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Results for “Hydrology Research”

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At least 847 records · Page 47Linked to original sources
USGS2018

Hydrologic performance of retrofit rain gardens in a residential neighborhood (Cleveland Ohio USA) with a focus on monitoring methods

Green infrastructure refers to a range of urban stormwater management tools that can be flexibly implemented. These practices can aid in mitigating the negative impacts of runoff by increasing catchment detention capacity. We studied two engineered rain gardens (Cleveland OH) that were designed to infiltrate and detain direct runoff volume generated from an adjacent roadway, and sheet flow from pervious areas of each catchment area. We also accounted for hydrologic interactions between the engineered and upslope basic (non-engineered) rain gardens. A whole water-cycle monitoring approach was employed to fully assess the role of green infrastructure interventions on performance as inflows captured, duration of outflow drainage (i.e., excess moisture), hydrologic losses (e.g., evapotranspiration), and groundwater table dynamics. We found that these tandem rain gardens had good capacity for runoff inflow volumes over the course of over 100 storm events.The integration of green infrastructure in urban landscapes and long-term monitoring for effectiveness and its key functions produces novel data that can be used by researchers and other interested parties to conduct assessments of urban ecosystem functions and leverage these unique datasets by integrating with other datasets as per good scientific practice. We role model good monitoring practice, discuss unique ways to interpret challenging hydraulic circumstances, and conclude with a discussion of monitoring techniques that scale between the simple, passive and elegant; to full-blown research-grade monitoring infrastructure such as that employed in this study.

Ohio↗
USGS2002

The role of bedrock topography on subsurface storm flow

We conducted a detailed study of subsurface flow and water table response coupled with digital terrain analysis (DTA) of surface and subsurface features at the hillslope scale in Panola Mountain Research Watershed (PMRW), Georgia. Subsurface storm flow contributions of macropore and matrix flow in different sections along an artificial trench face were highly variable in terms of timing, peak flow, recession characteristics, and total flow volume. The trench flow characteristics showed linkages with the spatial tensiometer response defining water table development upslope. DTA of the ground surface did not capture the observed spatial patterns of trench flow or tensiometric response. However, bedrock surface topographic indices significantly improved the estimation of spatial variation of flow at the trench. Point‐scale tensiometric data were also more highly correlated with the bedrock surface‐based indices. These relationships were further assessed for temporal changes throughout a rainstorm. Linkages between the bedrock indices and the trench flow and spatial water table responses improved during the wetter periods of the rainstorm, when the hillslope became more hydrologically connected. Our results clearly demonstrate that in developing a conceptual framework for understanding the mechanisms of runoff generation, local bedrock topography may be highly significant at the hillslope scale in some catchments where the bedrock surface acts as a relatively impermeable boundary.

Water Resources Research↗
USGS2014

Hyporheic flow and transport processes: mechanisms, models, and biogeochemical implications

Fifty years of hyporheic zone research have shown the important role played by the hyporheic zone as an interface between groundwater and surface waters. However, it is only in the last two decades that what began as an empirical science has become a mechanistic science devoted to modeling studies of the complex fluid dynamical and biogeochemical mechanisms occurring in the hyporheic zone. These efforts have led to the picture of surface-subsurface water interactions as regulators of the form and function of fluvial ecosystems. Rather than being isolated systems, surface water bodies continuously interact with the subsurface. Exploration of hyporheic zone processes has led to a new appreciation of their wide reaching consequences for water quality and stream ecology. Modern research aims toward a unified approach, in which processes occurring in the hyporheic zone are key elements for the appreciation, management, and restoration of the whole river environment. In this unifying context, this review summarizes results from modeling studies and field observations about flow and transport processes in the hyporheic zone and describes the theories proposed in hydrology and fluid dynamics developed to quantitatively model and predict the hyporheic transport of water, heat, and dissolved and suspended compounds from sediment grain scale up to the watershed scale. The implications of these processes for stream biogeochemistry and ecology are also discussed."

