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Bridging Knowledge Cultures: Rebalancing Power in the Co-Construction of Knowledge
(Brill, 2024) Lepore, Walter; Hall, Budd L.; Tandon, Rajesh
Establishing truly respectful, mutually beneficial, and equitable knowledge creation partnerships with diverse communities poses significant challenges for academia. Bridging Knowledge Cultures provides valuable insights into the dynamics involved and the obstacles encountered when attempting to establish meaningful research partnerships between different knowledge domains. This book goes beyond exploration by offering practical recommendations to overcome these challenges and forge effective collaboration between mainstream research institutions and community groups and organizations. This book includes ten compelling case studies conducted by research and training hubs established through the global Knowledge for Change Consortium. These case studies encompass community-university research partnerships across various geographical locations, tackling a wide range of societal issues and acknowledging the wealth of knowledge created by local communities. The overarching goal of this book is to inspire the next generation of researchers and professionals to embrace the richness of diverse perspectives and knowledge cultures. By advocating for the construction of "bridges" through practical approaches, the book encourages a shift from competition to collaboration in research. Ultimately, it aims to foster an environment where different forms of knowledge can intersect and thrive, leading to a more inclusive and comprehensive understanding of the world around us.
Should we think of observationally constrained multidecade climate projections as predictions?
(Science Advances, 2025) Li, Tong; Zwiers, Francis W.; Zhang, Xuebin
Empirical evidence indicates that the range of model-projected future warming can be successfully narrowed by conditioning the projected warming on past observed warming. We demonstrate that warming projections conditioned on the entire instrumental annual surface temperature record are of sufficiently high quality and should be considered as long-term predictions rather than merely as projections. We support this view by considering the skill of predicted 20- and 50-year lead temperature changes under the Shared Economic Pathway (SSP)1-2.6 and SSP5-8.5 emission scenarios in climates of different sensitivities. Using climate model simulations, we show that adjusting raw multimodel projections of future warming with the Kriging for Climate Change (KCC) method eliminates most biases and reduces the uncertainty of warming projections irrespective of the sensitivity of the climate being considered. Simpler methods, or using only the more recent part of the temperature record, provide less effective constraints. The high-skill future warming predictions obtained via KCC have a serious place in informing global climate policies.
Land temperature and hydrological conditions over B.C. in 2024
(Department of Fisheries and Oceans, 2025) Curry, Charles L.; Lang, Kristyn; Dah, Abigail
2024 was the second warmest year since 1940 in B.C., exceeded only by record warm temperatures in 2023. Snowpack increased from well below-normal to below-normal through the early winter, decreasing again to well below-normal by late spring. Compared to 2023 drought conditions were less severe overall; however, basins in the Northeast continued to experience extreme drought. The annual mean temperature in B.C. is increasing and can be distinguished from natural variability over the analyzed period of 1940-2024. Annual precipitation, however, exhibits no significant province-wide trend over that period.
Land temperature and hydrological conditions over B.C. in 2023
(Department of Fisheries and Oceans, 2024) Curry, Charles L.; Lang, Kristyn
In 2023, B.C. experienced record warm annual, summer and fall temperatures and well below-normal annual precipitation. Snowpack was generally below-normal through the winter, rapidly decreasing to well below-normal by June 1st due to early snowmelt across the province. In late summer and fall, severe drought conditions were experienced nearly everywhere in B.C., coinciding with record warm temperatures and below-normal precipitation. The trend in annual mean temperature in B.C. is positive and can be distinguished from natural variability over the analyzed period, 1950-2023. Annual precipitation, however, exhibits no significant trend over that period.
Constraining the entire Earth system projections for more reliable climate change adaptation planning
(Science Advances, 2025) Li, Chao; Zwiers, Francis W.; Zhang, Xuebin; Fischer, Erich M.; Du, Fujun; Liu, Jieyu; Wang, Jianyu; Liang, Yongxiao; Li, Tong; Yuan, Lina
The warming climate is creating increased levels of climate risk because of changes to the hazards to which human and natural systems are exposed. Projections of how those hazards will change are affected by uncertainties in the climate sensitivity of climate models, among other factors. While the level-of-global-warming approach can circumvent model climate sensitivity uncertainties in some applications, practitioners faced with specific adaptation responsibilities often find such projections difficult to use because they generally require time-oriented information. Earth system projections following specified emissions scenarios can, however, be constrained by applying the level-of-global-warming approach to observationally constrained warming projections to yield more reliable time-oriented projections for adaption planning and implementation. This approach also allows individual groups to produce consistent and comparable assessments of multifaceted climate impacts and causal mechanisms, thereby benefiting climate assessments at national and international levels that provide the science basis for adaptation action.
