Climate

31 pages, 18162 KiB

Open AccessArticle

Recovery and Reconstructions of 18th Century Precipitation Records in Italy: Problems and Analyses

by Antonio della Valle, Francesca Becherini and Dario Camuffo

Climate 2025, 13(6), 131; https://doi.org/10.3390/cli13060131 - 19 Jun 2025

Viewed by 1007

Precipitation is one of the main meteorological variables in climate research and long records provide a unique, long-term knowledge of climatic variability and extreme events. Moreover, they are a prerequisite for climate modeling and reanalyses. Like all meteorological observations, in the early period, [...] Read more.

Precipitation is one of the main meteorological variables in climate research and long records provide a unique, long-term knowledge of climatic variability and extreme events. Moreover, they are a prerequisite for climate modeling and reanalyses. Like all meteorological observations, in the early period, every observer used a personal measuring protocol. Instruments and their locations were not standardized and not always specified in the observer’s metadata. The situation began to change in 1873 with the foundation of the International Meteorological Committee, though the complete standardization of protocols, instruments, and exposure was reached in 1950 with the World Meteorological Organization. The aim of this paper is to present and discuss the methodology needed to recover and reconstruct early precipitation records and to provide high-quality dataset of precipitation usable for climate studies. The main issues that have to be addresses are described and critically analyzed based on the longest Italian precipitation series to which the methodology was successfully applied. Full article

(This article belongs to the Special Issue Climate Variability in the Mediterranean Region (Second Edition))

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17 pages, 1182 KiB

Open AccessReview

Recent Advances in Understanding the Impact of Environmental Heat Stress on Sheep Production and Reproductive Performance: A Subtropical Climate Perspective

by Jabulani Nkululeko Ngcobo, István Egerszegi and Khathutshelo Agree Nephawe

Climate 2025, 13(6), 130; https://doi.org/10.3390/cli13060130 - 18 Jun 2025

Viewed by 407

Abstract

The subtropics are affected by severe climate change, which may induce heat stress in animals. Moreover, the region is significantly seasonal; hence, mitigating climate risks and implementing climate adaptation measures are necessary. Sustainable Development Goals 1, 2, and 13 call for no poverty, [...] Read more.

The subtropics are affected by severe climate change, which may induce heat stress in animals. Moreover, the region is significantly seasonal; hence, mitigating climate risks and implementing climate adaptation measures are necessary. Sustainable Development Goals 1, 2, and 13 call for no poverty, zero hunger, and climate action. These are the most severe problems affecting food security in the modern world. Food security refers to a situation in which all people have physical, social, and economic access to sufficient, proper, and healthy food that satisfies their dietary requirements. Nevertheless, the projected increase in the human population implies a greater demand for employment opportunities; hence, developing countries are building more industrial areas. The burning of fossil fuels in various industries potentiates climate change and environmental pollution. It is predicted that the ecological temperature will increase by almost 2.3–4.8 °C by 2100 due to climate change. Agriculture and animal products remain vital in Africa as drivers of the economy and transformation for sustainable livelihood and development. Sheep production has long been used as a source of income and livelihood and provides jobs for people who live in rural areas. It is also sometimes used for ritual ceremonies and to pay penalties to local authorities. Nevertheless, sheep have been identified to be sensitive to heat stress, characterized by low reproductive performance, low microbiota quantities, and poor general health. There are different strategies for mitigating heat stress; however, many smallholder farmers have limited access to education and lack the financial support required to incorporate artificial shade and plant trees for shade to limit heat stress. In this review, we aim to understand the effects of environmental heat stress on sheep production and reproductive performance. Based on this review, it can be concluded that heat stress can threaten food security if not addressed, especially for farmers who depend on sheep rearing. As a result, future studies are recommended to understand different adaptation methods that can be used to mitigate the heat stress effect on sheep productivity, reproductivity, and general health. Full article

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20 pages, 5436 KiB

Open AccessArticle

Hydrologic and Hydraulic Modeling for Flood Risk Assessment: A Case Study of Periyar River Basin, Kerala, India

by S. Renu, Beeram Satya Narayana Reddy, Sanjana Santhosh, Sreelekshmi, V. Lekshmi, S. K. Pramada and Venkataramana Sridhar

Climate 2025, 13(6), 129; https://doi.org/10.3390/cli13060129 - 18 Jun 2025

Viewed by 601

Abstract

Floods pose a substantial threat to both life and property, with their frequency and intensity escalating due to climate change. A comprehensive hydrological and hydraulic modeling approach is essential for understanding flood dynamics and developing effective future flood risk management strategies. The accuracy [...] Read more.

Floods pose a substantial threat to both life and property, with their frequency and intensity escalating due to climate change. A comprehensive hydrological and hydraulic modeling approach is essential for understanding flood dynamics and developing effective future flood risk management strategies. The accuracy of Digital Elevation Models (DEMs) directly impacts the reliability of hydrologic simulations. This study focuses on evaluating the efficacy of two DEMs in hydrological modeling, specifically investigating their potential for daily discharge simulation in the Periyar River Basin, Kerala, India. Recognizing the limitations of the Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) with the available dataset, a novel hybrid model was developed by integrating HEC-HMS outputs with an Artificial Neural Network (ANN). While precipitation, lagged precipitation, and lagged discharge served as inputs to the ANN, the hybrid model also incorporated HEC-HMS simulations as an additional input. The results demonstrated improved performance of the hybrid model in simulating daily discharge. The Hydrologic Engineering Center’s River Analysis System (HEC-RAS) was employed to predict flood inundation areas for both historical and future scenarios in the Aluva region of the Periyar River Basin, which was severely impacted during the 2018 Kerala floods. By integrating hydrological and hydraulic modeling approaches, this study aims to enhance flood prediction accuracy and contribute to the development of effective flood mitigation strategies. Full article

(This article belongs to the Special Issue Extreme Precipitation and Responses to Climate Change)

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17 pages, 976 KiB

Open AccessArticle

Exploring Impacts of Environmentally Focused Imagery on Pro-Environment Behaviours and Climate Anxiety

by Zac Coates, Scott Brown and Michelle Kelly

Climate 2025, 13(6), 128; https://doi.org/10.3390/cli13060128 - 16 Jun 2025

Viewed by 396

Abstract

Climate change poses a significant threat to sustainability and may result in psychological distress, such as climate anxiety, which may play a critical role in influencing pro-environment behaviours. This study aimed to investigate how indirect exposure to environmentally focused imagery may impact pro-environment [...] Read more.

