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Droughts can affect forest ecosystems and lead to soil degradation, biodiversity loss, and desertification. Not all regions of Mexico are affected in the same way, as some areas are naturally more prone to drought due to their geographical location. Therefore, the objective of this work was to carry out a spatio-temporal analysis of the occurrence of droughts (severe and extreme) in Mexican forest systems, covering the period 2000–2021, and to study the area covered by these events in Mexican forest systems. This analysis was divided into three stages: the classification of land use and vegetation, spatial mapping and the classification of drought intensity, and an analysis of drought frequency and probability in forest systems. The results show that more than 46% of Mexico’s forest area experienced severe and extreme droughts during the 21-year period studied. Broadleaved forests were most affected by severe and extreme droughts, with a frequency of 6 years. The increasing frequency of droughts poses a major challenge to the resilience of forest ecosystems in Mexico, highlighting the need to implement climate change adaptation and forest management measures to protect the country’s biodiversity and natural resources.

Knowing the spatiotemporal variability of temperature and precipitation, as well as their future projections, is essential to assess environmental risks and plan long-term mitigation and adaptation. In this study, the General Circulation Models (GCMs) HadGEM3-GC31-LL, MRI-ESM2-0 and ACCESS-ESM1-5 of the Coupled Model Intercomparison Project (CMIP6) have been used, under two Shared Socioeconomic Pathways (SPP2-4.5 and SSP5-8.5), to project the minimum and maximum air temperature and the mean annual precipitation in Atlacomulco Rural Development District (ARDD). 30 meteorological stations were used to perform regionalized climate change projections by downscaling using LARS-WG 7. The expected changes were evaluated for three time horizons: near horizon (2021–2040), mid horizon (2041–2060) and far horizon (2061–2080); compared to the historical period (1985–2017). Based on the results, the annual minimum temperature towards the far horizon is projected to increase by 2.0 ºC with SSP2-4.5, and 3.1 ºC with SSP5-8.5; while the annual maximum temperature towards the far horizon is projected to increase between 2.5 ºC with SSP2-4.5 and 3.8 ºC using SSP5-8.5. Precipitation shows an increase for SSP2-4.5 in the near and middle horizons with 15.7 and 42.5 mm.year−1, respectively, while the largest decrease is projected towards the middle horizon of SSP5-8.5 with − 26.3 mm.year−1. The findings of this study provide detailed information on climate change projections in the ARDD and can serve as a useful guide for the management of different ecosystems.

Background information Mexico faces a great challenge in producing, storing, and distributing food to guarantee the food security of its population. Natural disasters, climate change and changes in land cover are dynamic drivers affecting food production. In this study, we propose a method for assessing food security by evaluating the amount of food in Mexico that is available to meet the demand of its population. An indicator of food availability based on environmental, social, production and food supply variables is proposed. Methods Food availability in Mexico's 2471 municipalities was assessed using five sub-indicators covering environmental and social conditions of production, food supply, caloric and protein sufficiency, and food supply. A database of 19 variables was integrated to calculate an index of food availability by municipality. Spatial analysis techniques were used to identify areas with specific needs and to formulate public policy recommendations. Results The availability of food is not a problem at all in 90% of the municipalities in the country. We found that the environmental and social conditions are suitable for producing food from agriculture and livestock and there are sufficient food outlets. The caloric demand and protein requirements of the population can be met in at least 87% of the municipalities. Thus, the environmental and social conditions are good in more than 85% of the municipalities. If food production and availability are sufficient; then, the problem of food insecurity may be due to other causes. Conclusions and recommendations The conclusion is that food insecurity in Mexico is influenced by additional factors. An urgent intervention is needed, including public policies to provide economic support to the most affected segments of the population.