Current trends and biases in groundwater modelling using the community-driven groundwater model portal (GroMoPo)
(Hydrogeology Journal, 2025) Zamrsky, Daniel; Ruzzante, Sacha; Compare, Kyle; Kretschmer, Daniel; Zipper, Sam; Befus, Kevin M.; Reinecke, Robert; Pasner, Yara; Gleeson, Tom; Jordan, Kristen; Cuthbert, Mark; Castronova, Anthony M.; Wagener, Thorsten; Bierkens, Marc F. P.
Groundwater, Earth’s largest nonfrozen freshwater reservoir, is vital for water supply security. Groundwater models help to manage complex domestic, agricultural, and industrial water demands while preserving ecosystem health under climate change. The community-driven groundwater model portal (GroMoPo) hosts groundwater model metadata to analyse biases and distribution of groundwater models. Over 450 models are currently featured on GroMoPo, with most models from high-GDP countries at local-to-regional scales. The GroMoPo initiative addresses current knowledge gaps and facilitates future collaboration and data sharing.
Comparing global violations of environmentally critical groundwater discharge thresholds
(Water Resources Research, 2024) Marinelli, B. P. P.; Mohan, C.; Gleeson, Tom; Ludwig, F.; de Graaf, I. E. M.
Groundwater is a crucial resource to support surface water bodies via groundwater discharge. In this study, we applied two methods of estimating global environmentally critical groundwater discharge, defined as the flux of groundwater to streamflow necessary to maintain a healthy environment, from 1960 to 2010: the Presumptive Standard stipulates that a standard proportion of groundwater discharge should be maintained at all timesteps, while the Q* is a low-flow index that focuses on critical periods. We calculated these critical flow thresholds using simulated natural groundwater discharge, and estimated violations of the thresholds when human-impacted groundwater discharge dropped too low. Our global assessment of the frequency and severity of violations over all timesteps in our study period showed that the Presumptive Standard estimated more frequent and severe violations than the Q*, but that the spatial patterns were similar for both methods. During low-flow periods, when the relative importance of groundwater to support streamflow is greatest, both methods estimated similar magnitudes of violation frequency and severity. We further compared our results to a method of estimating environmentally critical streamflow, Variable Monthly Flow, which does not explicitly consider groundwater. From the differences in violation frequency between these groundwater-centric and surface water-centric methods, we evaluated the influence of including groundwater contributions to streamflow in environmental flow assessments. Our results show that including groundwater in such assessments is particularly important for regions with high groundwater demands in the drier climates of the world, while it is less important for regions with low groundwater demands and more humid climates.
Concerns regarding proposed groundwater Earth system boundary
(Nature, 2024) Cuthbert, M. O.; Gleeson, Tom; Bierkens, M. F. P.; Ferguson, G.; Taylor, R. G.
Groundwater, the largest store of accessible freshwater on Earth, is under increasing pressure as a resource1 and its over-exploitation can harm dependent ecosystems, increase the severity of hydrological drought, and cause land subsidence and salinization2. It is, therefore, a welcome development that groundwater has been explicitly incorporated in the endeavour to quantify safe and just Earth system boundaries (ESBs) in a recent article by Rockström et al.3. However, here we raise concerns about the proposed groundwater ESB, by showing how it is based on an incorrect conceptual understanding of groundwater system dynamics and nomenclature. The proposed boundary is thus potentially misleading, with important implications for assessing the global status of groundwater resources with regards to safe and just water management.
Bright but flickering lights of sustainable, community-based groundwater supply and management: ASADAS in Costa Rica
(Environmental Research Letters, 2025) Madrigal-Ballestero, Róger; Gleeson, Tom; López-Ruiz, Mariaclara; Castillo-Cruz, Aaron Benhur
Groundwater, a quintessential invisible natural resource, is often misunderstood and mismanaged due to scale and management approaches as well as geographic and disciplinary biases (Giordano 2009, Gleeson et al 2020, Lall et al 2020). While groundwater management and sustainability discussions typically focus on large scales, such as regional aquifers and global analyses (Scanlon et al 2023), it is crucial to recognize that groundwater systems and sustainability occur across multiple scales (Foster et al 2013), from individual wells to large aquifers and even global virtual groundwater trade (Dalin et al 2017).
