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Beside climate‐change‐induced sea‐level rise (SLR), land subsidence can strongly amplify coastal risk in flood‐prone areas. Mapping and quantifying contemporary vertical land motion (VLM) at continental scales has long been a challenge due to the absence of gridded observational products covering these large domains. Here, we fill this gap by using the new European Ground Motion Service (EGMS) to assess the current state of coastal VLM in Europe. First, we compare the InSAR‐based EGMS Ortho (Level 3) with nearby global navigation satellite systems (GNSS) vertical velocity estimates and show that the geodetic reference frame used to calibrate EGMS strongly influences coastal vertical land velocity estimates at the millimeter per year level and this needs to be considered with caution. After adjusting the EGMS vertical velocity estimates to a more updated and accurate International Terrestrial Reference Frame (ITRF2014), we performed an assessment of VLM in European low elevation coastal flood plains (CFPs). We find that nearly half of the European CFP area is, on average, subsiding at a rate faster than 1 mm/yr. More importantly, we find that urban areas and populations located in the CFP experience a near −1 mm/yr VLM on average (excluding the uplifting Fennoscandia region). For harbors, the average VLM is even larger and increases to −1.5 mm/yr on average. This demonstrates the widespread importance of continental‐scale assessments based on InSAR and GNSS to better identify areas at higher risk from relative SLR due to coastal subsidence. Plain Language Summary: Land subsidence increases the risk of flooding in low‐lying coastal zones by amplifying relative sea‐level rise (SLR). In this study, we assess for the first time current coastal land subsidence at the scale of Europe using the new Copernicus European Ground Motion Service (EGMS) that was released in 2022. Our results suggest that nearly half of the low‐lying coastal areas in Europe are currently subsiding at a rate faster than 1 mm/yr on average. We find that coastal subsidence is higher on average in areas hosting more people, urban centers and critical infrastructure. This raises concerns that coastal subsidence, and therefore relative SLR, tends to be underestimated in Europe and presumably in many other regions around the world. Our study demonstrates that emerging continental‐scale land motion services such as EGMS are useful to better characterize the issue and anticipate coastal risks and adaptation accordingly. Key Points: Continental‐scale coastal land motion assessment in Europe is performed based on the European Ground Motion Service released in 2022European flood‐prone coastal cities subside on average at 1 mm/yr (Fennoscandia excluded)The geocentric reference frame used to calibrate continental‐scale land motion affects the results for geodetic (non‐geophysical) reasons [ABSTRACT FROM AUTHOR]

The impacts of climate change on people’s livelihoods have been widely documented.1 It is expected that climate and environmental change will hamper poverty reduction, or even exacerbate poverty in some or all of its dimensions. Changes in the biophysical environment, such as droughts, flooding, water quantity and quality, and degrading ecosystems, are expected to affect opportunities for people to generate income. These changes, combined with a deficiency in coping strategies and innovation to adapt to particular climate change threats, are in turn likely to lead to increased economic and social vulnerability of households and communities, especially amongst the poorest.

Synthesizing the extensive and ever‐growing climate change literature is becoming increasingly challenging using conventional review processes, yet is crucial to understand key trends, including knowledge and policy related gaps, managing widespread impacts, and prioritizing future efforts. Here, we employ a systematic approach to interrogate ~130,000 international peer‐reviewed climate change articles published between 1990 and 2021. We examine the time–space evolution of research topics and international collaborations, providing insights into broad scale climate change research themes, how they are developed and/or are interconnected. Our analyses indicate that significant thematic adjustments have occurred over the past three decades. Whilst all major areas of climate research have grown in output metrics, there has been a relative shift from understanding the physical science basis toward evaluating climate change impacts, adaptation, and mitigation. There has also been a significant internationalization of climate research with the ratio of international over domestic research increasing from 0.05 in 1990 to nearly 0.60 in 2021. These findings reveal a growing need for collective and coupled adaptation‐mitigation actions to address climate change. The repeatable method and overall results presented herein can help to complement existing large‐scale literature assessments, such as future IPCC reports. This article is categorized under:Climate, History, Society, Culture > Disciplinary PerspectivesIntegrated Assessment of Climate Change > Methods of Integrated Assessment of Climate Change [ABSTRACT FROM AUTHOR]

Tropical delta regions are at risk of multiple threats including relative sea level rise and human alterations, making them more and more vulnerable to extreme floods, storms, surges, salinity intrusion, and other hazards which could also increase in magnitude and frequency with a changing climate. Given the environmental vulnerability of tropical deltas, understanding the interlinkages between population dynamics and environmental change in these regions is crucial for ensuring efficient policy planning and progress toward social and ecological sustainability. Here, we provide an overview of population trends and dynamics in the Ganges-Brahmaputra, Mekong and Amazon deltas. Using multiple data sources, including census data and Demographic and Health Surveys, a discussion regarding the components of population change is undertaken in the context of environmental factors affecting the demographic landscape of the three delta regions. We find that the demographic trends in all cases are broadly reflective of national trends, although important differences exist within and across the study areas. Moreover, all three delta regions have been experiencing shifts in population structures resulting in aging populations, the latter being most rapid in the Mekong delta. The environmental impacts on the different components of population change are important, and more extensive research is required to effectively quantify the underlying relationships. The paper concludes by discussing selected policy implications in the context of sustainable development of delta regions and beyond.