Climate Change Hotspot Research Articles

Relating Climate, Drought and Radial Growth in Broadleaf Mediterranean Tree and Shrub Species: A New Approach to Quantify Climate-Growth Relationships

The quantification of climate–growth relationships is a fundamental step in tree-ring sciences. This allows the assessment of functional responses to climate warming, particularly in biodiversity and climate-change hotspots including the Mediterranean Basin. In this region, broadleaf tree and shrub species of pre-Mediterranean, subtropical origin, have to withstand increased aridification trends. However, they have not been widely studied to assess their long-term growth responses to climate and drought. Since these species evolved under less seasonal and wetter conditions than strictly Mediterranean species, we hypothesized that their growth would mainly respond to higher precipitation and water availability from spring to early summer. Here, we quantified climate–growth relationships in five of these broadleaf species showing different leaf phenology and wood type (Pistacia terebinthus L., Pistacia lentiscus L., Arbutus unedo L., Celtis australis L., and Laurus nobilis L.) by using dendrochronology. We calculated Pearson correlations between crossdated, indexed, mean ring width series of each species (chronologies) and monthly climate variables (mean temperature, total precipitation). We also calculated correlations between the species’ chronologies and a drought index on 7-day scales. Lastly, we compared the correlation analyses with “climwin” analyses based on an information-theoretic approach and subjected to cross-validation and randomization tests. As expected, the growth of all species was enhanced in response to wet and cool conditions during spring and early summer. In some species (P. lentiscus, A. unedo, C. australis,) high prior-winter precipitation also enhanced growth. Growth of most species strongly responded to 9-month droughts and the correlations peaked from May to July, except in L. nobilis which showed moderate responses. The “climwin” analyses refined the correlation analyses by (i) showing the higher explanatory power of precipitation (30%) vs. temperature (7%) models, (ii) selecting the most influential climate windows with June as the median month, and (iii) providing significant support to the precipitation model in the case of P. terebinthus confirming that the radial growth of this species is a robust proxy of hydroclimate variability. We argue that “climwin” and similar frameworks based on information-theoretic approaches should be applied by dendroecologists to critically assess and quantify climate–growth relationships in woody plants with dendrochronological potential.

The confounding effect of snow cover on assessing spring phenology from space: A new look at trends on the Tibetan Plateau

The Tibetan Plateau is the highest and largest plateau in the world, hosting unique alpine grassland and having a much higher snow cover than any other region at the same latitude, thus representing a “climate change hot-spot”. Land surface phenology characterizes the timing of vegetation seasonality at the per-pixel level using remote sensing systems. The impact of seasonal snow cover variations on land surface phenology has drawn much attention; however, there is still no consensus on how the remote sensing estimated start of season (SOS) is biased by the presence of preseason snow cover. Here, we analyzed SOS assessments from time series of satellite derived vegetation indices and solar-induced chlorophyll fluorescence (SIF) during 2003–2016 for the Tibetan Plateau. We evaluated satellite-based SOS with field observations and gross primary production (GPP) from eddy covariance for both snow-free and snow covered sites. SOS derived from SIF was highly correlated with field data (R2 = 0.83) and also the normalized difference phenology index (NDPI) performed well for both snow free (R2 = 0.77) and snow covered sites (R2 = 0.73). On the contrary, normalized difference vegetation index (NDVI) correlates only weakly with field data (R2 = 0.35 for snow free and R2 = 0.15 for snow covered sites). We further found that an earlier end of the snow season caused an earlier estimate of SOS for the Tibetan Plateau from NDVI as compared to NDPI. Our research therefore adds new evidence to the ongoing debate supporting the view that the claimed advance in land surface SOS over the Tibetan Plateau is an artifact from snow cover changes. These findings improve our understanding of the impact of snow on land surface phenology in alpine ecosystems, which can further improve remote sensing based land surface phenology assessments in snow-influenced ecosystems.