Groundwaterscapes: A global classification and mapping of groundwater's large-scale socioeconomic, ecological, and Earth system functions
(Water Resources Research, 2024) Huggins, Xander; Gleeson, Tom; Villholth, Karen G.; Rocha, Juan C.; Famiglietti, James S.
Groundwater is a dynamic component of the global water cycle with important social, economic, ecological, and Earth system functions. We present a new global classification and mapping of groundwater systems, which we call groundwaterscapes, that represent predominant configurations of large-scale groundwater system functions. We identify and map 15 groundwaterscapes which offer a new lens to conceptualize, study, model, and manage groundwater. Groundwaterscapes are derived using a novel application of sequenced self-organizing maps that capture patterns in groundwater system functions at the grid cell level (∼10 km), including groundwater-dependent ecosystem type and density, storage capacity, irrigation, safe drinking water access, and national governance. All large aquifer systems of the world are characterized by multiple groundwaterscapes, highlighting the pitfalls of treating these groundwater bodies as lumped systems in global assessments. We evaluate the distribution of Global Groundwater Monitoring Network wells across groundwaterscapes and find that industrial agricultural regions are disproportionately monitored, while several groundwaterscapes have next to no monitoring wells. This disparity undermines the ability to understand system dynamics across the full range of settings that characterize groundwater systems globally. We argue that groundwaterscapes offer a conceptual and spatial tool to guide model development, hypothesis testing, and future data collection initiatives to better understand groundwater's embeddedness within social-ecological systems at the global scale.
The influence of topography on the global terrestrial water cycle
(Reviews of Geophysics, 2025) Gnann, Sebastian; Baldwin, Jane W.; Cuthbert, Mark O.; Gleeson, Tom; Schwanghart, Wolfgang; Wagener, Thorsten
Topography affects the distribution and movement of water on Earth, yet new insights about topographic controls continue to surprise us and exciting puzzles remain. Here we combine literature review and data synthesis to explore the influence of topography on the global terrestrial water cycle, from the atmosphere down to the groundwater. Above the land surface, topography induces gradients and contrasts in water and energy availability. Long-term precipitation usually increases with elevation in the mid-latitudes, while it peaks at low- to mid-elevations in the tropics. Potential evaporation tends to decrease with elevation in all climate zones. At the land surface, topography is expressed in snow distribution, vegetation zonation, geomorphic landforms, the critical zone, and drainage networks. Evaporation and vegetation activity are often highest at low- to mid-elevations where neither temperature, nor energy availability, nor water availability—often modulated by lateral moisture redistribution—impose strong limitations. Below the land surface, topography drives the movement of groundwater from local to continental scales. In many steep upland regions, groundwater systems are well connected to streams and provide ample baseflow, and streams often start losing water in foothills where bedrock transitions into highly permeable sediment. We conclude by presenting organizing principles, discussing the implications of climate change and human activity, and identifying data needs and knowledge gaps. A defining feature resulting from topography is the presence of gradients and contrasts, whose interactions explain many of the patterns we observe in nature and how they might change in the future.
Rising temperatures drive lower summer minimum flows across hydrologically diverse catchments in British Columbia
(Water Resources Research, 2025) Ruzzante, S. W.; Gleeson, Tom
Excessively low stream flows harm ecosystems and societies, so two key goals of low-flow hydrology are to understand their drivers and to predict their severity and frequency. We show that linear regressions can accomplish both goals across diverse catchments. We analyze 230 unregulated moderate to high relief catchments across rainfall-dominated, hybrid, snowmelt-dominated, and glacial regimes in British Columbia, Canada, with drainage areas spanning 5 orders of magnitude from 0.5 to 55,000 km2. Summer low flows are decreasing in rainfall-dominated and hybrid catchments but have been stable in catchments that remain snowmelt or glacial-dominated. However, we find that since 1950 approximately one third of snowmelt-dominated catchments have transitioned to a hybrid rain-snow regime. The declines in rainfall-dominated and hybrid catchments are dominantly driven by summer precipitation and temperature, and only weakly influenced by winter storage. We apply this understanding to create regression models that predict the minimum summer flow using monthly temperature and precipitation data. These models outperform distributed process-based models for every common goodness-of-fit metric; the performance improvement is mostly a result of abandoning the requirement to simulate all parts of the annual hydrograph. Using these regression models we reconstruct streamflow droughts and low flow anomalies from 1901 to 2022. We reproduce recent drying trends in rainfall-dominated and hybrid catchments, but also show that present conditions are comparable to those seen one hundred years ago. However, anomalously low flows last century were caused by large precipitation deficits while current declines are driven by rising summer temperatures despite near-normal precipitation.
