Near the Atacama Desert, Tacna city in Peru is among the largest arid cities with constant urban development, thus understanding of the urban surface thermal pattern is needed. We propose a comprehensive study of the urban heat island phenomenon, with the objective of (1) determining the spatial and temporal variations of the urban heat islands (UHIs), in the period 1985 to 2020; (2) analyzing the relationship between the UHI and influencing factors such as vegetation, urban area, and population, using indices calculated with satellite images. The Google Earth Engine repository was used to evaluate the corrected images from the years 1985 to 2020. The coincidence between the normalized difference vegetation index (NDVI) and normalized difference built-up index (NDBI) was good, negative between NDVI and the land surface temperature (LST), attributable to dense vegetation, and negative and very high (−0.81) between NDBI and NDVI, as massive urbanization leads to the reduction in the vegetal surface. The NDBI has a high impact on the LST; a coefficient of connections is recorded as 0.46. Tacna is a very arid region, and an increase in the time of the LST occurred with the increase in industrialization and urbanization. The land use/cover change (LUCC) evidences change in the climate in the city of Tacna; temperatures of 24.2 °C to 44.2 °C are observed in the built-up areas. In vegetated areas, the temperature remains below 24 °C, which is associated with a high rate of potential evapotranspiration. Thus, this study shows that variations in urban form and growth have produced the development of intraurban surface thermal patterns.
Groundwater constitutes one of the main sources used to satisfy the water demands of the different users located in a basin. Current groundwater pumping rates in many cases exceed natural recharge, resulting in the overexploitation of aquifers and the deterioration of water quality. Consequently, many aquifer systems in the world have applied and adapted policies to manage the use of groundwater. In this article, we investigate the impacts of groundwater management policies on the Caplina aquifer located in the Atacama Desert, Peru. To evaluate these impacts, we review policies and regulations implemented during the last 40 years. Likewise, more than 25 scientific investigations that were carried out in this aquifer are reviewed and analyzed to understand its hydrodynamics and hydrochemistry, as well as the impact of climate change, among other aspects. The results, based on scientific evidence, show that the current and future conditions of the groundwater of the Caplina aquifer are not sustainable, and likewise, public policies are not effective for reversing this situation. This leads the aquifer system to a situation in which there is a quality degradation of the water, to a point that may be irreversible.
In recent decades, Latin America (LA) has been frequently and severely affected by floods and landslides. There is an urgency for adopting Comprehensive Disaster and Climate Risk Management (CRM). In 2016, a group of Peruvian universities established a network (Gestión Integral del Riesgo de Desastres y Adaptación al Cambio Climático (GIRD-ACC)) committed to the principles of CRM. This article compiles and evaluates the network results/plans and actions. A qualitative study and a methodological strategy are reported featuring: a bibliographic/network documentary review; an account of the events that led to the start and development of the network; and a case study of a three-university network. Results show that the network can help in deepening knowledge and forging a culture of risk prevention. This is by incorporating risk management and climate change awareness in professional training and intensive activity to meet the UN Sustainable Development Goals (SDGs -11, 13, and 17). Results indicate the importance of gaining consensus (a notoriously difficult task in LA) between the authorities and the operational departments; the role of universities’ social responsibilities; incorporating sustainability and risk management themes in the mainstream curricula; and developing a network by learning from similar groupings across LA to improve CRM within universities.
Land surface temperature (LST) and its relationship with vegetation indices (VIs) have proven to be effective for monitoring water stress in large-scale crops. Therefore, the objective of this study is to find an appropriate VI to analyse the spatio-temporal evolution of olive water stress using LST images and VIs derived from Landsat 5 and 8 satellites in the semi-arid region of southern Peru. For this purpose, VIs (Normalised Difference Vegetation Index (NDVI), Enhanced Vegetation Index 2 (EVI2) and Soil Adjusted Vegetation Index (SAVI)) and LST were calculated. The information was processed in Google Earth Engine (GEE) for the period 1985 to 2024, with an interval of every five years for the summer season. The triangle method was applied based on the LST-VIs scatterplot analysis, a tool that establishes wet and dry boundary conditions for the Temperature Vegetation Dryness Index (TVDI). The results indicated a better appreciation of olive orchard water stress over time, with an average of 39% drought (TVDINDVI and TVDISAVI), 24% severe drought (TVDINDVI) and 25% (TVDISAVI) of the total area, compared to TVDIEVI2, which showed 37% drought and 16% severe drought. It is concluded that TVDINDVI and TVDISAVI provide a better visualisation of the water stress map of the olive crop and offer a range of options to address current and future problems in water resource management in the olive sector in semi-arid areas of southern Peru.
The conservation and monitoring of land cover represent crucial elements for sustainable regional development, especially in fragile high Andean ecosystems. This study evaluates the spatiotemporal changes in land use and land cover (LULC) in the Locumba basin over the period of 1984–2023. A hybrid modeling approach combining artificial neural networks (ANN) and cellular automata (CA) was employed to project future changes for 2033, 2043, and 2053. The results reveal a significant reduction in glaciers and lagoons throughout the Locumba basin, with notable declines from 1984 to 2023, while vegetated areas, particularly grasslands and wetlands, experienced substantial expansion. Specifically, grasslands increased by 273.7% relative to their initial coverage, growing from 57.87 km2 in 1984 to over 220.31 km2 in 2023, with projections indicating continued growth to over 331.62 km2 by 2053. This multitemporal analysis provides crucial information for anticipating future land dynamics and underscores the urgent need for strategic conservation planning to mitigate the continued loss of strategic ecosystems in the high Andean region of Tacna.
Glacial retreat is a major global challenge, particularly in arid and semi-arid regions where glaciers serve as critical water sources. This research focuses on glacial retreat and its impact on land cover and land use changes (LULC) in the Barroso Mountain range, Tacna, Peru, which is a critical area for water resources in the hyperarid Atacama Desert. Employing advanced remote sensing techniques through the Google Earth Engine (GEE) cloud computing platform, we analyzed historical trends (1985–2022) using Landsat satellite imagery. A normalized index classification was carried out to generate LULC maps for the years 1986, 2001, 2012, and 2022. Future projections until 2042 were developed using Cellular Automata–Markov (CA–Markov) modeling in QGIS, incorporating six predictive environmental variables. The resulting maps presented an overall accuracy (OA) greater than 83%. Historical analysis revealed a dramatic glacier reduction from 44.7 km2 in 1986 to 7.4 km2 in 2022. In contrast, wetlands expanded substantially from 5.70 km2 to 12.14 km2, indicating ecosystem shifts potentially driven by glacier meltwater availability. CA–Markov chain modeling projected further glacier loss to 3.07 km2 by 2042, while wetlands are expected to expand to 18.8 km2 and bodies of water will reach 4.63 km2. These future projections (with accuracies above 84%) underline urgent implications for water management, environmental sustainability, and climate adaptation strategies, particularly with regard to downstream hydrological risks and ecosystem resilience.