Understanding climate change over the southwestern Mediterranean using high-resolution simulations

The severe wintertime precipitation decline projected by global climate models (GCMs) over the Southwestern Mediterranean makes this region a major climate change hotspot. Here, we evaluate the performance of the MIT Regional Climate Model (MRCM) in simulating seasonal and inter-annual regional climatic features over Northwestern Africa and the Iberian Peninsula (NWAIP), and develop and interpret regional climate change projections over the same region under the RCP4.5 and 8.5 scenarios, at a resolution of 12 km, driven by three carefully selected GCMs. MRCM succeeds in correctly capturing the spatio-temporal patterns of precipitation when forced by ERA-Interim reanalysis data. In addition to substantial year-round warming, the MRCM ensemble projects a significant decline in precipitation during winter and spring under continued anthropogenic forcing. Even with significant climate change mitigation, the drying is relatively large, with an average of − 34% in precipitation over Morocco’s three main watersheds during spring, and − 22% during winter. Projections for the Iberian Peninsula are less severe, though drying trends are still robust. The consistency of the precipitation projections is discussed in the light of physical mechanisms acting at the regional scale. Being located downwind of a large desert, the region is particularly vulnerable to the changes in circulation projected by global models. The latter will advect dry air from the Sahara, which will suppress precipitation. The local topography also contributes to these trends. Overall, our results elucidate the physical processes responsible for winter and spring drying in the southwestern Mediterranean.

Building an Engaged Himalayan Sustainability Science

The Himalayan region is facing a new crisis under climate change, rapid economic transformation, and escalating geopolitical tensions. A large body of Himalayan sciences has endeavored to understand this challenge but has failed to engage meaningfully with the local people and policymakers. I argue for a new engaged Himalayan sustainability science that not only understands and interprets the emerging challenges but also strengthens societal capability.

Larval energetics of the Sydney rock oyster Saccostrea glomerata and Pacific oyster Magallana gigas

Larvae are a critical dispersal stage of marine invertebrates, and their survival depends on nutrition and energetics. This study compared the size, survival, metabolic rate and egg and larval lipid class profiles of larvae of the endemic Sydney rock oyster Saccostrea glomerata and the invasive Pacific oyster Magallana gigas through a period of starvation for 5 and 9 d after fertilisation. Starved larvae grew without food until 5 d of age, at which point they stopped developing, but resumed growth when fed. Egg lipids profiles comprised 78.1 and 74.5% triacylglycerol for M. gigas and S. glomerata respectively. When fed, larvae of M. gigas were significantly larger in size and had faster growth and similar survival compared to S. glomerata. When starved, larvae of M. gigas and S. glomerata grew at similar rates, and there was a trend for lower survival of M. gigas. Larval endogenous lipid reserves were deleted in the first 24 h. Larvae of M. gigas had more total lipids and comparatively more diacylglycerols, monoacylglycerols, phospholipids and cholesterol, whereas S. glomerata had more diacylglycerols and produced sterol esters. Starvation altered the patterns of lipid assimilation, and metabolic rates of larvae of M. gigas and S. glomerata differed over time. When starved, S. glomerata larvae had greater capacity to cope with starvation compared to M. gigas, perhaps due to an evolutionary history in oligotrophic estuaries. As the climate rapidly changes in this global climate-change hotspot, S. glomerata is likely to be negatively affected.

Factors controlling plankton community production, export flux, and particulate matter stoichiometry in the coastal upwelling system off Peru