Climate change poses a significant threat to sustainability and may result in psychological distress, such as climate anxiety, which may play a critical role in influencing pro-environment behaviours. This study aimed to investigate how indirect exposure to environmentally focused imagery may impact pro-environment behaviours and climate anxiety. A total of 283 participants completed our task, with findings indicating that participants who viewed negative environmental imagery had a significant reduction in preference for eco-friendly transportation options compared to participants in other conditions; we saw no significant difference in preference for these participants. When examining the effects of environmental imagery on climate anxiety, we found no significant differences in the level of climate anxiety based on priming condition, indicating that climate anxiety may be more robust to situational events than associated behaviours. This study identifies the potential maladaptive effects of negative climate imagery on pro-environment behaviours and highlights the trait-like nature of climate anxiety. These findings identify the potential for disengagement with behaviour due to negative messaging and imagery associated with climate change and extreme weather events. Future research should explore the long-term stability of climate anxiety and how different forms of exposure to climate change may influence climate anxiety and pro-environment behaviours. Full article

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15 pages, 6161 KiB

Open AccessArticle

Machine Learning Indicates Stronger Future Thunderstorm Downbursts Affecting Southeast Australian Airports

by Milton Speer, Lance Leslie and Shuang Wang

Climate 2025, 13(6), 127; https://doi.org/10.3390/cli13060127 - 15 Jun 2025

Viewed by 622

Abstract

Thunderstorms downbursts can be hazardous during aircraft landing and take-off. A warming climate increases low- to mid-level troposphere water vapor, typically transported from high sea-surface temperature regions. Consequently, the future occurrence and intensity of destructive wind gusts from wet microburst thunderstorms are expected [...] Read more.

Thunderstorms downbursts can be hazardous during aircraft landing and take-off. A warming climate increases low- to mid-level troposphere water vapor, typically transported from high sea-surface temperature regions. Consequently, the future occurrence and intensity of destructive wind gusts from wet microburst thunderstorms are expected to increase. Wet microbursts are downdrafts from heavily precipitating thunderstorms and are several kilometers in diameter, often producing near-surface extreme wind gusts. Brisbane airport recorded a wet microburst wind gust of 157 km/h in November 2016. Numerous locations in eastern Australia experience warm season (October to March) wet microbursts. Here, eight machine learning techniques comprising forward and backward linear regression, radial basis forward and backward support vector regression, polynomial-based forward and backward support vector regression, and forward and backward random forest selection were employed. They identified primary attributes for increased atmospheric instability by warm moist air influx from regions of high sea-surface temperatures. The climate drivers detected here are indicative of increased future eastern Australian warm season thunderstorm downbursts, occurring as wet microbursts. They suggest a greater frequency and intensity of impacts on aircraft safety and operations affecting major east coast airports, such as Sydney and Brisbane, and smaller aircraft at inland regional airports in southeastern Australia. Full article

(This article belongs to the Special Issue Extreme Weather Detection, Attribution and Adaptation Design)

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30 pages, 14172 KiB

Open AccessArticle

Synoptic and Dynamic Analyses of an Intense Mediterranean Cyclone: A Case Study

by Ahmad E. Samman

Climate 2025, 13(6), 126; https://doi.org/10.3390/cli13060126 - 15 Jun 2025

Viewed by 492

Abstract

On 3 February 2006, a powerful Mediterranean cyclone instigated a widespread dust storm across Saudi Arabia. Meteorological observations from one station recorded strong westerly to southwesterly winds, with gusts reaching 40 m/s, accompanied by thunderstorms and dust storms. This study delves into the [...] Read more.

On 3 February 2006, a powerful Mediterranean cyclone instigated a widespread dust storm across Saudi Arabia. Meteorological observations from one station recorded strong westerly to southwesterly winds, with gusts reaching 40 m/s, accompanied by thunderstorms and dust storms. This study delves into the formation and development of this significant Mediterranean cyclone, which impacted the Mediterranean basin and the Arabian Peninsula from 26 January to 4 February 2006. Utilizing ECMWF ERA5 reanalysis data, this research analyzes the synoptic and dynamic conditions that contributed to the cyclone’s evolution and intensification. The cyclone originated over the North Atlantic as cold air from higher latitudes and was advected southward, driven by a strong upper-level trough. The initial phase of cyclogenesis was triggered by baroclinic instability, facilitated by an intense upper-level jet stream interacting with a pre-existing low-level baroclinic zone over coastal regions. Upper-level dynamics enhanced surface frontal structures, promoting the formation of the intense cyclone. As the system progressed, low-level diabatic processes became the primary drivers of its evolution, reducing the influence of upper-level baroclinic mechanisms. The weakening of the upper-level dynamics led to the gradual distortion of the low-level baroclinicity and frontal structures, transitioning the system to a more barotropic state during its mature phase. Vorticity analysis revealed that positive vorticity advection and warm air transport toward the developing cyclone played key roles in its intensification, leading to the development of strong low-level winds. Atmospheric kinetic energy analysis showed that the majority of the atmospheric kinetic energy was concentrated at 400 hPa and above, coinciding with intense jet stream activity. The generation of the atmospheric kinetic energy was primarily driven by cross-contour flow, acting as a major energy source, while atmospheric kinetic energy dissipation from grid to subgrid scales served as a major energy sink. The dissipation pattern closely mirrored the generation pattern but with the opposite sign. Additionally, the horizontal flux of the atmospheric kinetic energy was identified as a continuous energy source throughout the cyclone’s lifecycle. Full article

(This article belongs to the Section Weather, Events and Impacts)

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33 pages, 8525 KiB

Open AccessArticle

Assessment of Run-of-River and Hydropower Plants in Peru: Current and Potential Sites, Historical Variability (1981–2020), and Climate Change Projections (2035–2100)

by Leonardo Gutierrez, Adrian Huerta, Harold Llauca, Luc Bourrel and Waldo Lavado-Casimiro

Climate 2025, 13(6), 125; https://doi.org/10.3390/cli13060125 - 12 Jun 2025

Viewed by 1471

Abstract

Hydropower is the main source of renewable energy and the most feasible for implementation in remote areas without access to conventional energy grids. Therefore, knowledge of actual, potential, and future perspectives of sustainable hydropower projects is decisive for their viability. This study aims [...] Read more.