Groundwater resource allocation in British Columbia: Challenges and ways forward
(Confluence: Journal of Watershed Science and Management, 2023) Allen, Diana; Gleeson, Tom
Groundwater allocation in British Columbia is facing several important challenges. Groundwater is licensed under the Water Sustainability Act and potentially included in modern treaties. These challenges include acknowledging the importance of groundwater in supporting environmental flowneeds and human water use, the uncertainty and misconceptions surrounding annual recharge estimates, and the under-appreciated importance of aquifer drainage, while tackling cumulative impacts in watersheds using adaptive management with clear sustainability goals. This article summarizes these challenges and suggests ways forward so that we can more robustly, holistically, and sustainably allocate groundwater resources. This includes some evidenced-based suggestions that are alreadymbeing implemented partially or in some regions. Not implementing these suggestions risks permanent over-allocation of groundwater resources that would impact stream ecology, endanger rural livelihoods, and challenge reconciliation with First Nations. Keywords: groundwater allocation, groundwater resources, water management, water policy, climate change
Groundwater-dependent ecosystem map exposes global dryland protection needs
(Nature, 2024) Rohde, Melissa M.; Albano, Christine M.; Huggins, Xander; Klausmeyer, Kirk R.; Morton, Charles; Sharman, Ali; Zaveri, Esha; Saito, Laurel; Freed, Zach; Howard, Jeanette K.; Job, Nancy; Richter, Holly; Toderich, Kristina; Rodella, Aude-Sophie; Gleeson, Tom; Huntington, Justin; Chandanpurkar, Hrishikesh A.; Purdy, Adam J.; Famiglietti, James S.; Singer, Michael Bliss; Roberts, Dar A.; Caylor, Kelly; Stella, John C.
Groundwater is the most ubiquitous source of liquid freshwater globally, yet its role in supporting diverse ecosystems is rarely acknowledged1,2. However, the location and extent of groundwater-dependent ecosystems (GDEs) are unknown in many geographies, and protection measures are lacking1,3. Here, we map GDEs at high-resolution (roughly 30 m) and find them present on more than one-third of global drylands analysed, including important global biodiversity hotspots4. GDEs are more extensive and contiguous in landscapes dominated by pastoralism with lower rates of groundwater depletion, suggesting that many GDEs are likely to have already been lost due to water and land use practices. Nevertheless, 53% of GDEs exist within regions showing declining groundwater trends, which highlights the urgent need to protect GDEs from the threat of groundwater depletion. However, we found that only 21% of GDEs exist on protected lands or in jurisdictions with sustainable groundwater management policies, invoking a call to action to protect these vital ecosystems. Furthermore, we examine the linkage of GDEs with cultural and socio-economic factors in the Greater Sahel region, where GDEs play an essential role in supporting biodiversity and rural livelihoods, to explore other means for protection of GDEs in politically unstable regions. Our GDE map provides critical information for prioritizing and developing policies and protection mechanisms across various local, regional or international scales to safeguard these important ecosystems and the societies dependent on them.
Uncertainty in model estimates of global groundwater depth
(Environmental Research Letters, 2024) Reinecke, Robert; Gnann, Sebastian; Stein, Lina; Bierkens, Marc; de Graaf, Inge; Gleeson, Tom; Essink, Gualbert Oude; Sutanudjaja, Edwin H; Ruz Vargas, Claudia; Verkaik, Jarno; Wagener, Thorsten
Knowing the depth at which groundwater can be found below the land surface is critical for understanding its potential accessibility by ecosystems and society. Uncertainty in global scale water table depth (WTD) limits our ability to assess groundwater’s role in a water cycle altered by changing climate, land cover, and human water use. Global groundwater models offer a top–down pathway to gain this knowledge, but their uncertainty is currently poorly quantified. Here, we investigate four global groundwater models and reveal steady-state WTD disagreements of more than 100 m for one-third of the global land area. We find that model estimates of land areas with shallow groundwater at <10 m depth vary from 10% to 71% (mean of 23%). This uncertainty directly translates into subsequent assessments, as land areas with potential groundwater accessibility for forests, population, and areas equipped for irrigation, differ substantially depending on the chosen model. We explore reasons for these differences and find that contrary to observations, 3 out of 4 models show deeper water tables in humid than in arid climates and greatly overestimate how strongly topographic slope controls WTD. These results highlight substantial uncertainty associated with any global-scale groundwater analysis, which should be considered and ultimately reduced.
