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Urban Population growth coupled with human activities are the main drivers inducing land use and land cover changes (LU/LCC), which impact earth’s landscapes dynamics. In the era of global challenges, a comprehensive modelling of past and future prediction of LU/LCC is therefore essential. In this regard, the current study aims to model LU/LCC and predict its changes by 2030, 2050 and 2100. Moreover, determine the main driver of these changes, and assess the impact of urbanization on natural ecosystems. For doing so, a three-decade times series (1992–2020) data have been used, including LU/LC, environmental, societal, and auxiliary data to conduct a statistical analysis and modelling using hybrid Multi-Layer-Perceptron Markov-Chain model (MLP-MC). The analyses results showed that urbanization has significantly increased between 1992 and 2020, mainly in the outskirts of the Casablanca metropolis, where economic dynamic, population growth, and territorial infrastructure takes place. This increase was at the expense of barren and agricultural land. Concerning the future projection, the MLP-MC model showed satisfactory results with an overall accuracy (OA) and Cohen’s Kappa greater than 0.98 Revealing that the model has batter reliability to predict LU/LC maps that are identical to observed ones. Consequently, the Future projection indicates that urban areas will persistently sprawl, especially in satellite cities of the economic capital which adversely affect biodiversity, local climate, water, and public health. These findings remain so promising that can guide decision-making and stakeholders to improve sustainable territorial and urban development.

Morocco is encountering record daily maximum temperatures, severe rainfall deficits, intense thunderstorms, droughts, and powerful wind gusts, causing significant harm to people and property. Therefore, it is crucial to understand the course of these occurrences and to determine to what extent the global climate models (GCMs) used to project climate can replicate rainfall before they can be used in downscaling or impact assessment studies. GCMs are essential tools for climate studies, but selecting the best-performing ones remains challenging. This study aims to assess the extent to which certain climate models from the Coupled Model Intercomparison Project’s 6th phase (CMIP6) reproduce the spatial and temporal variability of precipitation across Morocco between 1981 and 2014. Total monthly precipitation from the Climate Hazards Group Infrared Precipitation with Station data (CHIRPS) were used as observational references. We used six robust statistical metrics on monthly and annual scales, including relative bias, correlation coefficient, root means square error, relative error, Taylor diagram, and Kling–Gupta efficiency. The outcomes demonstrated that the ability of GCMs to simulate precipitation varied over space and time. The spatio-temporal properties of precipitation were well reproduced by all GCMs, with correlation values ranging from 0.78 to 0.87. The research also revealed that only a few models accurately captured the spatial patterns of the detected trends. According to the KGE metric, the GCM INM_CM5_0 is ranked first among the models with the highest KGE value (0.45), followed by GCM FGOALS_f3_L with a value of around 0.41. The study results can be applied to climate projections using CMIP6 under different IPCC scenarios.

AbstractUrban ecosystems interact with surroundings via land cover changes and their subsequent impact on surface temperature. In emerging countries, large urban agglomerations often form around cities, and only a few studies have evaluated their impact. This study carries out the first ever large-scale assessment of urban heat island (UHI) and reflects on its mitigation in Morocco. The analysis reveals a well-defined UHI in urban areas built within vegetated lands and an urban heat sink (UHS) in urban areas built within arid regions. Both UHI and UHS amplitudes are higher during day than nighttime, emphasizing vegetation physiological activity. This study shows a monotonic increase in UHI amplitude with urban area size. However, unlike previous studies, this analysis shows that, as urban areas built in desert-like environments grow in size, the UHS gradually decreases to ultimately turn into an UHI. On average, cities built within vegetation are warmer than the rural fringe by 1.51 °C during daytime. This suggests that daytime urban heating may exacerbate the potential climate warming. These results also suggest that adapted trees constitute a natural cooling mechanism and should be part of urban heating mitigation in Morocco.