Hydropower is the main source of renewable energy and the most feasible for implementation in remote areas without access to conventional energy grids. Therefore, knowledge of actual, potential, and future perspectives of sustainable hydropower projects is decisive for their viability. This study aims to estimate the present and future potential capacity of Peru’s hydropower system and from the potential small hydroelectric plants, specifically Run-of-River class. First, we employed geospatial databases and hydroclimatological products to describe the current hydropower system and potential sites for Run-of-River projects. The findings identified 11,965 potential sites for Run-of-River plants. Second, we executed and validated a hydrological model to estimate historical daily streamflows (1981–2020) and hydropower parameters for actual and potential sites. It was determined there is an installed capacity of 5.2 GW in the current hydropower system and a total potential capacity of 29.1 GW for Run-of-River plants, mainly distributed in the northern and central Andes. Finally, we evaluated future changes driven by ten global climate models under three emission scenarios (SSP1-2.6, SSP3-7.0, and SSP5-8.5), compared with the baseline period of 1981–2010 with two future time slices. The main results about capacity indicated that operational hydroelectric plants (Run-of-River plants) are projected to decrease by 0.5 to −5.4% (−7.2 to −2.2%) during 2036–2065 and by −9.2 to 3.8% (1.8 to −11.9%) during 2071–2100. These outcomes provide relevant information to support policymakers in addressing sustainable development gaps in the coming decades and stakeholders involved in the implementation and mitigation of climate change impacts on hydropower projects in Peru. Full article

(This article belongs to the Section Climate Adaptation and Mitigation)

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14 pages, 986 KiB

Open AccessArticle

The Interplay Between Climate Change Exposure, Awareness, Coping, and Anxiety Among Individuals with and Without a Chronic Illness

by Shiri Shinan-Altman and Yaira Hamama-Raz

Climate 2025, 13(6), 124; https://doi.org/10.3390/cli13060124 - 11 Jun 2025

Viewed by 479

Abstract

Climate change poses a significant threat to mental health, including the emergence of climate change anxiety (CCA). In this study, we examined whether exposure to climate-related events was associated with higher CCA through the mediating roles of climate change awareness and ecological coping [...] Read more.

Climate change poses a significant threat to mental health, including the emergence of climate change anxiety (CCA). In this study, we examined whether exposure to climate-related events was associated with higher CCA through the mediating roles of climate change awareness and ecological coping strategies and whether these pathways differed by chronic illness status. In February 2025, 600 Israeli adults (50% female; mean age ≈ 50) completed an online self-report questionnaire assessing climate change exposure, awareness, coping, and anxiety. Data were analyzed using moderated mediation models, controlling for gender, age, and education. Greater climate change exposure was associated with an increased awareness and higher use of problem-focused coping, which, in turn, predicted elevated CCA. Meaning-focused coping was not associated with anxiety overall; however, among the participants without a chronic illness, it was linked to higher CCA. Climate change awareness alone was not associated with anxiety. A significant serial mediation was found via awareness and problem-focused coping, and a moderated mediation was found via meaning-focused coping among those without a chronic illness. Coping strategies play a key role in climate change anxiety. Although health status may influence this process, tailored interventions should prioritize coping styles in climate adaptation efforts. Full article

(This article belongs to the Special Issue Confronting the Climate Change and Health Nexus: Interactions, Impacts, and Adaptation Strategies)

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23 pages, 10389 KiB

Open AccessArticle

Spatio-Temporal Meteorological Drought Distribution in the Upper Cheliff Basin (Algeria) Using SPI and SPEI Indices

by Mohamed-Sadek Messis, Katarzyna Kubiak-Wójcicka, Azeddine Mebarki and Abdelaaziz Merabti

Climate 2025, 13(6), 123; https://doi.org/10.3390/cli13060123 - 10 Jun 2025

Viewed by 641

Abstract

This study investigates the spatio-temporal distribution of meteorological drought in the upper Cheliff basin, Algeria, downstream of the Boughzoul dam, between September 1982 and August 2021. This research use two drought indices—the Standardised Precipitation Index (SPI) and the Standardised Precipitation and Evapotranspiration Index [...] Read more.

This study investigates the spatio-temporal distribution of meteorological drought in the upper Cheliff basin, Algeria, downstream of the Boughzoul dam, between September 1982 and August 2021. This research use two drought indices—the Standardised Precipitation Index (SPI) and the Standardised Precipitation and Evapotranspiration Index (SPEI)—to evaluate drought trends, frequency, duration, severity, and number of events across various time scales (1 year, 1 month, 3 months, 6 months, 9 months, and 12 months). The results identify five major drought periods (1983/84, 1993/94, 1987/88, 1999/2000–2001/2002, and 2020/21). Both the SPI and the SPEI capture the monthly variability of drought on various time scales, with different intensities. The SPEI identifies a higher number of drought events than the SPI, particularly on shorter time scales (1 and 3 months). However, at longer timescales (6, 9, and 12 months), the number of drought events detected by both indices converges. The correlation between SPI and SPEI (R ranging from 0.73 to 0.93) across the same time scales is notably high, though the lowest correlation was found in the western part of the catchment area. This suggests that for accurate meteorological drought identification in this region, particularly in its intensively irrigated agricultural areas, SPI and SPEI should be considered. Full article

(This article belongs to the Special Issue Coping with Flooding and Drought)

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28 pages, 11908 KiB

Open AccessArticle

Variability and Trends in Spring Precipitation in the Central Sector of the Iberian Peninsula (1941–2020): The Central System and Southern Iberian System

by David Espín-Sánchez, Fernando Allende-Álvarez, Nieves López-Estébanez and Jorge Olcina-Cantos

Climate 2025, 13(6), 122; https://doi.org/10.3390/cli13060122 - 10 Jun 2025

Viewed by 707

Abstract

The reduction in and irregularity of spring precipitation in Iberian latitudes over the past few decades are well-documented. This study analyses the behaviour of the accumulated series of monthly and annual spring precipitation for a broad section of the central-eastern part of the [...] Read more.

The reduction in and irregularity of spring precipitation in Iberian latitudes over the past few decades are well-documented. This study analyses the behaviour of the accumulated series of monthly and annual spring precipitation for a broad section of the central-eastern part of the peninsula between Plasencia (Western Central System) and the south-eastern part of the Iberian System over the past 70 years. The area was chosen in accordance with the layout of the mountain systems and watersheds that cross the Iberian Peninsula from the west to east. Ten-year series and trends in the precipitation values accumulated between 1951 and 2020 provided by the AEMET were analysed together with their relationship with the pressure values for the same dates modelled by the Copernicus Climate Change Service. The totals obtained show an increasing weight regarding spring precipitation for the eastern sector (40–44%) and a gradual reduction in the west (30%). These percentages show the positive trend of the ten-year values for the easternmost sector. Spring precipitation increases are observed in the easternmost areas (7 mm/decade), while the central and western sectors generally show declining values (−35 mm/decade). The atmospheric pressure at height (Z500) and surface level (Z1000) were analysed together with their relationship with accumulated precipitation, revealing a clear trend of a dominance of high pressures in Z500. Full article

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30 pages, 18981 KiB

Open AccessArticle

Climate Evolution of Agricultural and Natural Areas of Southeastern Europe According to Pinna, Johansson and Kerner Climate Indices

by Ioannis Charalampopoulos and Fotoula Droulia

Climate 2025, 13(6), 121; https://doi.org/10.3390/cli13060121 - 9 Jun 2025

Viewed by 542

Abstract

The Southeastern European territory is under severe climatic pressure owing to accelerating dry–thermal trends. The present survey illustrates the spatial and temporal evolution of the climate regime over the natural and agricultural landcover of South-eastern Europe and individual countries (Albania, Bosnia Herzegovina, Bulgaria, [...] Read more.

