Earths Future最新文献

Field et al. (2018, https://doi.org/10.1029/2018ef000820) had proposed spreading hollow glass microspheres (HGMs) over Arctic sea ice to increase its albedo. Webster and Warren (2022, https://doi.org/10.1029/2022ef002815) assessed that proposal with a radiative transfer model that used (a) HGMs with optical properties published by Field et al., indicating 10% absorption by a thin layer, and (b) hypothetical non-absorbing HGMs. Strawa et al. (2025, https://doi.org/10.1029/2024ef004749) have now obtained updated optical properties indicating that HGMs are less absorptive than previously thought. However, field experiments produce less albedo-enhancement than predicted by radiative transfer models, by 0.1 or more, regardless of which value of HGM absorptance is used in the model.

Flooding has become an escalating threat over the past years, driven by climate, land use and socio-economic changes. In Europe, floods now surpass other natural disasters in severity, causing substantial economic losses, particularly in the companies (commercial and industrial sectors). While river flood impacts on agriculture and residential properties have been extensively studied, research on companies losses remain limited despite their significantly high direct damages. This study enhances fluvial flood risk assessment for company assets by integrating flood hazard scenarios with flexible state-of-the-art Bayesian Network-based flood loss model and object-specific exposure data. It estimates the expected annual damage (EAD) to company properties across Europe under a baseline and potential future scenarios shaped by climate change, exposure dynamics, and their combined effects. Additionally, the study assesses the potential of property-level precautionary measures to mitigate flood risks. Results indicate that, compared to the baseline (year—1995), the EAD values could rise more than 5-fold under RCP4.5 scenario and 7-fold under RCP8.5 scenario by the end of the century. However, a policy scenario in which all companies implement at least one precautionary measure (“measures for all”) effectively offsets these projected losses by up to 67%. This underscores the crucial role of individual actions in reducing future flood impacts.

Migrant laborers typically work long hours at physically demanding tasks without air conditioning, and they account for a considerable fraction of India's population—a share that is increasing with urban growth. However, changes in heat stress and labor capacity in major urban centers that attract rural-to-urban work migrants remain unexplored. Moreover, it remains unclear how the increased heat stress and reduced labor capacity under the warming climate will alter the most preferred workplaces for migrant laborers in India. Here, we use station-based observations, reanalysis data, and climate model projections to reconstruct trends and variability in heat stress metrics, including wet-bulb temperature for indoor exposure and wet-bulb globe temperature for outdoor exposure based on migrant data from the 2011 Census. We show that during 1980–2021, most rural-to-urban migration hotspots in north, east, and southern India witnessed a significant (p < 0.05) rise in Tw, indicating elevated indoor heat stress. Over that interval, outdoor heat stress has considerably increased and led to a ∼10% decline in labor capacity in these hotspots. A substantial rise in the indoor and outdoor heat stress exposure of migrants and a reduction in their physical labor capacity is projected with each additional degree of global warming. El Niño-Southern Oscillation variability can also significantly enhance these effects. Effective mitigation and adaptation options are needed to reduce the risks migrant workers face due to increasing indoor and outdoor heat stress in India.

Climate change manifests in the ocean as chronic stressors, including warming, acidification and deoxygenation, and as acute stressors such as marine heatwaves. While marine protected areas (MPAs) are often designed to mitigate local stressors such as fishing and mining, their design seldom considers climate change. Using the Australian marine estate as a case study, we use projections from 11 CMIP6 Earth System Models to assess the climate exposure of Australian waters, and implications for the MPA network. We find that, under scenarios that exceed 1.8°C of global surface warming this century, ocean climate is projected to surpass recent variability (1995–2014) from mid-century. This results in the disappearance of climate analogs—where future ocean conditions remain within recent variability—and of climate refugia—regions with slowest rates of environmental change, most likely to retain biodiversity—by 2040. Australian MPAs and unprotected areas exhibit similar patterns of exposure to warming, acidification, deoxygenation, and marine heatwaves, suggesting that MPA placement with respect to future climate is no better than random. Despite potential re-emergence of climate refugia after 2060 under lower-emissions scenarios, continued emissions under current Nationally Determined Contributions (SSP2–4.5) risk ecosystem collapse from chronic and acute thermal stress across protected and unprotected waters. While cutting emissions can partially cap or delay climate impacts, even under lower-emissions scenarios, effective conservation requires adaptive strategies that protect biodiversity in place and on the move.