Reviews of Geophysics↗
USGS2009

Water balance dynamics in the Nile Basin

Understanding the temporal and spatial dynamics of key water balance components of the Nile River will provide important information for the management of its water resources. This study used satellite-derived rainfall and other key weather variables derived from the Global Data Assimilation System to estimate and map the distribution of rainfall, actual evapotranspiration (ETa), and runoff. Daily water balance components were modelled in a grid-cell environment at 0·1 degree (∼10 km) spatial resolution for 7 years from 2001 through 2007. Annual maps of the key water balance components and derived variables such as runoff and ETa as a percent of rainfall were produced. Generally, the spatial patterns of rainfall and ETa indicate high values in the upstream watersheds (Uganda, southern Sudan, and southwestern Ethiopia) and low values in the downstream watersheds. However, runoff as a percent of rainfall is much higher in the Ethiopian highlands around the Blue Nile subwatershed. The analysis also showed the possible impact of land degradation in the Ethiopian highlands in reducing ETa magnitudes despite the availability of sufficient rainfall. Although the model estimates require field validation for the different subwatersheds, the runoff volume estimate for the Blue Nile subwatershed is within 7·0% of a figure reported from an earlier study. Further research is required for a thorough validation of the results and their integration with ecohydrologic models for better management of water and land resources in the various Nile Basin ecosystems.

Hydrological Processes↗
USGS1999

7Be as a tracer of flood sedimentation on the northern California continental margin

Sediment inventories of the cosmogenic radionuclide 7 Be (t 1/2 =53 d) were measured on the Eel River shelf and slope (northern California continental margin) to investigate sedimentation processes associated with coastal river flooding. Seabed coring shortly after major riverflow events in 1995 and 1997 documented a shelf-wide flood deposit, and subsequent radionuclide studies determined 7 Be to be a powerful tracer of fine-grained river sediment. In addition, distinctive signatures of 234 Th and 210 Pb were observed in oceanic flood deposits and provided additional information regarding depositional processes. During the 1995–1997 monitoring period, 7 Be was present (2–35 dpm cm -2 ) in shelf and slope sediments only after periods of high rainfall and river runoff during the winter months. It is suggested that fluvial input was the primary source of 7 Be in shelf sediments after the floods. 7 Be sediment inventories and sediment-trap fluxes determined after the 1997 flood revealed that fine-grained fluvial sediments were rapidly (within one month) broadcast over the continental margin, to the 500 m isobath. Dispersal was apparently facilitated by energetic storm waves, which resuspended and redistributed some fraction of the suspended load residing on the shelf prior to accretion as flood deposits. These observations illustrate that floods are an important sedimentary process for modern environments of the Eel shelf and slope, and perhaps for other fluviomarine sedimentary systems of the northern California continental margin. Ratios of the 210 Pb sediment-accumulation rate (100 yr average) to the 7 Be deposition rate (1–2 month average) for shelf sites illustrate the episodic nature of shelf sedimentation, and suggest that a minimum of 3–30 depositional events complete the most recent stratigraphic record. This observation is consistent with the magnetude and frequency of fluvial sediment input, as Eel River floods with return periods of 3–33 yr (3% of the time of record) have supplied >80% of the total 85 yr suspended load. Based on radionuclide and hydrologic data, it can be concluded that a small number of flood depositional events have had a disproportionate impact on the sedimentary record of the Eel shelf.

California↗
USGS2009

Investigation of aquifer-estuary interaction using wavelet analysis of fiber-optic temperature data

Fiber-optic distributed temperature sensing (FODTS) provides sub-minute temporal and meter-scale spatial resolution over kilometer-long cables. Compared to conventional thermistor or thermocouple-based technologies, which measure temperature at discrete (and commonly sparse) locations, FODTS offers nearly continuous spatial coverage, thus providing hydrologic information at spatiotemporal scales previously impossible. Large and information-rich FODTS datasets, however, pose challenges for data exploration and analysis. To date, FODTS analyses have focused on time-series variance as the means to discriminate between hydrologic phenomena. Here, we demonstrate the continuous wavelet transform (CWT) and cross-wavelet transform (XWT) to analyze FODTS in the context of related hydrologic time series. We apply the CWT and XWT to data from Waquoit Bay, Massachusetts to identify the location and timing of tidal pumping of submarine groundwater.

