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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]

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]

We produce projections of global mean sea‐level rise to 2500 for low and medium emissions scenarios (Shared Socioeconomic Pathways SSP1‐2.6 and SSP2‐4.5) relative to 2020, based on extending and combining model ensemble data from current literature. We find that emissions have a large effect on sea‐level rise on these long timescales, with [5, 95]% intervals of [0.3, 4.3]m and [1.0, 7.6]m under SSP1‐2.6 and SSP2‐4.5 respectively, and a difference in the 95% quantile of 1.6 m at 2300 and 3.3 m at 2500 for the two scenarios. The largest and most uncertain component is the Antarctic ice sheet, projected to contribute 5%–95% intervals of [−0.1, 2.3]m by 2500 under SSP1‐2.6 and [0.0, 3.8]m under SSP2‐4.5. We discuss how the simple statistical extensions used here could be replaced with more physically based methods for more robust predictions. We show that, despite their uncertainties, current multi‐centennial projections combined into multi‐study projections as presented here can be used to avoid future "lock‐ins" in terms of risk and adaptation needs to sea‐level rise. Plain Language Summary: Sea levels are predicted to rise for hundreds to thousands of years, even if emissions are reduced. Decisions about how to adapt to more frequent and severe coastal flooding need predictions showing a range of possible futures. However, few computer modeling studies of the contributing factors to sea level rise extend as far as the year 2300, and few to 2500. We present illustrative predictions of global mean sea level rise for low and medium emissions scenarios to 2500 by combining previous modeling studies and extending them where necessary. We take the widest possible range when combining studies, to show many possible futures. Predictions for global average sea level rise are 0.3–4.3 m at 2500 for the low emissions scenario, where global warming stays below around 2°C. Under medium emissions, where long‐term warming is predicted to be around 2–5°C, the predictions are around double this: from 1.0 to 7.6 m. Our aim is to outline possible long‐term futures based on physical understanding, so decision‐makers can analyze potential implications for society and avoid making decisions that are difficult to change later. We describe some potential applications of our projections, as well as key knowledge gaps and future research directions. Key Points: Projections of global mean sea‐level rise to 2500 have [5, 95]% intervals of [0.3, 4.3]m under SSP1‐2.6 and [1.0, 7.6]m under SSP2‐4.5The most uncertain sea‐level contributor continues to be the Antarctic ice sheet, with multiple studies considered to build a projectionDespite the uncertainties, our projections can be used to analyze their societal implications and recognize and potentially avoid lock‐ins [ABSTRACT FROM AUTHOR]