Shrimp farms are within the main aquaculture activities and In the last 30 years, shrimp farms have expanded along the Gulf of California. Because the shrimp farm’s production is related to the pond area and the extended location of shrimp farms, we employed a multi-disciplinary approach to study the process of annual shrimp farm expansion, in addition to predicting shrimp production in the short term. Our study hypothesizes that semi-intensive shrimp farm production is dependent on the pond area which can be accurately quantified by using remote sensing image classification combined with the historical production data of shrimp aquaculture. We could calculate the long-term expansion of the total pond area and forecast the total annual shrimp production in the short-term. Our results highlight the development over the last 28 years. The total surface area of the shrimp ponds grew by more than 1100%. The linear regression model between the shrimp farms area, calculated using remote sensing, and statistical data on shrimp production, was strongly positive and significant (r2 = 0.874, p =2.209e-11). Likewise, the linear regression model for the total pond area as a function of time resulted strong positive and statistically significant (r2 = 0.936, p =2.917e-15). We demonstrated that the shrimp production could be assessed based on the total pond area by year, obtained by remote sensing. We estimated the past long-term shrimp farm expansion in the study zone using remote sensing data. This methodology is valuable for monitoring food security, aquaculture management decisions, and coastal ecology.

The University of Chicago Project on Security and Threats presents the updated and expanded Database on Suicide Attacks (DSAT), which now links to Uppsala Conflict Data Program data on armed conflicts and includes a new dataset measuring the alliance and rivalry relationships among militant groups with connections to suicide attack groups. We assess global trends in suicide attacks over four decades, and demonstrate the value of the expanded DSAT with special attention to the growing diffusion of suicide attacks in armed conflicts and the large role of networks established by Al-Qaeda and the Islamic State through 2019 in this diffusion. Overall, the expanded DSAT demonstrates the advantages of integration across datasets of political violence for expanding research on important outcomes, generating new knowledge about the spread of particularly deadly forms of political violence, and raising important new questions about the efficacy of current policies to curb their spread.

Water erosion is a significant issue that impacts a substantial portion of Mexico. The purpose of this study is to establish a connection between soil erosion and soil organic carbon (SOC) reserves. This work was conducted within a small watershed in the Mixteca Alta region of Oaxaca, in order to examine the correlation between erosion intensity, determined via the revised universal soil loss equation (RUSLE), and SOC storage, calculated using spatial models. The results reveal erosion values between 0.19 and 266.99 Mg ha-1 year-1, with 305 693 t of erosion in the micro-watershed. The erosion patterns are closely linked to land use categories. The average SOC values (​​in Mg ha-1) were associated with erosion, which was reclassified as null (31.79), light (22.36), moderate (16.19), and high (5.22). Kendall's tau coefficient showed a negative correlation of -0.39 between erosion and SOC. This inverse relationship can be attributed to the influence of erosive processes on the transport and exposure of SOC, the later replacement of carbon in the vegetation, and a reduced decomposition in deposition areas. Therefore, conservation practices, particularly terracing, have the potential to improve carbon storage. La erosión hídrica es un problema significativo que afecta gran parte de México. El propósito de este estudio es establecer una conexión entre la erosión del suelo y las reservas de carbono orgánico del suelo (COS). Este trabajo fue realizado dentro de una pequeña cuenca hidrográfica en la región Mixteca Alta de Oaxaca para evaluar la correlación entre la intensidad de la erosión, determinada a través de la   ecuación universal de pérdida de suelo revisada (RUSLE), y el almacenamiento del COS, calculado mediante modelado espacial. Los resultados revelan valores de erosión entre 0.19 y 266. 99 Mg ha-1 año-1, con una erosión total de 305 693 t en la microcuenca. Los patrones de erosión están estrechamente vinculados a las categorías de uso del suelo. Los valores promedio de COS (en Mg ha-1) se asociaron a la erosión, reclasificada como nula (31.79), ligera (22.36), moderada (16.19) y alta (5.22). El coeficiente tau de Kendall mostró una correlación negativa de -0.39 entre la erosión y el COS.  Esta relación inversa puede atribuirse a la influencia de los procesos de erosión en el transporte y la exposición del COS, el posterior reemplazo de carbono de la vegetación y la reducción de la descomposición en las áreas de depósito. Por lo tanto, las prácticas de conservación, en particular las terrazas, tienen potencial para mejorar el almacenamiento de carbono.