Geophysical Research Letters↗
USGS2010

The effect of streambed topography on surface-subsurface water exchange in mountain catchments

A numerical hydrological simulation suggested that water exchange between stream channels and adjacent aquifers is enhanced by convexities and concavities in streambed topography. At St. Kevin Gulch, an effluent stream in the Rocky Mountains of Colorado, subsurface hydraulic gradients and movement of ionic tracers indicated that stream water was locally recharged into well-defined flow paths through the alluvium. Stream water-filled flow paths in the alluvium (referred to as substream flow paths) returned to the stream a short distance downstream (1 to 10 m). Recharge to the substream flow paths occurred where stream water slope increased, at the transition from pools (<1%) to steeper channel units (5–20%). Return of substream flow paths to the stream occurred where stream water slope decreased, at the transition from steeper channel units to pools. A net water flux calculation is typically used to characterize water and solute fluxes between surface and subsurface zones of catchments. Along our study reach at St. Kevin Gulch the net inflow of water from subsurface to stream (1.6 mL s −1 m −1 ) underestimated the gross inflow (2.7 mL s −1 m −1 ) by 40%. The influence of streambed topography is to enhance hydrological fluxes between stream water and subsurface zones and to prolong water-sediment contact times; these effects could have important consequences for solute transport, retention, and transformation in catchments.

Water Resources Research↗
USGS2013

Controls on ecosystem and root respiration across a permafrost and wetland gradient in interior Alaska

Permafrost is common to many northern wetlands given the insulation of thick organic soil layers, although soil saturation in wetlands can lead to warmer soils and increased thaw depth. We analyzed five years of soil CO 2 fluxes along a wetland gradient that varied in permafrost and soil moisture conditions. We predicted that communities with permafrost would have reduced ecosystem respiration (ER) but greater temperature sensitivity than communities without permafrost. These predictions were partially supported. The colder communities underlain by shallow permafrost had lower ecosystem respiration (ER) than communities with greater active layer thickness. However, the apparent Q 10 of monthly averaged ER was similar in most of the vegetation communities except the rich fen, which had smaller Q 10 values. Across the gradient there was a negative relationship between water table position and apparent Q 10 , showing that ER was more temperature sensitive under drier soil conditions. We explored whether root respiration could account for differences in ER between two adjacent communities (sedge marsh and rich fen), which corresponded to the highest and lowest ER, respectively. Despite differences in root respiration rates, roots contributed equally (~40%) to ER in both communities. Also, despite similar plant biomass, ER in the rich fen was positively related to root biomass, while ER in the sedge marsh appeared to be related more to vascular green area. Our results suggest that ER across this wetland gradient was temperature-limited, until conditions became so wet that respiration became oxygen-limited and influenced less by temperature. But even in sites with similar hydrology and thaw depth, ER varied significantly likely based on factors such as soil redox status and vegetation composition.

Alaska↗
USGS2024

Investigating the atmospheric conditions associated with impactful shallow landslides in California (USA)

Shallow landslides are often triggered during rainfall events, which can increase subsurface soil water pressure and destabilize hillslopes. The likelihood of regional shallow landslide initiation is often assessed through a comparison of rainfall intensity and duration to pre-established thresholds. While informative for landslide warning, this exclusive focus on rainfall exceeding thresholds does not consider the meteorological conditions producing the rainfall. Here, we ask the question, are there common meteorological characteristics that lead to landslide-triggering precipitation? We develop a catalog of 18 post-1995 widespread, impactful shallow landslide events occurring within 13 storms across California, USA, where initiation time could be constrained to a ≤6-h window. We examine storm characteristics during the landslide initiation window using atmospheric reanalysis products, radar observations, and quantitative precipitation estimates. We find that, while there are some common atmospheric characteristics across landslide events, they can occur under a range of atmospheric conditions. For example, all Northern California landslide events assessed are associated with moderate to strong atmospheric rivers (ARs), while Southern California landslides feature non-AR to strong AR conditions. The storm events evaluated herein share many characteristics of hydrologically important storms in California that did not necessarily result in landslides; thus, atmospheric characteristics alone may not be sufficient to determine whether landslides will occur. However, documenting the characteristics of landslide-triggering storms defines the conditions under which landslides tend to occur, provides analog events that can be useful in forecast applications, helps define future research directions relating to atmospheric conditions and landslides, and supports interdisciplinary research efforts.