Ports are often perceived as sources of disruption to coastal environments, contributing to sediment imbalance, shoreline erosion and ecosystem service loss. However, this framing overlooks the broader, system-scale influence that ports can exert on coastal dynamism and flood risk. In this study, we introduce the concept of the port footprint and showcase its assessment, encompassing the physical, functional and socio-economic imprint of port infrastructure on adjacent coasts. The port footprint concept integrates long-term morphodynamic modeling, flood simulation, and economic valuation to quantify both the protective and disruptive effects of ports on coastal flood and erosion risks. We illustrate this concept along a 40 km coastal stretch of the Spanish Mediterranean influenced by the Port of Valencia, evaluating how port presence interacts with sea-level rise scenarios and beach management strategies to shape future shoreline evolution, flood risk and recreational service loss. Results show that while ports may reduce beach area and affect recreational value, their flood protection benefits can outweigh these losses, particularly when combined with proactive beach management. Crucially, this work does not aim to minimize the environmental impacts of ports, but rather to demonstrate that excluding existing infrastructure from adaptation assessments risks overlooking strategic opportunities for integrated planning, especially in urbanized, infrastructure-dense coastlines.

Most of the global population lives in lowlands, where water demand is highest. Therefore, understanding the dependence of lowland regions on mountain water at a global scale is crucial as mountains provide an essential contribution to lowland water resources. Yet, interannual variability remains poorly studied in this context, although it is a key factor influencing water supply and demand. In this study, we used global simulations to contrast lowland and mountain runoff and future changes across all river basins larger than 10,000 km² globally, focusing on seasonality and interannual variability. We also examined the contribution of mountain runoff to lowland water use, its seasonality and interannual variability and its potential future changes. Our results indicate that relative interannual runoff variability is lower in mountain regions compared to lowlands in 70% of river basins. Lowland water use exhibits considerable interannual variability with greater reliance on mountain runoff during years with low lowland runoff. By the end of the century, under the SSP5-8.5 pathway, the absolute volume of lowland water abstraction reliant on mountain runoff is projected to increase in most river basins compared to the past due to socio-economic changes. Yet, its share relative to total lowland surface water abstraction is projected to decline in many basins due to increased average lowland precipitation. Possible implications of such an increased reliance on mountain runoff include heightened water conflicts, as growing dependence on upstream mountain runoff may intensify transboundary challenges.

Ocean dynamics related to large-scale circulation, such as the Gulf Stream, and smaller local ocean currents are an important driver of coastal sea-level variability along the U.S. East Coast. A relevant circulation feature in Southern New England is the Shelfbreak Jet (SBJ). The SBJ flows equatorward from the Labrador Sea toward the Gulf Stream at Cape Hatteras, following the shelf break along the Northeast U.S. Coast. The SBJ and sea level are highly correlated along the Southern New England Coast, especially at timescales of 1–15 days. Since this frequency band coincides with meteorological timescales, we explore the implications for coastal flooding. We find that SBJ transport explains, on average, about 30% of the storm surge variance along Southern New England, in a statistical sense. For a specific Nor'easter storm in March 2018, SBJ dynamics are responsible for more than 90% of the storm-surge height observed during a flood 4 days after the peak of the storm. Our results suggest local ocean dynamics are an important component of storm surges in Southern New England and can contribute, in some cases, to lingering flooding after a storm has passed. Thus, our results suggest that focusing only on large-scale circulation, such as the Gulf Stream or meridional overturning, may not be complete for understanding the dynamics essential for coastal impacts. We recommend that the role of local ocean dynamics in floods should be investigated further in other regions.