ABSTRACTWe simulate the impact of impervious surface areas (ISA) on the U.S. local and regional climate. At a local scale, we find the urban area warmer than the surrounding vegetation in most cities, except in arid climate cities where urban temperature is cooler for much of the daytime. For all 9 regions studied, simulated results show that the growing season maximum surface temperature difference between urban and the dominant vegetation occurs around mid-day and is strongest in the northern regions. Regional temperature differences of 3.0°C, 3.4°C, and 3.9°C were simulated in the Northeast, Midwest, and Northwest, respectively. In these regions evaporative cooling, during the growing season, creates a stronger urban heat island (UHI). The UHI is less pronounced during winter when vegetation is dormant. Our results suggest that the ISA temperature is set by building materials' characteristics and its departure from that of the surrounding vegetation is essentially driven by evaporative cooling. Except when rainfall is small, the highest surface runoff to precipitation ratios are simulated in most cities, especially when precipitation events occur as heavy downpours. In terms of photosynthesis, we provide a detailed distribution of maximum production in the U.S., a needed product for policy and urban planners.

AbstractWe combine Landsat and MODIS data in the simple biosphere model to assess the impact of urbanization on surface climate in Marrakech, circa 2010.We find the growing season surface temperature differences between urban and other cover types to vary between 1.6°C and 6.0°C at 1:00 p.m., and between 0.7°C and 1.1°C at 5:00 a.m., local time. Annually however, the built-up area warmed the city 0.3°C during daytime and 0.1°C at night compared to a simulated preurban situation in which the area was fully vegetated. A complete urbanization of the area would decrease its carbon uptake by 0.13 tons and increase its daytime surface temperature by 1.3°C, with 5.72% increase in energy consumption. However, in a “smart” urban growth scenario, we assume the build-up to cover 50% of the area, allowing it to occur first on bare lands, and then we convert all remaining bare lands to orchards; this would counterbalance 60% of daytime warming and sequester 31% more carbon, compared to the actual situation.We find irrigated golf courses to be the most water-consuming covers types, requiring 15 times the region's summer rainfall, and urban areas to distribute 43.8% of incoming precipitation as surface runoff versus only 16.74% for all other cover types combined. This can be a predictor for flash floods.

AbstractWe combine Landsat-and the moderate-resolution imaging spectroradiometer (MODIS)-based products in the Simple Biosphere model (SiB2) to assess the effects of urbanized land on the continental United States (CONUS) surface climate. Using National Land Cover Database (NLCD) impervious surface area (ISA), we define more than 300 urban settlements and their surrounding suburban and rural areas over the CONUS. The SiB2 modeled gross primary production (GPP) over the CONUS of 7.12 PgC (1 PgC = 1015g of carbon) is comparable to the MODIS improved GPP of 6.29 PgC. At state level, SiB2 GPP is highly correlated with MODIS GPP, with a correlation coefficient of 0.94. An increasing horizontal GPP gradient is shown from the urban out to the rural area, with, on average, rural areas fixing 30% more GPP than urbans. Cities built in forested biomes have stronger urban heat island (UHI) magnitude than those built in short vegetation with low biomass. Mediterranean climate cities have a stronger UHI in wet season than in dry season. Our results also show that for urban areas built within forests, 39% of the precipitation is discharged as surface runoff during summer versus 23% in rural areas.

Abstract. The National Land Cover Database (NLCD) Impervious Surface Area (ISA) and MODIS Land Surface Temperature (LST) are used in a spatial analysis to assess the surface-temperature-based urban heat island's (UHIS) signature on LST amplitude over the continental USA and to make comparisons to local air temperatures. Air-temperature-based UHIs (UHIA), calculated using the Global Historical Climatology Network (GHCN) daily air temperatures, are compared with UHISfor urban areas in different biomes during different seasons. NLCD ISA is used to define urban and rural temperatures and to stratify the sampling for LST and air temperatures.We find that the MODIS LST agrees well with observed air temperature during the nighttime, but tends to overestimate it during the daytime, especially during summer and in nonforested areas. The minimum air temperature analyses show that UHIs in forests have an average UHIAof 1°C during the summer. The UHIS, calculated from nighttime LST, has similar magnitude of 1–2°C. By contrast, the LSTs show a midday summer UHISof 3–4°C for cities in forests, whereas the average summer UHIAcalculated from maximum air temperature is close to 0°C. In addition, the LSTs and air temperatures difference between 2006 and 2011 are in agreement, albeit with different magnitude.Résumé. L’Aire des Surfaces impérvieuses (ISA) de la banque Nationale de données sur les Couvertures du Sol (NLCD) et les températures de surface de MODIS (LST) des années 2006 et 2011 sont utilisées dans une analyse spatiale pour évaluer la signature des ilots de chaleur Urbains, basés sur la température de surface (UHIS), sur l’amplitude de la LST aux EUA, et faire des comparaisons avec les températures de l’air locales. Les ilots de chaleur basés sur la température de l’air (UHIA) calculés à partir des données journalières de température obtenues du Network Historique Climatologique Global (GHCN) sont comparés aux UHISpour des arrangements urbains dans des biomes de végétation et des saisons différentes. Les aires impérvieuses (ISA) sont utilisées pour définir les zones urbaines et rurales ainsi que pour stratifier l’échantillonnage des LSTs et des températures de l’air des stations.On trouve que la LST de MODIS est en bon agrément avec la température de l’air durant la nuit, mais tend à la surestimer durant le jour, spécialement pendant l’été et dans les régions non-boisées. L’analyse des températures minimum montre que les peuplements urbains construits en milieu forestier ont une UHIAmoyenne d’environ 1°C durant l’été. Les LSTs nocturnes ont des amplitudes similaires de 1–2°C. Par contraste, les LSTs de MODIS montrent des UHISde 3–4°C dans les centres urbains en milieux forestiers alors que la valeur moyenne d’été des UHIAobtenue à partir des températures maximales avoisine 0°C. Les différences entre les LSTs et la température de l’air entre 2006 et 2011, sont en agreement quoiqu’avec des intensités différentes.