Abstract. Eastern boundary upwelling systems (EBUS) are among the most productive marine ecosystems on Earth. The production of organic material is fueled by upwelling of nutrient-rich deep waters and high incident light at the sea surface. However, biotic and abiotic factors can modify surface production and related biogeochemical processes. Determining these factors is important because EBUS are considered hotspots of climate change, and reliable predictions of their future functioning requires understanding of the mechanisms driving the biogeochemical cycles therein. In this field experiment, we used in situ mesocosms as tools to improve our mechanistic understanding of processes controlling organic matter cycling in the coastal Peruvian upwelling system. Eight mesocosms, each with a volume of ∼55 m3, were deployed for 50 d ∼6 km off Callao (12∘ S) during austral summer 2017, coinciding with a coastal El Niño phase. After mesocosm deployment, we collected subsurface waters at two different locations in the regional oxygen minimum zone (OMZ) and injected these into four mesocosms (mixing ratio ≈1.5 : 1 mesocosm: OMZ water). The focus of this paper is on temporal developments of organic matter production, export, and stoichiometry in the individual mesocosms. The mesocosm phytoplankton communities were initially dominated by diatoms but shifted towards a pronounced dominance of the mixotrophic dinoflagellate (Akashiwo sanguinea) when inorganic nitrogen was exhausted in surface layers. The community shift coincided with a short-term increase in production during the A. sanguinea bloom, which left a pronounced imprint on organic matter C : N : P stoichiometry. However, C, N, and P export fluxes did not increase because A. sanguinea persisted in the water column and did not sink out during the experiment. Accordingly, export fluxes during the study were decoupled from surface production and sustained by the remaining plankton community. Overall, biogeochemical pools and fluxes were surprisingly constant for most of the experiment. We explain this constancy by light limitation through self-shading by phytoplankton and by inorganic nitrogen limitation which constrained phytoplankton growth. Thus, gain and loss processes remained balanced and there were few opportunities for blooms, which represents an event where the system becomes unbalanced. Overall, our mesocosm study revealed some key links between ecological and biogeochemical processes for one of the most economically important regions in the oceans.

A concerted research effort to advance the hydrological understanding of tropical páramos

AbstractPáramos, a neotropical alpine grassland‐peatland biome of the northern Andes and Central America, play an essential role in regional and global cycles of water, carbon, and nutrients. They act as water towers, delivering water and ecosystem services from the high mountains down to the Pacific, Caribbean, and Amazon regions. Páramos are also widely recognized as a biodiversity and climate change hot spots, yet they are threatened by anthropogenic activities and environmental changes. Despite their importance for water security and carbon storage, and their vulnerability to human activities, only three decades ago, páramos were severely understudied. Increasing awareness of the need for hydrological evidence to guide sustainable management of páramos prompted action for generating data and for filling long‐standing knowledge gaps. This has led to a remarkably successful increase in scientific knowledge, induced by a strong interaction between the scientific, policy, and (local) management communities. A combination of well‐established and innovative approaches has been applied to data collection, processing, and analysis. In this review, we provide a short overview of the historical development of research and state of knowledge of the hydrometeorology, flux dynamics, anthropogenic impacts, and the influence of extreme events in páramos. We then present emerging technologies for hydrology and water resources research and management applied to páramos. We discuss how converging science and policy efforts have leveraged traditional and new observational techniques to generate an evidence base that can support the sustainable management of páramos. We conclude that this co‐evolution of science and policy was able to successfully cover different spatial and temporal scales. Lastly, we outline future research directions to showcase how sustainable long‐term data collection can foster the responsible conservation of páramos water towers.

Long-Term Analysis of Atmospheric Energetics Components over the Mediterranean, Middle East and North Africa