California↗
USGS1997

Complex response of a midcontinent north America drainage system to late Wisconsinan sedimentation

The geomorphic evolution of Mud Creek basin in eastern Iowa, U.S.A. serves to illustrate how geomorphic influences such as sediment supply, valley gradient, climate, and vegetation are recorded in the alluvial stratigraphic record. Sediment supply to the fluvial system increased significantly during the late Wisconsinan through a combination of periglacial erosion and loess accumulation. Subsequent evolution of the Holocene alluvial stratigraphic record reflects long-term routing of the late Wisconsinan sediment through the drainage basin in a series of cut-and-fill cycles whose timing was influenced by hydrologic response to change in climate and vegetation. When viewed in a regional context, the alluvial stratigraphic record appears to reflect a long-term complex response of the fluvial system to increased sediment supply during the late Wisconsinan. Hydrologic and sediment-supply changes accompanying the spread of Euroamerican agriculture to the basin in the 1800s dramatically upset trends in sedimentation and channel behavior established during the Holocene.

Journal of Sedimentary Research↗
USGS2023

Assessment of riparian vegetation patterns and change downstream from Glen Canyon Dam from 2014 to 2019

Changes in riparian vegetation cover and composition occur in relation to flow regime, geomorphic template, and climate, and can have cascading effects on aquatic and terrestrial ecosystems. Tracking such changes over time is therefore an important part of monitoring the condition and trajectory of riparian ecosystems. Maintaining diverse, self-sustaining riparian vegetation comprised of mostly native species is identified in the Glen Canyon Dam Long-Term Experimental and Management Plan as a key resource objective for the section of the Colorado River between Glen Canyon Dam and Lake Mead. The U.S. Geological Survey Grand Canyon Monitoring and Research Center implemented an annual monitoring program in 2014 to assess the status and trends of riparian vegetation along this section of river, particularly as they relate to flow regime. In this report, we summarize plant species composition and cover data collected under the annual monitoring program from 2014 to 2019, with special consideration given to the hydrologic position, associated geomorphic feature class, local climate patterns, native and nonnative species, and floristic region for key vegetation metrics and species. We divided the study area into four river segments (referred to as Glen Canyon, Marble Canyon, eastern Grand Canyon, and western Grand Canyon) on the basis of geography and floristic composition and calculated each recorded plant species’ relative frequency and foliar cover by river segment. These data were then used to evaluate species composition relationships among river segments, hydrologic zones, geomorphic features, and sampling years through ordination analysis. Temporal trends in our focal resource objectives—species richness, total foliar cover, proportion of native to nonnative species richness, proportion of native to nonnative species cover, Tamarix cover, Pluchea sericea cover, and Baccharis species cover—were assessed using mixed-effects models. Four patterns related to species composition emerged: (1) species composition of fixed-site sandbars differed from that of randomly selected sites (including randomly selected sandbars), (2) species composition of Glen Canyon sites differed from that of other previously identified floristic regions, (3) species composition differed across hydrologic zones related to dam operations, and (4) species composition within river segments did not change across years. For temporal patterns, four main findings emerged: (1) trends differed between fixed-sites and randomly selected sites; (2) although few directional changes were observed from 2014 to 2019, Baccharis species cover increased at randomly selected sites in areas influenced by daily water fluctuations; (3) native species cover and richness were greater than nonnative species cover and richness across all hydrologic zones; and (4) the temporal trend metrics used here can be used across floristic groups, enabling assessment of the Colorado River ecosystem as a whole. In addition to these findings, lists of recorded plant species are included as appendixes. The variations and patterns in vegetation status and trends presented in this report can be used as a baseline against which future monitoring can be compared.