The Southeastern European territory is under severe climatic pressure owing to accelerating dry–thermal trends. The present survey illustrates the spatial and temporal evolution of the climate regime over the natural and agricultural landcover of South-eastern Europe and individual countries (Albania, Bosnia Herzegovina, Bulgaria, Croatia, Greece, N. Macedonia, Montenegro, Romania, Serbia, and Slovenia). For this purpose, a high spatial resolution of the Johansson Continentality index, the Kerner Oceanity index and the Pinna Combinative index was first estimated over two climatic periods (1964–1993; 1994–2023). The Johansson index depicts increasing continentality over the southern and eastern regions, majorly by the spatiotemporal expansion of the Continental climate over the agricultural and natural areas of Bulgaria (respectively, from 49.9% to 73.7% and from 13.3% to 36.8%) followed by Serbia, Romania, and Greece. The Kerner index illustrates increasing continentality over most of the study area owing to the spatiotemporal increase in the Sub-Continental climate type over the agricultural and the natural regions of Bosnia Herzegovina (from 68.6% to 84% and from 41.4% to 63.2%), N. Macedonia, Slovenia and the natural areas of Croatia and Serbia. The extension of the Continental over the agricultural and natural areas of Romania is also shown. The Pinna index exhibits an increasing aridity trend, which is more intense in the central and eastern regions. This trend is demonstrated by the higher distribution of the Semi-Dry in the second period mostly over the agricultural and natural areas of Bulgaria (2.4% to 23.1% and 0.7% to 5.8%), and a remarkable expansion of the Moderate Wet climate over both area types of Romania (from 3.3% to 44.8% and from 5.6% to 15.2%) and Bosnia Herzegovina (from 13.7% to 33.5% and from 3.5% to 13.2%). This study’s results highlight the necessity for intensifying adaptation plans and actions aiming at the feasibility of agricultural practices and the conservation of natural areas. Full article

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19 pages, 7119 KiB

Open AccessArticle

Effects of Sea Level Rise on Hydrodynamics and Spatial Variation in Mexican Coastal Wetlands Along the Pacific Americas Flyway

by Román Alejandro Canul Turriza, Violeta Z. Fernández-Díaz, Roselia Turriza Mena, Karla Gabriela Mejía-Piña and Oscar May Tzuc

Climate 2025, 13(6), 120; https://doi.org/10.3390/cli13060120 - 6 Jun 2025

Viewed by 643

Abstract

Globally, coastal wetlands are among the most dynamic and important environments due to their wide range of environmental services, from which coastal communities benefit. Mexico has coastal wetlands that are a priority in the Pacific Flyway in America, since every year millions of [...] Read more.

Globally, coastal wetlands are among the most dynamic and important environments due to their wide range of environmental services, from which coastal communities benefit. Mexico has coastal wetlands that are a priority in the Pacific Flyway in America, since every year millions of shorebirds use these wetlands to reproduce and rest during their migration, in addition to various species that live there and are under some protection standard or in danger of extinction. In addition, these Mexican wetlands are also spaces from which important growing coastal communities benefit. However, the conservation of these coastal sites will be compromised in the coming decades by sea level rise and increasing pressure derived from coastal development, which directly impact the potential loss of space and consequently the decrease in migratory bird populations. This work identifies hydrodynamic changes and the effects of sea level rise in five coastal wetlands in Mexico and the Pacific Flyway in America, focusing on the future availability of space and the potential loss of ecosystem services under projected scenarios. The results generated give us a knowledge base to design strategies focused on the conservation and resilience of these wetlands in the face of sea level rise. Full article

(This article belongs to the Special Issue Coastal Hazards under Climate Change)

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28 pages, 6817 KiB

Open AccessReview

Resilience and Decline: The Impact of Climatic Variability on Temperate Oak Forests

by Iulian Bratu, Lucian Dinca, Cristinel Constandache and Gabriel Murariu

Climate 2025, 13(6), 119; https://doi.org/10.3390/cli13060119 - 3 Jun 2025

Cited by 1 | Viewed by 830

Abstract

Oak forests are an important part of temperate European ecosystems, where they are actively improving biodiversity, carbon storage, and ecological stability. However, current concerns such as climatic changes, and especially rising temperatures and changing precipitation patterns, are impacting their resilience. In this context, [...] Read more.

Oak forests are an important part of temperate European ecosystems, where they are actively improving biodiversity, carbon storage, and ecological stability. However, current concerns such as climatic changes, and especially rising temperatures and changing precipitation patterns, are impacting their resilience. In this context, our study intends to evaluate the impact of climatic variability on temperate oak forests, focusing on the influence of temperature and precipitation. This covers different sites that have different environmental conditions. By using both a bibliometric approach and a systematic analysis of publications that have studied the influence of climate change on oak forests, our study has identified specific species and site responses to climate stressors. Furthermore, we have also evaluated trends in drought sensitivity. All these aspects have allowed us to understand and suggest improvements for the impact of climate change on the resilience and productivity of oak ecosystems. We have analyzed a total number of 346 publications that target the impact of climate change on oak forests. The articles were published between 1976 and 2024, with the majority originating from the USA, Spain, Germany, and France. These studies were published in leading journals from Forestry, Environmental Sciences, and Plant Sciences, among which the most cited journals were Forest Ecology and Management, the Journal of Biogeography, and Global Change Biology. As for the keywords, the most frequent ones were climate change, drought, growth, forest, and oak. However, we have observed a trend towards drought sensitivity, which indicates the intensification of climate changes on oak ecosystems. Moreover, this trend was more present in central and southern regions, which further highlights the impact of regional conditions. As such, certain local factors (soil properties, microclimate) were also taken into account in our study. Our literature review focused on the following aspects: Oak species affected by climate change; Impact of drought on oak forests; Influence of climate change on mixed forests containing oaks; Effects of climate change on other components of oak ecosystems; Radial growth of oaks in response to climate change; Decline of oak forests due to climate change. Our results indicate that oak forests decline in a process caused by multiple factors, with climate change being both a stressor and a catalyst. Across the globe, increasing temperatures and declining precipitation affect these ecosystems in their growth, functions, and resistance to pathogens. This can only lead to an increased forest decline. As such, our results indicate the need to implement forest management plans that take into account local conditions, species, and climate sensitivity. This approach is crucial in improving the adaptivity of oak forests and mitigating the impact of future climate extremes. Full article

(This article belongs to the Special Issue Forest Ecosystems under Climate Change)

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35 pages, 7654 KiB

Open AccessArticle

Developing Early Warning Systems in Vanuatu: The Influence of Climate Variables on Malaria Incidence and Cattle Heat Stress

by Jade Sorenson, Emmylou Reeve, Hannah Weinberg, Andrew B. Watkins and Yuriy Kuleshov

Climate 2025, 13(6), 118; https://doi.org/10.3390/cli13060118 - 3 Jun 2025

Viewed by 533

Abstract

In the South Pacific, an increase in the frequency of climate hazards has resulted in worsened human and animal health outcomes, revealing the need for strengthened early warning to increase hazard preparedness. As Vanuatu is one of the most at-risk countries to natural [...] Read more.

