Hydrology

  • Article
    | Open Access

    Changes in climatology and perturbation will lead to different impacts on regional climate change, but their effect remains a subject of debate. Here the authors develop a new downscaling procedure that reveals the importance of both changes on the regional climate and examines their nonlinear effect.

    • Sachiho A. Adachi
    • , Seiya Nishizawa
    •  & Hirofumi Tomita
  • Article
    | Open Access

    Human and environmental water needs can come into conflict in dam-regulated river systems. Here, Chen and Olden investigate the potential for the use of fish–flow modeling to make recommendations for the management of native and nonnative fish species whilst providing water for society.

    • William Chen
    •  & Julian D. Olden
  • Article
    | Open Access

    Current global-scale nitrogen (N) budgets quantifying anthropogenic impacts on the N cycle do not explicitly consider nitrate storage in the vadose zone. Here, using estimates of depth to groundwater and nitrate leaching between 1900–2000, the authors show that the vadose zone is an important store of nitrate.

    • M. J. Ascott
    • , D. C. Gooddy
    •  & A. M. Binley
  • Article
    | Open Access

    In the Gale Crater on Mars, organic matter has been detected, but in much lower concentrations than expected. Here, the authors conduct clay mineral synthesis experiments which suggest that clay minerals may rapidly form under oxidized conditions and thus explain the low organic concentrations in Gale Crater.

    • Seth R. Gainey
    • , Elisabeth M. Hausrath
    •  & Courtney L. Bartlett
  • Article
    | Open Access

    Downslope sediment transport on Mars is reported, but the transport capacity of unstable water under low pressures is not well understood. Here, the authors present a newly discovered, highly reactive transportation mechanism that is only possible under low pressure environments.

    • Jan Raack
    • , Susan J. Conway
    •  & Manish R. Patel
  • Article
    | Open Access

    Cool roofs have been shown to mitigate heat in urban areas, but their impact on water conservation has not been examined. Here the authors conduct simulations with an urban canopy model to show that implementation of cool roofs in California can also reduce outdoor water consumption by up to 9%.

    • Pouya Vahmani
    •  & Andrew D. Jones
  • Article
    | Open Access

    Climate models repeatedly show a warm and dry bias over the central United States, but the origin of this bias remains unclear. Here the authors associate this bias to precipitation deficits in models and after applying a correction, projected precipitation in this region shows no significant changes.

    • Yanluan Lin
    • , Wenhao Dong
    •  & Yong Luo
  • Article
    | Open Access

    Globally diarrheal disease through contaminated water sources is a major cause of child mortality. Here, the authors compile a database of 293,362 children in 35 countries and find that upstream tree cover is linked to a lower probability of diarrheal disease and that increasing tree cover may lower mortality.

    • Diego Herrera
    • , Alicia Ellis
    •  & Taylor H. Ricketts
  • Article
    | Open Access

    Against the backdrop of a declining monsoon, the number of extreme rain events is on the rise over central India. Here the authors identify a threefold increase in widespread extreme rains over the region during 1950–2015, driven by an increasing variability of the low-level westerlies over the Arabian Sea.

    • M. K. Roxy
    • , Subimal Ghosh
    •  & M. Rajeevan
  • Article
    | Open Access

    The evaporation of water represents an alternative source of renewable energy. Building on previous models of evaporation, Cavusoglu et al. show that the power available from this natural resource is comparable to wind and solar power, yet it does not suffer as much from varying weather conditions.

    • Ahmet-Hamdi Cavusoglu
    • , Xi Chen
    •  & Ozgur Sahin
  • Article
    | Open Access

    Earth system model simulations of future climate in the Amazon show little agreement. Here, the authors show that biases in internally generated climate explain most of this uncertainty and that the balance between water-saturated and water-limited evapotranspiration controls the Amazon resilience to climate change.

    • Anders Ahlström
    • , Josep G. Canadell
    •  & Robert B. Jackson
  • Article
    | Open Access

    The impact of climate change on phosphorus (P) loss from land to water is unclear. Here, the authors use P flux data, climate simulations and P transfer models to show that only large scale agricultural change will limit the effect of climate change on average winter P loads in three catchments across the UK.