In this research, one aspect of the climate that is not commonly referred to, namely, the long-term changes in the components of the atmospheric energy, is investigated. In this respect, the changes in four energy forms are considered, namely, Kinetic Energy (KE), Thermal Energy (TE), Internal Energy (IE), Potential Energy (PE) and Latent Energy (LE); the Energy Conversion (EC) between Kinetic Energy and Potential plus Internal Energy (PIE) is also considered. The area considered in this long-term energetics analysis covers the entire Mediterranean basin, the Middle East and a large part of North Africa. This broad geographical area has been identified by many researchers as a hot spot of climate change. Analyses of climatic data have indeed shown that this region has been experiencing marked changes regarding several climatic variables. The present energetics analysis makes use of the ERA-Interim database for the period from 1979 to 2018. In this 40-year period, the long-term changes in the above energetics components are studied. The monthly means of daily means for all the above energy forms and Energy Conversion comprise the basis for the present research. The results are presented in the form of monthly means, annual means and spatial distributions of the energetics components. They show the dominant role of the subtropical jet-stream in the KE regime. During the study period, the tendency is for KE to decrease with time, with this decrease found to be more coherent in the last decade. The tendency for TE is to increase with time, with this increase being more pronounced in the most recent years, with the maximum in the annual mean in KE noted in 2015. The sum of Potential and Internal energies (PIE) and the sum of Potential, Internal and Latent energies (PILE) follow closely the patterns established for TE. In particular, the strong seasonal influence on the monthly means is evident with minima of PIE and PILE noted in winters, whereas, maxima are registered during summers. In addition, both PIE and PILE exhibit a tendency to increase with time in the 40-year period, with this increase being more firmly noted in the more recent years. Although local conversion from KE into PIE is notable, the area averaging of EC shows that the overall conversion is in the direction of increasing the PIE content of the area at the expense of the KE content. EC behaves rather erratically during the study period, with values ranging from 0.5 to 3.7 × 102 W m−2. Averaged over the study area, the Energy Conversion term operates in the direction of converting KE into PIE; it also lacks a seasonal behavior.

Seasonal variability of net sea-air CO2 fluxes in a coastal region of the northern Antarctic Peninsula

We show an annual overview of the sea-air CO2 exchanges and primary drivers in the Gerlache Strait, a hotspot for climate change that is ecologically important in the northern Antarctic Peninsula. In autumn and winter, episodic upwelling events increase the remineralized carbon in the sea surface, leading the region to act as a moderate or strong CO2 source to the atmosphere of up to 40 mmol m–2 day–1. During summer and late spring, photosynthesis decreases the CO2 partial pressure in the surface seawater, enhancing ocean CO2 uptake, which reaches values higher than − 40 mmol m–2 day–1. Thus, autumn/winter CO2 outgassing is nearly balanced by an only 4-month period of intense ocean CO2 ingassing during summer/spring. Hence, the estimated annual net sea-air CO2 flux from 2002 to 2017 was 1.24 ± 4.33 mmol m–2 day–1, opposing the common CO2 sink behaviour observed in other coastal regions around Antarctica. The main drivers of changes in the surface CO2 system in this region were total dissolved inorganic carbon and total alkalinity, revealing dominant influences of both physical and biological processes. These findings demonstrate the importance of Antarctica coastal zones as summer carbon sinks and emphasize the need to better understand local/regional seasonal sensitivity to the net CO2 flux effect on the Southern Ocean carbon cycle, especially considering the impacts caused by climate change.

Compound warm–dry and cold–wet events over the Mediterranean

Abstract. The Mediterranean (MED) Basin is a climate change hotspot that has seen drying and a pronounced increase in heatwaves over the last century. At the same time, it is experiencing increased heavy precipitation during wintertime cold spells. Understanding and quantifying the risks from compound events over the MED is paramount for present and future disaster risk reduction measures. Here, we apply a novel method to study compound events based on dynamical systems theory and analyse compound temperature and precipitation events over the MED from 1979 to 2018. The dynamical systems analysis quantifies the strength of the coupling between different atmospheric variables over the MED. Further, we consider compound warm–dry anomalies in summer and cold–wet anomalies in winter. Our results show that these warm–dry and cold–wet compound days are associated with large values of the temperature–precipitation coupling parameter of the dynamical systems analysis. This indicates that there is a strong interaction between temperature and precipitation during compound events. In winter, we find no significant trend in the coupling between temperature and precipitation. However in summer, we find a significant upward trend which is likely driven by a stronger coupling during warm and dry days. Thermodynamic processes associated with long-term MED warming can best explain the trend, which intensifies compound warm–dry events.