In the South Pacific, an increase in the frequency of climate hazards has resulted in worsened human and animal health outcomes, revealing the need for strengthened early warning to increase hazard preparedness. As Vanuatu is one of the most at-risk countries to natural disasters, an early warning system (EWS) for climate hazards is essential to support industries and communities. Notably, climate variability has been found to exacerbate communicable disease burden and compromise livestock health and productivity; however, forecasting of such hazards and their compounding effects has not been developed in Vanuatu. Therefore, our study aims to explore EWSs that monitor and predict the impact of climate variables on malaria incidence and cattle heat stress in Vanuatu. Using monthly precipitation and temperature, a Bayesian model was developed to predict provincial malaria case burden in Vanuatu. Additionally, this study developed a weekly forecasting model to predict periods of cattle heat stress. This model used the Heat Load Index (HLI) as a proxy for heat stress to identify periods of increased heat load and antecedent conditions for cattle heat stress across the provinces. This study was successful in establishing proof-of-concept risk forecasts during selected case study periods: January 2020 and January 2016 for malaria transmission and cattle heat stress, respectively. To contribute towards a future multi-hazard EWS framework for climate hazards in Vanuatu, bulletins for predicted climate-based malaria transmission and cattle heat stress risk were developed to inform key decision makers. Intended to enhance preparedness for malaria outbreaks and cattle heat stress events, this study’s exploration of EWSs can support the resilience of Vanuatu’s public health and agricultural sectors in the face of escalating climate challenges. Full article

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20 pages, 3046 KiB

Open AccessArticle

Assessment of Maximum Snow-Water Equivalent in the Uba River Basin (Altai) Using the Temperature-Based Melt-Index Method

by Nikolay I. Bykov, Roman Yu. Birjukov, Andrey A. Bondarovich, Nurkhat K. Zhakiyev and Alexandr D. Djukarev

Climate 2025, 13(6), 117; https://doi.org/10.3390/cli13060117 - 3 Jun 2025

Viewed by 488

Abstract

The assessment of the maximum snow-water equivalent in mountains is important for understanding the mechanism of their formation, as well as for hydrological calculations. The low density of the observation network and the high complexity of ground-based snow-measuring operations have led to the [...] Read more.

The assessment of the maximum snow-water equivalent in mountains is important for understanding the mechanism of their formation, as well as for hydrological calculations. The low density of the observation network and the high complexity of ground-based snow-measuring operations have led to the widespread use of remote methods to obtain such data. In this study, the maximum water reserve of the Uba River basin was calculated for the period of 2020–2023, based on data from the Sentinel-2 satellite regarding the position of the seasonal snow line, obtained using the temperature-based melt-index method. This study determined the snowmelt coefficients for the meteorological stations at Zmeinogorsk, Shemonaikha, and Ridder. Maps were constructed to show the distribution of the maximum snow-water equivalent in the Uba River basin. The spatial differentiation features of the snow cover were revealed, depending on the elevation, slope exposure, and distance from the watersheds. It was established that the altitudinal distribution of snow cover on the northern and southern macro-slopes of the ridges is asymmetric: in the western part of the basin, within the elevation range of 500–1200 m, the maximum water reserves of snow cover are greater on the southern slopes, but they become higher on the northern slopes above 1200 m. In the eastern part of the basin, they are always larger on the northern slopes. The greatest differences in the distribution of snow cover between the slopes occur near the watersheds. Full article

(This article belongs to the Section Climate and Environment)

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18 pages, 15631 KiB

Open AccessArticle

Resolving the Faint Young Sun Paradox and Climate Extremes: A Unified Thermodynamic Closure Theory

by Hsien-Wang Ou

Climate 2025, 13(6), 116; https://doi.org/10.3390/cli13060116 - 2 Jun 2025

Viewed by 492

Abstract

Clouds play a central role in regulating incoming solar radiation and outgoing terrestrial emission; hence, they must be internally constrained to prognose Earth’s temperature. At the same time, planetary fluids are inherently turbulent, so the climate state would tend toward maximum entropy production—a [...] Read more.

Clouds play a central role in regulating incoming solar radiation and outgoing terrestrial emission; hence, they must be internally constrained to prognose Earth’s temperature. At the same time, planetary fluids are inherently turbulent, so the climate state would tend toward maximum entropy production—a generalized second law of thermodynamics. Incorporating these requirements, I have previously formulated an aquaplanet model to demonstrate that intrinsic water properties may strongly lower the climate sensitivity to solar irradiance, thereby resolving the faint young Sun paradox (FYSP). In this paper, I extend the model to include other external forcings and show that sensitivity to the reduced outgoing longwave radiation by the elevated pCO₂ can be several times greater, but the global temperature remains capped at ~40 °C by the exponential increase in saturated vapor pressure. I further show that planetary albedo augmented by a tropical supercontinent may cool the climate sufficiently to cause tropical glaciation. And since the glacial edge is marked by above-freezing temperature, it abuts an open, co-zonal ocean, thereby obviating the “Snowball Earth” hypothesis. Our theory thus provides a unified framework for interpreting Earth’s diverse climates, including the FYSP, the warm extremes of the Cambrian and Cretaceous, and the tropical glaciations of the Precambrian. Full article

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29 pages, 1076 KiB

Open AccessArticle

Uncertain Box–Cox Regression for Modeling the Spatial Coupling of Extreme Weather Events and Economic Impacts in the Chengdu-Chongqing Region

by Kun Bai, Jun He, Xiaoqing Fan and Liang Fang

Climate 2025, 13(6), 115; https://doi.org/10.3390/cli13060115 - 1 Jun 2025

Viewed by 636

Abstract

In the context of ongoing climate change, extreme weather events are becoming increasingly frequent and unpredictable, posing significant challenges for traditional probability-based methods. This study presents an innovative uncertainty-based Box–Cox regression framework to assess the impacts of climate change factors, specifically temperature and [...] Read more.