Vulnerability to climate change was evaluated for three different time periods: 1990, 2000, and 2010. Our objective was to discuss the scope of a multi-temporal assessment of vulnerability. The method used 55 indicators—with emphasis on the agricultural sector in Mexico—of which 27 were updated for the year 2010 and 33 were retrospectively estimated for the year 1990. The results show that in the 20-year study period, the exposure of the municipalities (and inhabitants) has increased, and sensitivity and adaptive capacity have decreased. The number of municipalities vulnerable to climate change declined over the 20-year period. We found that calculating vulnerability by adding exposure and sensitivity and subtracting adaptive capacity (E + S − AC) can lead to unintentional underestimation of total vulnerability. When rating vulnerability, care must be taken in what is reported: the results differ for the number of inhabitants versus the number of municipalities. Our previous published vulnerability evaluation was for the year 2000, so we wanted to evaluate the sensitivity of some variables and the vulnerability formula itself we used in that moment. It is possible to evaluate the vulnerability multi-temporally, which allows to evaluate the sensibility and calibration of the variables and indicators used and the reconsideration of their application.

The slot-die coating process plays an important role in the industry, as it is employed in many different fields. The characteristics of the final application are determined by the flow between the die and the roller. This research paper aims to develop a mathematical model of such flow that takes into account the roller deformations caused by high pressure values reached by the coating fluid. This elastohydrodynamic model is made up of a coupling between the mathematical model of the flow and the mathematical model of the roller deformations. Model resolution is undertaken numerically by deforming the flow domain according to the roller deformations using computational fluid dynamics and computational solid mechanics techniques. For its part, the finite volume method is used to perform the flow model analysis and the finite element method is employed to deal with roller deformations. The results obtained from this model give information on the flow pressure distribution, coating gaps, meniscus position, extent of roller deformations in the coating flow, and the influence of different operating conditions. The information obtained from this study is valuable for industrial applications, as it gives insights into the coating process that can help manufacturers to define a suitable combination of operating parameters in order to obtain coating applications that meet quality and performance requirements. Graphical Abstract Graphical Abstract

Assessing adaptive capacity to climate change is a complex task since it is a multidimensional component. There has been considerable discrepancy between the dimensions or elements that compose it. This study aimed to analyze the relevant dimensions and indicators that allow estimation of the adaptive capacity to climate change and to propose a set of indicators that will enable their application to assessment at the level of agricultural producers. A systematic review of scientific literature on evaluating or measuring adaptive capacity to climate change was carried out. Subsequently, the indicators were analyzed and selected through a coincidence analysis and were calibrated through a multicriteria evaluation with relevant actors in the southern Mexico, state of Chiapas. In total, 329 indicators were identified and analyzed. As a result, 19 indicators were selected and then grouped into six dimensions: economic resources, human resources, infrastructure for production and marketing, institutionality, social capital, and natural resources. These represent the 14 specific dimensions with the greatest potential to contribute to the estimation of adaptive capacity to climate change. The dimensions and indicators can be applied to assess the adaptive capacity of farmers in Mexico at a national or regional scale and specifically by producer types.

Mexico has a wide range of biophysical and socioeconomic conditions that result in farmers with highly diverse traits and activities in relation to their livelihoods. The aim of this research was to identify specific traits of Mexican farmers that would allow them to be classified through a multidimensional approach that includes the risk of production in the face of exposure and vulnerability to climate change. The method included three dimensions: producer sensitivity, production destination, and exposure to climate change. Principal component analysis combined with the Dalenius and Hodges optimal stratification technique was used to stratify the universe of agricultural producers. The results show that up to 227 groups of agricultural producers can be identified in Mexico, and it was possible to classify them into 19 types, ranging from agricultural producers at greatest risk due to the adverse effects of climate change to agricultural producers with fewer difficulties to produce in conditions of climate change. This proposed multidimensional typology of agricultural producers can become an essential input for designing, reorienting, or focusing public policies in the agricultural sector and moving towards fulfilling the commitments declared in the INDC-2030.