A Warming Mediterranean: 38 Years of Increasing Sea Surface Temperature

The Mediterranean basin has been classified as a hot-spot for climate change. The Mediterranean Sea plays a fundamental regulatory role in the regional climate. We have analyzed the largest available and complete time series (1982–2019) of blended sea surface temperature (SST) data to study its seasonal cycle and look for a possible warming trend in the basin. From the analysis of the Mediterranean mean SST time series, a new temporal seasonal division is derived that differs from the one used in atmospheric climatology. Then, the SST time series were decomposed into their seasonal and trend components, and a consistent warming trend of 0.035 °C/year was obtained. The nature of this trend has been investigated, indicating a higher warming trend for both maximum and high/summer SST values than for the winter/colder ones. This reinforces the consistency of the SST increase since it is not only based on the presence of extreme values, but on a homogeneous basin global increase of high SST records as well. Although warming is found throughout the Mediterranean basin, the spatial variability found leads to the division of the basin into three distinct subareas regarding warming.

Monitoring the resilience of a no-take marine reserve to a range extending species using benthic imagery.

Global climate change is driving the redistribution of marine species and thereby potentially restructuring endemic communities. Understanding how localised conservation measures such as protection from additional human pressures can confer resilience to ecosystems is therefore an important area of research. Here, we examine the resilience of a no-take marine reserve (NTR) to the establishment of urchin barrens habitat. The barrens habitat is created through overgrazing of kelp by an invading urchin species that is expanding its range within a hotspot of rapid climate change. In our study region, a multi-year monitoring program provides a unique time-series of benthic imagery collected by an Autonomous Underwater Vehicle (AUV) within an NTR and nearby reference areas. We use a Bayesian hierarchical spatio-temporal modelling approach to estimate whether the NTR is associated with reduced formation of urchin barrens, and thereby enhances local resilience. Our approach controls for the important environmental covariates of depth and habitat complexity (quantified as rugosity derived from multibeam sonar mapping), as well as spatial and temporal dependence. We find evidence for the NTR conferring resilience with a strong reserve effect that suggests improved resistance to the establishment of barrens. However, we find a concerning and consistent trajectory of increasing barrens cover in both the reference areas and the NTR, with the odds of barrens increasing by approximately 32% per year. Thus, whereas the reserve is demonstrating resilience to the initial establishment of barrens, there is currently no evidence of recovery once barrens are established. We also find that depth and rugosity covariates derived from multibeam mapping provide useful predictors for barrens occurrence. These results have important management implications as they demonstrate: (i) the importance of monitoring programs to inform adaptive management; (ii) that NTRs provide a potential local conservation management tool under climate change impacts, and (iii) that technologies such as AUVs and multibeam mapping can be harnessed to inform regional decision-making. Continuation of the current monitoring program is required to assess whether the NTR can provide long term protection from a phase shift that replaces kelp with urchin barrens.

Urban resilience in climate change hotspot

Past and ongoing research shows that African cities remain one of the vulnerable zones of climate change, yet the least prepared. With an expected increase in climate change impacts coupled with rapid urbanization in African cities, this paper inquires: what if more attention is devoted to urban planning in the efforts towards addressing climate change issues and building resilient urban futures in Africa? Using available and relevant literature and Ghana as a case study, it argues that it is about time African cities begin to address climate change through urban planning. This paper anayzes the unexplored potentials of urban planning in addressing issues of climate change in the continent, and makes recommendations for the engagement of urban planning in developing resilient African cities.

Atlantic‐Pacific Gradients Drive Last Millennium Hydroclimate Variability in Mesoamerica

AbstractThe paleoclimatic record from Mexico and Central America, or Mesoamerica, documents dramatic swings in hydroclimate over the past few millennia. However, the dynamics underlying these past changes remain obscure. We use proxy indicators of hydroclimate to show that last millennium hydroclimate variability was dominated by opposite‐signed moisture anomalies in northern and southern Mesoamerica. This pattern results from changes in moisture convergence driven by Atlantic‐Pacific interbasin temperature gradients. While this pattern is reproduced by several models and multiple experiments with a single model, models appear to disagree about the underlying dynamics of this interbasin gradient. Moreover, disagreement about the interbasin gradient, and associated hydroclimate pattern, dominates spread in 21st century regional hydroclimate projections. These results emphasize the role of interbasin asymmetries in governing past and future regional climate change. They also demonstrate that paleoclimate studies can elucidate mechanisms directly relevant to projecting future hydroclimate in climate change hot spots like Mesoamerica.