Earth beyond six of nine planetary boundaries
(Science Advances, 2023) Richardson, Katherine; Steffen, Will; Lucht, Wolfgang; Bendtsen, Jørgen; Cornell, Sarah E.; Donges, Jonathan F.; Drüke, Markus; Fetzer, Ingo; Bala, Govindasamy; von Bloh, Werner; Feulner, Georg; Fiedler, Stephanie; Gerten, Dieter; Gleeson, Tom; Hofmann, Matthias; Huiskamp, Willem; Kummu, Matti; Mohan, Chinchu; Nogués-Bravo, David; Petri, Stefan; Porkka, Miina; Rahmstorf, Stefan; Schaphoff, Sibyll; Thonicke, Kirsten; Tobian, Arne; Virkki, Vili; Wang-Erlandsson, Lan; Weber, Lisa; Rockström, Johan
This planetary boundaries framework update finds that six of the nine boundaries are transgressed, suggesting that Earth is now well outside of the safe operating space for humanity. Ocean acidification is close to being breached, while aerosol loading regionally exceeds the boundary. Stratospheric ozone levels have slightly recovered. The transgression level has increased for all boundaries earlier identified as overstepped. As primary production drives Earth system biosphere functions, human appropriation of net primary production is proposed as a control variable for functional biosphere integrity. This boundary is also transgressed. Earth system modeling of different levels of the transgression of the climate and land system change boundaries illustrates that these anthropogenic impacts on Earth system must be considered in a systemic context.
Groundwater connections and sustainability in social-ecological systems
(Groundwater, 2023) Huggins, Xander; Gleeson, Tom; Castilla-Rho, Juan; Holley, Cameron; Re, Viviana; Famiglietti, James S.
Groundwater resources are connected with social, economic, ecological, and Earth systems. We introduce the framing of groundwater-connected systems to better represent the nature and complexity of these connections in data collection, scientific investigations, governance and management approaches, and groundwater education. Groundwater-connected systems are social, economic, ecological, and Earth systems that interact with groundwater, such as irrigated agriculture, groundwater-dependent ecosystems, and cultural relationships to groundwater expressions such as springs and rivers. Groundwater-connected systems form social-ecological systems with complex behaviors such as feedbacks, nonlinear processes, multiple stable system states, and path dependency. These complex behaviors are only visible through this integrated system framing and are not endogenous properties of physical groundwater systems. The framing is syncretic as it aims to provide a common conceptual foundation for the growing disciplines of socio-hydrogeology, eco-hydrogeology, groundwater governance, and hydro-social groundwater analysis. The framing also facilitates greater alignment between the groundwater sustainability discourse and emerging sustainability concepts and principles. Aligning with these concepts and principles presents groundwater sustainability as more than a physical state to be reached; and argues that place-based and multifaceted goals, values, justice, knowledge systems, governance, and management must continually be integrated to maintain groundwater's social, ecological, and Earth system functions. The groundwater-connected systems framing can underpin a broad, methodologically pluralistic, and community-driven new wave of data collection and analysis, research, governance, management, and education. These developments, together, can invigorate efforts to foster sustainable groundwater futures in the complex systems groundwater is embedded within.
Defining renewable groundwater use and its relevance to sustainable groundwater management
(Water Resources Research, 2023) Cuthbert, M. O.; Gleeson, Tom; Bierkens, M. F. P.; Ferguson, G.; Taylor, R. G.