    • M. C. Ockenden
    • , M. J. Hollaway
    •  & P. M. Haygarth
  • Article
    | Open Access

    The response of the coupled carbon and water cycles to anthropogenic climate change is unclear. Here, the authors show that terrestrial carbon uptake increased significantly from 1982 to 2011 and that this increase is largely driven by increased water-use efficiency, rather than an increase in water use.

    • Lei Cheng
    • , Lu Zhang
    •  & Yongqiang Zhang
  • Article
    | Open Access

    Global warming and hydropower regulations are major threats to future fresh-water availability and biodiversity. Here, the authors show that their impact on flow regime over a large landmass result in similar changes, but hydropower is more critical locally and may have potential for climate adaptation in floodplains.

    • B. Arheimer
    • , C. Donnelly
    •  & G. Lindström
  • Article
    | Open Access

    The sensitivity of global precipitation to warming is largely governed by changes in atmospheric longwave radiation, a function of cloud cover. Here the authors show that tightening of the tropical circulation with warming drives a decrease in high cloud cover, resulting in higher precipitation changes.

    • Hui Su
    • , Jonathan H. Jiang
    •  & Yuk L. Yung
  • Article
    | Open Access

    Rivers provide a major pathway for ocean plastic waste, but effective mitigation is dependent on a quantification of active sources. Here, the authors present a global model of riverine plastic inputs, and estimate annual plastic waste of almost 2.5 million tonnes, with 86% sourced from Asia.

    • Laurent C. M. Lebreton
    • , Joost van der Zwet
    •  & Julia Reisser
  • Article
    | Open Access

    Water is a fundamental resource, but its role in hominin evolution is not well explored. Here, the authors use a combination of groundwater, climate and agent-based models to show that groundwater availability may be critical to past patterns of taxonomic diversity in hominin development in East Africa.

    • M. O. Cuthbert
    • , T. Gleeson
    •  & G. M. Ashley
  • Article
    | Open Access

    El Niño events in the Central Pacific may be changing due to climate change, but long records to support this are lacking. Here, the authors present sea surface temperature reconstructions from tree cellulose for the last 800 years which suggest the variability of Central Pacific El Niño events has increased.

    • Yu Liu
    • , Kim M. Cobb
    •  & Hans W. Linderholm
  • Article
    | Open Access

    Mountain snowpack in the western United States has declined over the past three decades. Fyfeet al. show that this trend cannot be explained by natural variability alone and show that under a business-as-usual scenario a further loss of up to 60% in mountain snowpack is projected in the coming three decades.

    • John C. Fyfe
    • , Chris Derksen
    •  & Yanjun Jiao
  • Article
    | Open Access

    El Niño and La Niña (ENSO) events influence global river flow and are often used as an early indicator of potential flooding. Here, the authors show that the probability of ENSO-driven flood hazard is more complex than is often perceived, and highlight the importance of considering hydrological response.

    • R. Emerton
    • , H. L. Cloke
    •  & F. Pappenberger
  • Article
    | Open Access

    Bioaerosols may be generated when bubbles break on the surface of water, but it is unclear if this mechanism works with soil-based microbes. Here, the authors show that soil bacteria may be transferred from the soil surface and dispersed by raindrops.

    • Young Soo Joung
    • , Zhifei Ge
    •  & Cullen R. Buie
  • Article
    | Open Access

    Point measurements have historically been used to assess salt marsh vulnerability; however, these metrics do not integrate over the necessary spatiotemporal scales. Here, the authors show that two geomorphic-based, spatiotemporally integrative metrics reveal vulnerability not captured by traditional metrics.

    • Neil K. Ganju
    • , Zafer Defne
    •  & Luca Carniello
  • Article
    | Open Access

    Forests impact continental-scale moisture recycling, but their impact on regional-scale cloud cover is little known. Here, using satellite observations, Teulinget al. illustrate enhanced cloud cover over regional forested areas in western Europe due to the establishment of a forest-breeze circulation.