The impact of reservoir construction and changes in land use and climate on ecosystem services in a large Mediterranean catchment

The Mediterranean region has been identified as one of the most affected global hot-spots for climate change, which is already manifested by faster increasing temperatures than the global mean and significant decreases in annual precipitation. Besides, over the past decades, important land cover changes have occurred, such as reforestation, agricultural intensification, urban expansion and the construction of many reservoirs. Here we study the impacts of these changes in a typical large Mediterranean catchment and focus on relevant ecosystem services, i.e. primary production, water supply, food production, water regulation, flood and erosion control, and cultural ecosystem services. We applied a hydrological model, coupled with a soil erosion and sediment transport model, for the period 1971–2010 to the entire catchment, and for an extended period (1952–2018), with more pronounced land use changes, to one of its subcatchments that plays a crucial role for regional drinking water provision. Climate change in the evaluated period is characterized by a decrease in precipitation and an increase in temperature. Land use changes included an increase in natural vegetation in the headwaters, agricultural intensification and reservoir construction in the central part, and urban expansion in the downstream part of the catchment. The positive impacts on ecosystem services were quantified by a decrease in hillslope erosion, sediment yield, sediment concentration and flood discharge, which are mainly attributed to climate change and reservoir construction. The negative impacts were quantified by an increase in plant water stress and a decrease in reservoir storage, for which the latter is mainly attributed to reforestation in the headwater catchments. While grey infrastructures like reservoir construction showed important positive impacts on some ecosystem services, such as water regulation and flood control, they also potentially induce negative impacts, such as an increase of water demand and ecological integrity. We argue that a shift is needed to green infrastructures and nature-based solutions, such as reforestation and sustainable land management, which may lead to similar benefits on ecosystem services, but without the negative impacts caused by grey infrastructures. This supports the need for integrated land-use management to sustainably protect ecosystem services, considering the expected climate change impacts on Mediterranean environments and societies.

Identifying climate change hotspots relevant for ecosystems in Romania

Studies regarding species distribution, resilience and adaptability of different ecosystems as well as the response of human society are linked with our ability to identify past and predict future changes. Climate change, together with other changes like land use, land cover and invasive alien species, are important to establish the background for further modelling approaches (e.g. species modelling, ecosystem resilience, etc.). We used high-quality and homogeneous air temperature and precipitation data sets for Romania in order to detect climate change hotspots. The changes were quantified considering 2 periods: 1961-1986 (reference) and 1987-2013 (current conditions). Bioclimatic variables were used to identify the climate change hotspots relevant for different decision makers. The identification of areas affected by significant changes may support the development of mitigation plans for enhancing the resilience and adaptive capacity of socio-economical systems to future impacts.

Why Is the Mediterranean a Climate Change Hot Spot?

AbstractHigher precipitation is expected over most of the world’s continents under climate change, except for a few specific regions where models project robust declines. Among these, the Mediterranean stands out as a result of the magnitude and significance of its winter precipitation decline. Locally, up to 40% of winter precipitation could be lost, setting strong limits on water resources that will constrain the ability of the region to develop and grow food, affecting millions of already water-stressed people and threatening the stability of this tense and complex area. To this day, however, a theory explaining the special nature of this region as a climate change hot spot is still lacking. Regional circulation changes, dominated by the development of a strong anomalous ridge, are thought to drive the winter precipitation decline, but their origins and potential contributions to regional hydroclimate change remain elusive. Here, we show how wintertime Mediterranean circulation trends can be seen as the combined response to two independent forcings: robust changes in large-scale, upper-tropospheric flow and the reduction in the regional land–sea temperature gradient that is characteristic of this region. In addition, we discuss how the circulation change can account for the magnitude and spatial structure of the drying. Our findings pave the way for better understanding and improved modeling of the future Mediterranean hydroclimate.