In the context of ongoing climate change, extreme weather events are becoming increasingly frequent and unpredictable, posing significant challenges for traditional probability-based methods. This study presents an innovative uncertainty-based Box–Cox regression framework to assess the impacts of climate change factors, specifically temperature and precipitation, on the volatility of extreme weather events in the Chengdu-Chongqing region. To address data imprecision, we establish a new estimation theorem for the Extended Least Squares Estimator (ELSE), proving its existence, uniqueness, unbiasedness, and variance consistency under uncertainty theory. The Mann–Kendall trend test is applied to detect event frequency trends, and a coupling coordination degree model is employed to evaluate the dynamic relationship between climate resources and economic development. The results show that (1) temperature has a more significant impact on the volatility of extreme weather events than precipitation; (2) the thermal resource–economy coupling degree has remained above 0.45 since 2015, indicating a strengthening relationship but suboptimal coordination; and (3) since 2014, the water resource–economy coupling degree has consistently exceeded 0.5, reaching optimal levels and highlighting the growing importance of water resources in regional development. Based on these findings, we recommend enhancing extreme weather monitoring systems, improving infrastructure resilience, optimizing climate-related resource management, and fostering regional cooperation. This study provides a rigorous theoretical and empirical basis for integrating uncertainty modeling into climate–economy analysis. Future work should further explore alternative modeling strategies and validate conclusions using extended datasets. Full article

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14 pages, 813 KiB

Open AccessArticle

Towards the Conceptual Framing of Inclusive Urban Flood Resilience

by Dwayne Shorlon Renville, Netra Chhetri, Chingwen Cheng, Linda Francois and Ruijie Zeng

Climate 2025, 13(6), 114; https://doi.org/10.3390/cli13060114 - 1 Jun 2025

Viewed by 1446

Abstract

The governance of cities in low-elevation zones faces many challenges. Notable among these are losses associated with regular pluvial floods and, more so, the threat of impending extreme floods due to climate change and their impacts on residents, especially amongst socially vulnerable groups. [...] Read more.

The governance of cities in low-elevation zones faces many challenges. Notable among these are losses associated with regular pluvial floods and, more so, the threat of impending extreme floods due to climate change and their impacts on residents, especially amongst socially vulnerable groups. This is exacerbated by the reliance on traditionally exclusive approaches to governance. This paper discusses the flood resilience aspect of urban planning by examining the extent of emphasis on inclusiveness in urban flood resilience literature. We relied on the synthesis of inclusive development and flood resilience literature. The findings suggest that, while inclusive development is a burgeoning aspect of development research, and studies on evaluating urban flood resilience are commonplace, the concept of inclusive urban flood resilience is still in its infancy. Furthermore, we found that while inclusive development is neither static nor finite to allow for measuring it in absolute terms, it can be applied or assessed through any or all of its guiding principles. Consequently, together with the well-established methods of implementing and assessing urban flood resilience, we present a preliminary framework for inclusive urban flood resilience as a guide for future scholarly contributions to this composite field. Scholars and practitioners of urban planning in low-elevation zones are encouraged to move away from top–down siloed approaches that result in exclusions and rely more on integrated, inclusive, and socio-ecological pathways to preserve the integrity of cities. Full article

(This article belongs to the Special Issue Coping with Flooding and Drought)

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17 pages, 1808 KiB

Open AccessArticle

Locating Urban Area Heat Waves by Combining Thermal Comfort Index and Computational Fluid Dynamics Simulations: The Optimal Placement of Climate Change Infrastructure in a Korean City

by Sinhyung Cho, Sinwon Cho, Seungkwon Jung and Jaekyoung Kim

Climate 2025, 13(6), 113; https://doi.org/10.3390/cli13060113 - 29 May 2025

Viewed by 567

Abstract

The intensification of extreme temperature events driven by climate change has heightened the vulnerability of urban areas to heatwaves, making it a critical environmental challenge. In this study, we investigate the spatial characteristics of urban heatwave vulnerability in Jungang-dong, Gangneung—a representative mid-sized coastal [...] Read more.

The intensification of extreme temperature events driven by climate change has heightened the vulnerability of urban areas to heatwaves, making it a critical environmental challenge. In this study, we investigate the spatial characteristics of urban heatwave vulnerability in Jungang-dong, Gangneung—a representative mid-sized coastal city in South Korea that experiences a strong urban heat island (UHI) effect due to the prevalent land–sea breeze dynamics, high building density, and low green-space ratio. A representative heatwave day (22 August 2024) was selected using AWS data from the Korea Meteorological Administration (KMA), and hourly meteorological conditions were applied to Computational Fluid Dynamics (CFD) simulations to model the urban microclimates. The thermal stress levels were quantitatively assessed using the Universal Thermal Climate Index (UTCI). The results indicated that, at 13:00, the surface temperatures reached 40 °C and the UTCI values peaked at 43 °C, corresponding to a “Very Strong Heat Stress” level. Approximately 17.4% of the study area was identified as being under extreme thermal stress, particularly in densely built-up zones, roadside corridors with high traffic, and pedestrian commercial areas. Based on these findings, we present spatial analysis results that reflect urban morphological characteristics to guide the optimal allocation of urban cooling strategies, including green (e.g., street trees, urban parks, and vegetated roofs), smart, and engineered infrastructure. These insights are expected to provide a practical foundation for climate adaptation planning and thermal environment improvement in mid-sized urban contexts. Full article

(This article belongs to the Special Issue Climate Adaptation and Mitigation in the Urban Environment)

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19 pages, 5289 KiB

Open AccessArticle

Citizens and Scientific Perceptions of Ecosystem Services—Assessing Local Controversies over Climate Mitigation Efforts in Drained Wetlands

by Thomas Skou Grindsted, Pernille Almlund, Jesper Holm, Gry Lyngsie, Gary Banta, Kristian Syberg, Henrik Hauggaard-Nielsen, Søren Lund and Simon David Herzog

Climate 2025, 13(6), 112; https://doi.org/10.3390/cli13060112 - 29 May 2025

Viewed by 846

Abstract

Draining wetland landscapes accelerates climate change, and multilateral support is therefore needed to speed up the transition to new land uses. This paper examines perceptions of ecosystem services (ES) in wetland areas in scientific and civic assessments. The case study area is Denmark’s [...] Read more.