    • Adriaan J. Teuling
    • , Christopher M. Taylor
    •  & Jordi Vilà-Guerau de Arellano
  • Article
    | Open Access

    Surface meltwater draining to the bed of the Greenland Ice Sheet each summer causes ice flow changes inconsistent with the prevailing theory of channelizing subglacial drainage. Here, the authors show this is caused by limited, gradual leakage of water from previously ignored weakly connected regions of the bed.

    • Matthew J. Hoffman
    • , Lauren C. Andrews
    •  & Blaine Morriss
  • Article
    | Open Access

    Lakes play a key role in our ecosystems and thus it is vital to understand their distribution and volume. Here, the authors present a new global lake database (HydroLAKES) and develop a new geo-statistical model to show global lake area, shoreline length, water volume and hydraulic residence times.

    • Mathis Loïc Messager
    • , Bernhard Lehner
    •  & Oliver Schmitt
  • Article
    | Open Access

    Megacities rely on groundwater from aquifers that may be over-exploited and be at risk of contamination. Khan et al. evaluate the complex aquifers supplying Dhaka, Bangladesh and show that extensive groundwater pumping could lead to unpredictable future arsenic contamination in deep aquifers outside the city.

    • Mahfuzur R. Khan
    • , Mohammad Koneshloo
    •  & Holly A. Michael
  • Article
    | Open Access

    Recent samples have shown that the Moon's interior, previously thought to be anhydrous, contains water, yet how this water was delivered is unclear. Here, using isotopic analyses and modelling, Barnes et al. show that carbonaceous chondrite-type objects delivered >80% of the Moon's bulk water.

    • Jessica J. Barnes
    • , David A. Kring
    •  & Sara S. Russell
  • Article |

    The effects of forests on water yield are uncertain, with some studies indicating that increased evapotranspiration reduces water yield and other showing that forests increase it. Here, the authors analyse published data to settle this debate, finding that afforestation has a positive effect on water yield.

    • Guoyi Zhou
    • , Xiaohua Wei
    •  & Yongxian Su
  • Article
    | Open Access

    Extreme winter flooding has caused devastation across Europe in recent years, highlighting the need for improved forecasts. Here, the authors show that the use of water vapour transport, rather than precipitation in weather prediction models, can extend the forecast horizon by as much as 3 days.

    • David A. Lavers
    • , Florian Pappenberger
    •  & Ervin Zsoter
  • Article |

    The delivery of meltwater to the base of the Greenland Ice Sheet has been shown to regulate ice flow, yet the role of soft basal sediment is unknown. Here, the authors use a three-dimensional ice sheet model to assess the impact of seasonal meltwater delivery on subglacial sediment shear strength and ice flow.

    • M. Bougamont
    • , P. Christoffersen
    •  & S. P. Carter
  • Article |

    Lakes play an important role in the global carbon cycle and understanding their organic matter cycling is vital. Kellerman et al.apply an ultrahigh-resolution technique to 120 lakes across Sweden and show that the molecular composition is shaped by water dynamics and temperature.

    • Anne M. Kellerman
    • , Thorsten Dittmar
    •  & Lars J. Tranvik
  • Article |

    The long-term hydroclimate variability in Amazonia and its influence on biodiversity remain poorly understood. Here, new speleothem oxygen isotope records characterize spatial–temporal changes in precipitation and provide new insights to understanding the west–east contrasting pattern of biodiversity in Amazonia.

    • Hai Cheng
    • , Ashish Sinha
    •  & Augusto S. Auler
  • Article |

    Global vegetation models are too coarse to predict climate change effects at the hillslope level. Using high-resolution LiDAR, the authors explore the three-dimensional structure and vegetation of an African savanna, and suggest that finer hydrogeomorphological features will shape future climate effects.

    • Shaun R. Levick
    • , Gregory P. Asner
    •  & David E. Knapp