First indications of seasonal and spatial variations of water sources in pine trees along an elevation gradient in a Mediterranean ecosystem derived from δ18O

Water availability is the most important factor for the vitality of forest ecosystems, especially in dry environments. The Mediterranean region is one of the hotspots of future climate change; therefore, data on the water cycle are urgently needed. We measured oxygen isotope compositions in creek water, precipitation, stem water, needle water, and tree-ring cellulose over one growing season to establish the relationship between isotope compositions in different compartments along a fractionation pathway. We analyzed plant material from pine trees (Pinus nigra J.F. Arn subsp. laricio (Poiret) Maire var. Corsicana Hyl. and Pinus pinaster Aiton) at five locations along an elevation gradient from sea level to 1600 m asl. We traced back the oxygen isotope composition from source to sink in tree-ring cellulose in order to identify the water sources used by the trees, and to quantify the extent of isotope fractionation processes. Our results showed that the trees used different water sources over the course of the growing season, ranging from winter snow meltwater to summer precipitation at higher sites and deep soil water reservoirs at coastal sites. Needle water enrichment was higher at higher elevation sites than at coastal locations, highlighting the importance of site-specific climate conditions on the isotopic composition values in tree material. Water availability seems to be most restricted at the highest site, making these trees most vulnerable to climate change.

Climate change projections and extremes for Costa Rica using tailored predictors from CORDEX model output through statistical downscaling with artificial neural networks

AbstractDespite intense research on climate change (CC), regional studies for Central America, which is considered a CC hot spot, remain scarce. The information provided by general circulation models (GCMs) is too coarse to accurately reproduce local‐scale climatic features, which are needed for impact assessment. Thus, downscaling techniques are employed to address this scale mismatch. Costa Rica is the present case study, for which suitable predictors were tailored for downscaling related to regional climatic characteristics, such as the Inter‐Tropical Convergence Zone, El Niño Southern Oscillation, the Caribbean Low‐Level Jet, and the Mid‐Summer Drought. Statistical downscaling models were calibrated for precipitation, maximum and minimum temperature, using the perfect prognosis methodology by means of station data, ERA‐INTERIM reanalysis and artificial neural networks, yielding satisfactory results. As found in several studies, the temperature models replicated more accurately the statistics of the observed datasets. However, here, through the implemented approach and the tailored predictors, the precipitation models conveyed an improvement compared to standard methods. Projected daily climate was obtained employing CORDEX data under the RCP8.5 scenario for the central region of the country. Overall, the changes in climate estimated by the end of the 21st century agree with coarser‐scale projections. Finally, projected climate extremes indices were calculated and rendered further details on the intensity of future CC by the end of the century.

Identifying Local-Scale Weather Forcing Conditions Favorable to Generating Iberia’s Largest Fires

The Mediterranean region is characterized by the frequent occurrence of summer wildfires, representing an environmental and socioeconomic burden. Some Mediterranean countries (or provinces) are particularly prone to large fires, namely Portugal, Galicia (Spain), Greece, and southern France. Additionally, the Mediterranean basin corresponds to a major hotspot of climate change, and anthropogenic warming is expected to increase the total burned area due to fires in Mediterranean Europe. Here, we propose to classify summer large fires for fifty-four provinces of the Iberian Peninsula according to their local-scale weather conditions and fire danger weather conditions. A composite analysis was used to investigate the impact of local and regional climate drivers at different timescales, and to identify distinct climatologies associated with the occurrence of large fires. Cluster analysis was also used to identify a limited set of fire weather types, each characterized by a combination of meteorological conditions. For each of the provinces, two significant fire weather types were identified—one dominated by high positive temperature anomalies and negative humidity anomalies, and the other by intense zonal wind anomalies with two distinct subtypes in the Iberian Peninsula., allowing for the identification of three distinct regions.