Indigenous-led Nature-based Solutions (“Indigenous-led NbS”), such as Indigenous Protected Conserved Areas and Indigenous Guardians programs, may represent a unique opportunity to advance climate and biodiversity targets grounded in Indigenous self-determination. Previous studies have comprehensively explored the scope and potential environmental outcomes of Indigenous-led NbS. Here, we build on this literature to assess how government support for Indigenous-led NbS influences climate and biodiversity outcomes. Specifically, we estimate the contribution of Indigenous-led NbS funded by the federal Government of Canada in conserving carbon stocks and biodiversity across terrestrial ecosystems. Using geospatial analysis and quasi-experimental methods, our results indicate that Indigenous-led NbS are as effective as existing Protected Areas in terms of climate change mitigation and biodiversity conservation. Moreover, our results demonstrate that government funding for Indigenous-led NbS is associated with moderate yet significant avoided land use emissions relative to Protected Areas. Based on topic-modeling applied to Indigenous-led NbS descriptions, climate and biodiversity outcomes emerge from holistic approaches to governance, intergenerational knowledge exchange, and climate-biodiversity action. Thus, government funding to Indigenous-led NbS may align biodiversity and climate outcomes with some aspects of Indigenous self-determination. The long-term alignment of these outcomes will require extended and sustained funding as well as full recognition of the rights of Indigenous Peoples.

Global warming and internal climate variability have changed winter temperature extreme regimes in North America, affecting droughts and wildfires in the western United States. However, how internal climate variability influences North American winter temperature extreme patterns remains poorly understood. Here, we demonstrate that the recent winter North American surface air temperature (SAT) exhibits an accelerated decadal alternation between Warm West-Cold East (WWCE) and Cold West-Warm East (CWWE) dipoles because their variations show shorter decadal periods during 1990–2022 than during 1950–1989 and are regulated by the Pacific Decadal Oscillation (PDO) variability. While the winter WWCE dipole mainly linked to North Pacific blocking events exhibited a smaller mean amplitude during 1990–2022 than 1950–1989 due to the weakened positive PDO phase during 1990–2022 under the positive phase of the Atlantic Multidecadal Oscillation (AMO), the winter CWWE showed a larger mean amplitude during 1990–2022 due to the stronger negative PDO phase than during 1950–1989. Our results further suggest that the recent rapid decadal shift of North American winter temperatures is primarily attributed to the PDO variability likely due to anthropogenic warming under the positive AMO.

Extreme weather events that occur concurrently are especially damaging to society, agriculture, the economy, and ecosystems. Here, we investigate the spatial distribution, trends, persistence properties, and temporal shifts of concurrent heatwaves and droughts (CHWDs) across Canada from 1979 to 2018. Our results indicate that the regions of British Columbia and the Prairies are more susceptible to a high number of CHWDs and the Arctic region is affected by less frequent but more intense CHWDs (on average 44 and 25 events respectively). The Arctic regions also have the highest increasing trend of CHWDs due to the higher trends of temperature as compared to other regions. We also explore the relationship of CHWDs with large-scale climate drivers. The North Atlantic Oscillation has the most influence on the CHWDs affecting the coastal regions and the Arctic. EP-NP and WP also show a correlation with the CHWD events occurring in central Canada. A relatively high persistence in northeast Canada, coupled with the increasing trend of the total duration of CHWDs, highlights the increasing risk of CHWDs. We note that the timing of CHWDs shifts toward early summer in parts of the Yukon and Northwest Territories and toward late summer in the Canadian Arctic Archipelago. The changes in the number of concurrent events, their total duration, and temporal shifts of occurrence should be incorporated into adaptation and mitigation policies. The rapid variability and inconsistency of CHWDs across Canada emphasize the critical need for region-specific hazard assessments that incorporate these concurrent extreme events.