Impervious surface area (ISA) from the National Land Cover Database 2001 and land surface skin temperature from MODIS averaged over three annual cycles (2003–2005) are used in a spatial analysis to assess the surface urban heat island (UHI) signature and its relationship to settlement size and shape, development intensity distribution, and land cover composition for 42 urban settlements embedded in forest biomes in the northeastern United States. Development intensity zones, based on percent ISA, are defined for each urban area emanating outward from the urban core to nearby rural areas and are used to stratify land surface temperature. The stratification is further constrained by biome type and elevation to ensure objective intercomparisons between urban zones within an urban settlement and between settlements. Stratification based on ISA allows the definition of hierarchically ordered urban zones that are consistent across urban settlements and scales. For cities within the northeastern US temperate mixed forest biome, we found that settlement size, shape, and development intensity significantly influenced the amplitude of summer daytime UHI. Our study indicates that for cities of similar size, the ISA density distribution within the urban area and the shape of the urbanized area as measured by area to perimeter ratio are significant modulators of UHI magnitude. Our results indicate that remotely sensed satellite data provide a consistent characterization of the UHI magnitude as well as its major drivers across regional scales.

Impervious surface area (ISA) from the National Geophysical Data Center (NGDC) and land surface temperature (LST) from the Moderate Resolution Imaging Spectroradiometer (MODIS) averaged over three annual cycles (2003–2005) are used in a spatial analysis to assess the urban heat island (UHI) signature on LST amplitude and its relationship with development intensity, size, and ecological setting for more than 3000 urban settlements globally. Development intensity zones based on fractional ISA are defined for each urban area emanating outward from the urban core to the nearby nonurban rural areas and used to stratify sampling for LST. Sampling is further constrained by biome type and elevation data to ensure objective intercomparisons between zones and between cities in different biomes. We find that the ecological context and settlement size significantly influence the amplitude of summer daytime UHI. Globally, an average of 3.8 °C UHI is found in cities built in biomes dominated by forests; 1.9 °C UHI in cities embedded in grass-shrubs biomes; and only a weak UHI or sometimes an urban heat sink (UHS) in cities in arid and semi-arid biomes. Overall, the amplitude of the UHI is negatively correlated (R= –0.66) with the difference in vegetation density between urban and rural zones represented by the MODIS normalized difference vegetation index (NDVI). Globally averaged, the daytime UHI amplitude for all settlements is 2.6 °C in summer and 1.4 °C in winter. Globally, the average summer daytime UHI is 4.7 °C for settlements larger than 500 km2compared with 2.5 °C for settlements smaller than 50 km2and larger than 10 km2. The stratification of cities by size indicates that the aggregated amount of ISA is the primary driver of UHI amplitude, with variations between ecological contexts and latitudinal zones. More than 60% of the total LST variance is explained by ISA for urban settlements within forests at mid to high latitudes. This percentage will increase to more than 80% when only settlements in the US are examined.