Draining wetland landscapes accelerates climate change, and multilateral support is therefore needed to speed up the transition to new land uses. This paper examines perceptions of ecosystem services (ES) in wetland areas in scientific and civic assessments. The case study area is Denmark’s largest drained wetland system, which is notable for its carbon sequestration potential. The area’s transformation efforts involving public participation offer a unique chance to examine differences between scientific and civic perceptions of ES. This exceptional case is ideal for revealing contextual differences, trade-offs, and controversies between scientific and civic perceptions of ES. Millennium ES Assessment and CICES are used as a conceptual framework for understanding and mapping human–nature interactions in a nature park. However, these systems are, in practice, not sufficiently developed to identify how citizens understand and value ES in real life. Therefore, we analyse perceptions using interviews, collaborative mapping, and media analysis. We compare these to scientific ES mappings based on local data, literature reviews, and fieldwork. The paper concludes that (1) scientific ES asymmetries are important; (2) environmental blind spots in scientific ES are due to its approach to knowledge collection; (3) citizens’ blind spots are due to their everyday life focus and tabooing the issue of local climate mitigation; and (4) science-based ES assessments and accounts are disconnected from local ES controversies. We argue that identifying ES controversies through various scientific methods may improve climate mitigation and restoration efforts if community planning becomes involved. Full article

(This article belongs to the Section Climate and Environment)

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12 pages, 3793 KiB

Open AccessArticle

Semi-Annual Climate Modes in the Western Hemisphere

by Mark R. Jury

Climate 2025, 13(6), 111; https://doi.org/10.3390/cli13060111 - 27 May 2025

Viewed by 394

Abstract

Semi-annual climate oscillations in the Western Hemisphere (20 S–35 N, 150 W–20 E) were studied via empirical orthogonal function (EOF) eigenvector loading patterns and principal component time scores from 1980 to 2023. The spatial loading maximum for 850 hPa zonal wind extended from [...] Read more.

Semi-annual climate oscillations in the Western Hemisphere (20 S–35 N, 150 W–20 E) were studied via empirical orthogonal function (EOF) eigenvector loading patterns and principal component time scores from 1980 to 2023. The spatial loading maximum for 850 hPa zonal wind extended from the north Atlantic to the east Pacific; channeling was evident over the southwestern Caribbean. The eigenvector loading maximum for precipitation reflected an equatorial trough, while the semi-annual SST formed a dipole with loading maxima in upwelling zones off Angola (10 E) and Peru (80 W). Weakened Caribbean trade winds and strengthened tropical convection correlated with a warm Atlantic/cool Pacific pattern (R = 0.46). Wavelet spectral analysis of principal component time scores found a persistent 6-month rhythm disrupted only by major El Nino Southern Oscillation events and anomalous mid-latitude conditions associated with negative-phase Arctic Oscillation. Historical climatologies revealed that 6-month cycles of wind, precipitation, and sea temperature were tightly coupled in the Western Hemisphere by heat surplus in the equatorial ocean diffused by meridional overturning Hadley cells. External forcing emerged in early 2010 when warm anomalies over Canada diverted the subtropical jet, suppressing subtropical trade winds and evaporative cooling and intensifying the equatorial trough across the Western Hemisphere. Climatic trends of increased jet-stream instability suggest that the semi-annual amplitude may grow over time. Full article

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15 pages, 1236 KiB

Open AccessReview

From Climate to Cloud: Advancing Fog Detection Through Satellite Imagery

by Andrés Gabriel Arguedas Chaverri, Rogério Hartung Toppa and Kelly Cristina Tonello

Climate 2025, 13(6), 110; https://doi.org/10.3390/cli13060110 - 27 May 2025

Viewed by 569

Abstract

The broad spatiotemporal coverage provided by satellite remote sensing is fundamental for monitoring fog events, a phenomenon that impacts transportation, agriculture, and ecosystem functioning. Despite advances in remote sensing technology, significant knowledge gaps remain regarding the application of these techniques to fog detection, [...] Read more.

The broad spatiotemporal coverage provided by satellite remote sensing is fundamental for monitoring fog events, a phenomenon that impacts transportation, agriculture, and ecosystem functioning. Despite advances in remote sensing technology, significant knowledge gaps remain regarding the application of these techniques to fog detection, especially over terrestrial ecosystems. This scoping review synthesizes the trends in methods used for fog detection by analyzing 38 papers retrieved from Scopus and Web of Science. Only studies that utilized satellite imagery to analyze the spatiotemporal dynamics of fog were included. Articles that employed non-satellite methodologies or focused on processes other than the detection, formation, or identification of fog events were excluded. In addition to a term co-occurrence analysis of abstracts using VOSviewer, this study examines key parameters of the detection methods—including sensor type, spectral bands, temporal resolution, and algorithmic approaches (e.g., threshold methods and deep learning techniques)—to evaluate their evolution and current limitations. Our results reveal that while approximately 53% of studies rely on geostationary satellite data (95% CI: 36.7–68.5%), favored for their high temporal resolution, the remaining 47% employ polar-orbiting sensors (95% CI: 31.5–63.2%) that offer superior spatial resolution. Notably, most research has concentrated on maritime fog detection, with few studies extending these techniques to complex terrestrial environments. The review highlights critical gaps in current approaches and proposes an integrated framework that combines traditional brightness temperature difference methods with emerging machine learning techniques, which could advance fog detection in diverse settings. Full article

(This article belongs to the Topic Advances in Hydrological Remote Sensing)

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16 pages, 5597 KiB

Open AccessArticle

Wildfire Risk Assessment Using the Fire Weather Index (FWI) in Greece

by Effie Kostopoulou and George Stavridis

Climate 2025, 13(6), 109; https://doi.org/10.3390/cli13060109 - 26 May 2025

Viewed by 1766

Abstract

This study assesses future wildfire risk in Greece using the Fire Weather Index (FWI), based on data from the Copernicus Climate Change Service. Historical conditions (1971–2000) and future projections (2069–2098) under RCP4.5 and RCP8.5 scenarios were analyzed, with a primary focus on the [...] Read more.

This study assesses future wildfire risk in Greece using the Fire Weather Index (FWI), based on data from the Copernicus Climate Change Service. Historical conditions (1971–2000) and future projections (2069–2098) under RCP4.5 and RCP8.5 scenarios were analyzed, with a primary focus on the core fire season (May–October) and consideration of April and November to evaluate potential seasonal extension. The results show a significant shift toward higher fire risk classes, with the “very high” category increasing from 24% historically to 31% under RCP4.5 and 37% under RCP8.5, and the “extreme” class rising from 4% to 11% and 16%, respectively. Southern Greece, especially Crete, and the Dodecanese, is projected to experience the most severe increases. These changes, driven by rising temperatures and intensified drought conditions, indicate an increased likelihood of extreme fire events, posing increased risks to ecosystems, infrastructure, and regional economies. The findings highlight the need for targeted adaptation and fire management strategies. Full article

(This article belongs to the Special Issue Climate Change Impacts at Various Geographical Scales (2nd Edition))

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23 pages, 2334 KiB

Open AccessArticle

Heat Waves in Portugal During the 2001–2024 Period: An Overview

by A. Virgílio M. Oliveira, António M. Raimundo, Adélio R. Gaspar and Divo A. Quintela

Climate 2025, 13(6), 108; https://doi.org/10.3390/cli13060108 - 26 May 2025

Viewed by 1241

Abstract

The present contribution addresses the Heat Waves (HWs) which occurred in Portugal’s mainland during the first 24 years of the XXI century: the number of HWs, their frequency, duration and geographic localization, among other impacts, are described. In a complementary perspective, due to [...] Read more.

