant cutaneous melanoma of the lower limb who required reconstruction with a propeller-perforator flap between the years 2015 and 2021 in our plastic surgery department were included in this retrospective research. Demographic, reconstructive, oncologic, and functional data were collected and analyzed. Results: The cohort of 22 patients showed 100% of successful reconstructive outcomes. Only 2 patients experienced distal necrosis of the flap that was resolved with local dressings. Fast recovery and early capacity to walk were achieved in the majority of the patients with an average of 10.1 days until weight-baring walking. The 2-year overall and progression-free survival rates were 86.37% and 81.82%, respectively. Conclusion: The use of propeller perforator flaps for oncological defects coverage in the lower limb location has to be considered as a reliable choice as it takes less surgical time and a faster recovery. It allows limb salvage with an adequate length and functionality, with minimal donor site morbidity and a lower index of complications, contributing to improve patient's quality of life and not delaying other oncological treatments., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© 2022 The Author(s).)