Groundwater systems are commonly defined as renewable or non-renewable based on natural fluxes of recharge or on estimates of aquifer storage and groundwater residence time. However, we show here that the principle of capture (i.e., how recharge and discharge change due to pumping) challenges simple definitions so that a groundwater system cannot be renewable or non-renewable in and of itself, but only with reference to how the groundwater is being used. We develop and propose more hydraulically informed definitions for flux-renewable and storage-renewable groundwater use, and a combined definition that encompasses both the flux-based and storage-based perspectives such that: renewable groundwater use allows for dynamically stable re-equilibrium of groundwater levels and quality on human timescales. Further, we show how a matrix of combinations of (a) the ratio of pumping rate to the maximum rate of capture along with (b) the response or recovery timescales implicit in this definition, leads to a useful four-quadrant framework for characterizing groundwater use, illustrated using case studies from aquifers around the world. Renewable groundwater use may inform pathways to groundwater sustainability, which encompasses a broader set of dimensions (e.g., socio-political, economic, ecological and cultural) beyond the scope of groundwater science. We propose that separating physically robust definitions of renewable groundwater use from the inherently value-based language of sustainability, can help bring much needed clarity to wider discussions about sustainable groundwater management strategies, and the role of groundwater science and scientists in such endeavors.
Notable shifts beyond pre-industrial streamflow and soil moisture conditions transgress the planetary boundary for freshwater change
(Nature Water, 2024) Porkka, Miina; Virkki, Vili; Wang-Erlandsson, Lan; Gerten, Dieter; Gleeson, Tom; Mohan, Chinchu; Fetzer, Ingo; Jaramillo, Fernando; Staal, Arie; te Wierik, Sofie; Tobian, Arne; van der Ent, Ruud; Döll, Petra; Flörke, Martina; Gosling, Simon N.; Hanasaki, Naota; Satoh, Yusuke; Müller Schmied, Hannes; Wanders, Niko; Famiglietti, James S.; Rockström, Johan; Kummu, Matti
Human actions compromise the many life-supporting functions provided by the freshwater cycle. Yet, scientific understanding of anthropogenic freshwater change and its long-term evolution is limited. Here, using a multi-model ensemble of global hydrological models, we estimate how, over a 145-year industrial period (1861–2005), streamflow and soil moisture have deviated from pre-industrial baseline conditions (defined by 5th–95th percentiles, at 0.5° grid level and monthly timestep over 1661–1860). Comparing the two periods, we find an increased frequency of local deviations on ~45% of land area, mainly in regions under heavy direct or indirect human pressures. To estimate humanity’s aggregate impact on these two important elements of the freshwater cycle, we present the evolution of deviation occurrence at regional to global scales. Annually, local streamflow and soil moisture deviations now occur on 18.2% and 15.8% of global land area, respectively, which is 8.0 and 4.7 percentage points beyond the ~3 percentage point wide pre-industrial variability envelope. Our results signify a substantial shift from pre-industrial streamflow and soil moisture reference conditions to persistently increasing change. This indicates a transgression of the new planetary boundary for freshwater change, which is defined and quantified using our approach, calling for urgent actions to reduce human disturbance of the freshwater cycle.
Global water cycle shifts far beyond pre-industrial conditions – planetary boundary for freshwater change transgressed
(EarthArXiv, 2022) Porkka, Miina; Virkki, Vili; Wang-Erlandsson, Lan; Gerten, Dieter; Gleeson, Tom; Mohan, Chinchu; Fetzer, Ingo; Jaramillo, Fernando; Staal, Arie; Wierik, Sofie te; Tobian, Arne; Ent, Ruud van der; Döll, Petra; Flörke, Martina; Gosling, Simon; Hanasaki, Naota; Satoh, Yusuke; Schmied, Hannes Müller; Wanders, Niko; Rockstrom, Johan; Kummu, Matti
Human actions compromise the many life-supporting functions provided by the freshwater cycle. Yet, scientific understanding of anthropogenic freshwater change and its long-term evolution is limited. Using a multi-model ensemble of global hydrological models, we estimate how, over a 145-year industrial period, streamflow and soil moisture have deviated from pre-industrial baseline conditions (defined by 5th–95th percentiles, at 0.5° grid level and monthly time step). We find increased frequency of local deviations on ~45% of land area, mainly in regions under heavy direct or indirect human pressures. To estimate humanity’s aggregate impact on the freshwater cycle, we present the evolution of deviation occurrence at regional to global scales. Currently, local streamflow and soil moisture deviations occur on 18.2% and 15.8% of global land area, respectively, which is 8.0 and 4.7 percentage points beyond the ~3 percentage point wide pre-industrial variability envelope. Finally, we discuss applying our approach to define a planetary boundary for freshwater change. Our results indicate a substantial shift from stable pre-industrial streamflow and soil moisture conditions to persistently increasing change and a transgression of the freshwater change planetary boundary, calling for urgent actions to reduce human disturbance of the freshwater cycle.

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