The present contribution addresses the Heat Waves (HWs) which occurred in Portugal’s mainland during the first 24 years of the XXI century: the number of HWs, their frequency, duration and geographic localization, among other impacts, are described. In a complementary perspective, due to the significant impacts of the 2003 HW, specifically in terms of mortality, a more detailed analysis of this event is performed. For the present analysis, HWs were identified using a modified version of the Heat Wave Duration Index (HWDI) proposed by the World Meteorological Organization (WMO). During the XXI century, between 2001 and 2024, 95 HWs occurred in the Portuguese mainland. In 2024, eight HWs occurred, followed by 2009, 2015 and 2017, with seven HWs each; in terms of monthly distribution, August (17) and May (16) displayed the highest values. HWs are now included in the World Health Organization agenda of natural hazards, enhancing the importance of these events. It is time to start considering HWs and their significant impacts as an important issue, especially in countries with older populations, like Portugal. Full article

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40 pages, 2557 KiB

Open AccessArticle

Regime Change in Top of the Atmosphere Radiation Fluxes: Implications for Understanding Earth’s Energy Imbalance

by Roger N. Jones and James H. Ricketts

Climate 2025, 13(6), 107; https://doi.org/10.3390/cli13060107 - 24 May 2025

Viewed by 1726

Abstract

Earth’s energy imbalance (EEI) is a major indicator of climate change. Its metrics are top of the atmosphere radiation imbalance (EEI TOA) and net internal heat uptake. Both EEI and temperature are expected to respond gradually to forcing on annual timescales. This expectation [...] Read more.

Earth’s energy imbalance (EEI) is a major indicator of climate change. Its metrics are top of the atmosphere radiation imbalance (EEI TOA) and net internal heat uptake. Both EEI and temperature are expected to respond gradually to forcing on annual timescales. This expectation was tested by analyzing regime changes in the inputs to EEI TOA along with increasing ocean heat content (OHC). Outward longwave radiation (OLR) displayed rapid shifts in three observational and two reanalysis records. The reanalysis records also contained shifts in surface fluxes and temperature. OLR, outward shortwave radiation (OSR) and TOA net radiation (Net) from the CERES Energy Balanced and Filled Ed-4.2.1 (2001–2023) record and from 27 CMIP5 historical and RCP4.5 forced simulations 1861–2100, were also analyzed. All variables from CERES contained shifts but the record was too short to confirm regime changes. Contributions of OLR and OSR to net showed high complementarity over space and time. EEI TOA was −0.47 ± 0.11 W m⁻² in 2001–2011 and −1.09 ± 0.11 W m⁻² in 2012–2023. Reduced OSR due to cloud feedback was a major contributor, coinciding with rapid increases in sea surface temperatures in 2014. Despite widely varying OLR and OSR, 26/27 climate models produced stable regimes for net radiation. EEI TOA was neutral from 1861, shifting downward in the 26 reliable records between 1963 and 1995, with 25 records showing it stabilizing by 2039. To investigate heat uptake, temperature and OHC 1955/57–2023 was analyzed for regime change in the 100 m, 700 m and 2000 m layers. The 100 m layer, about one third of total heat content, was dominated by regimes. Increases became more gradual with depth. Annual changes between the 700 m layer and 1300 m beneath were negatively correlated (−0.67), with delayed oscillations during lag years 2–9. Heat uptake at depth is dynamic. These changes reveal a complex thermodynamic response to gradual forcing. We outline a complex arrangement of naturally evolved heat engines, dominated by a dissipative heat engine nested within a radiative engine. EEI is a property of the dissipative heat engine. This far-from-equilibrium natural engine has evolved to take the path of least resistance while being constrained by its maximum power limit (~2 W m⁻²). It is open to the radiative engine, receiving solar radiation and emitting scattered shortwave and longwave radiation. Steady states maximize entropy within the dissipative engine by regulating spatial patterns in surface variables that influence outgoing OLR and OSR. Regime shifts to warmer climates balance the cost of greater irreversibility with increased energy rate density. The result is the regulation of EEI TOA through a form of thermodynamic metabolism. Full article

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17 pages, 4204 KiB

Open AccessArticle

Decadal Modulation of Summertime Northwestern Pacific Subtropical High Linked to Indian Ocean Basin Warming

by Takashi Mochizuki and Yuta Ando

Climate 2025, 13(6), 106; https://doi.org/10.3390/cli13060106 - 24 May 2025

Viewed by 603

Abstract

The Northwestern Pacific Subtropical High (NPSH), usually enhanced by the basin-scale warming of the Indian Ocean (IOBW), plays a major role in controlling the summertime East Asian climate. To assess factors contributing to the decadal modulation of the NPSH and IOBW relationship in [...] Read more.

The Northwestern Pacific Subtropical High (NPSH), usually enhanced by the basin-scale warming of the Indian Ocean (IOBW), plays a major role in controlling the summertime East Asian climate. To assess factors contributing to the decadal modulation of the NPSH and IOBW relationship in recent years, we conducted sensitivity experiments using an atmospheric general circulation model. We particularly focused on decadal-scale differences between the periods of 1982–2001 and 2002–2021, with the contribution of the climatological sea surface temperature (SST) as the background, in combination with the tropical Pacific SST anomaly in relation to the rapid or slow decay of the El Niño Southern Oscillation (ENSO). The results indicate that the IOBW-related SST anomalies in the Indian and tropical Pacific Oceans—which, overall, represent the well-known characteristics of the so-called Indo-western Pacific Ocean Capacitor effects—cooperatively enhanced the NPSH in the earlier period (1982–2001). On the other hand, the suppressed and westward-shifted SST anomalies in the tropical Pacific Ocean and the resultant changes in the diabatic heating of cumulus convection suppressed the NPSH enhancement in recent years (2002–2021). These results indicate that the modulation in the NPSH responses linked to the IOBW is primarily due to the so-called ENSO diversity rather than climatology. Full article

(This article belongs to the Section Climate Dynamics and Modelling)

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