Arizona↗
USGS1995

Preliminary analysis of down-core biotic assemblages Bob Allen Keys, Everglades National Park, Florida Bay

Introduction A series of short piston cores (< 2m) were taken from eleven stations in Florida Bay in May, 1994 by researchers from the U.S. Geological Survey (St. Petersburg, FL., Woods Hole, MA., and Denver CO.) in cooperation with South Florida Water Management District, and the Everglades National Park, and the National Oceanic and Atmospheric Administration (NOAA). Core 6A from Bob Allen Keys (25° 1.391” N, 80°39.41” W) penetrated 172 cm of Holocene sediments in 0.6 m of water on a grass covered mud bank, approximately 1.75 miles (2.82 km) east of the water monitoring station on the southern end of the Bob Allen Keys. Core 6A was sampled for particle size, insoluble residue, water content, loss on ignition, Pb 210 , Rasup>222, and paleontologic analyses. Here we present the results of the preliminary paleontologic analyses of the biotic components from core #6A. The Everglades/Florida Bay ecosystem has formed over the last 5000 years at the southern tip of peninsular Florida. Here it has been influenced by Atlantic, Caribbean and Gulf of Mexico waters, and by tropical and subtropical climatic regimes. This location ensures that over time the ecosystem has undergone climatic changes on both a seasonal and long term basis, and that it has been subjected to many major storms. Additionally, in the last century, the hydrologic regime of the region has been altered profoundly through construction of a canal system to control flooding in southern Florida. This system regulates the timing and amount of freshwater flow into Florida Bay. Recently, algal blooms, seagrass, and sponge die-offs, and declining numbers of shellfish, have been reported in Florida Bay; although it has been assumed that these changes have resulted from human alteration of freshwater flow into the bay, this assumption has not been rigorously tested. The research described here is part of a project designed to examine the history of the Everglades/Florida Bay ecosystem over the last 150 years and to test assumptions of cause and effect. The purpose of the project is two-fold; first, to determine the characteristics of the ecosystem prior to significant human-induced alteration, including the natural range of variation in the ecosystem. This information will establish a baseline for restoration of the system. Second, the project aims to establish the extent, range, and timing of changes to the ecosystem over the last 150 years, and to determine whether these changes correlate with human alteration of the environment, or meteorological patterns, such as precipitation and major storms, or a combination of factors.

Florida↗
USGS2018

Biocrusts: The living skin of the Earth

Biological soil crusts (biocrusts) form a “living skin” at the soil surface in many low productivity ecosystems around the world including water- and cold-limited environments, and early successional seres (Belnap et al. 2003). They may be composed of any configuration of soil surface-dwelling cyanobacteria, eukaryotic algae, lichens, mosses or liverworts, and support assemblages of decomposers and a faunal food web (Belnap et al. 2003). These soil surface communities have global relevance, as it has been recently estimated that they cover about 12% of the terrestrial surface currently (Rodriguez-Caballero et al. 2018). Biocrust communities are perhaps an ideal subject for the journal Plant and Soil, because they are simultaneously plant-like, due to their dominance by autotrophs, yet biocrusts are also clearly a physical feature of the soil given that component organisms are enmeshed in, adherent to, or otherwise in direct contact with the soil surface. The activity of the organisms is what engineers the well-aggregated thin layer at the soil surface that we recognize as a biocrust (Belnap et al. 2003). The contributions of biocrusts to ecosystem function has fueled much research interest, initially in the observation of biocrusts’ soil aggregating and erosion-resisting nature, and later as a multifunctional, globally-relevant ecosystem element instrumental in: 1. building or otherwise altering soil nutrient stocks through N-fixation (Elbert et al. 2012), dust trapping (Reynolds et al. 2001) and nutrient cycling (Strauss et al. 2012), 2. influencing hydrological properties of soil such as the water balance (Chamizo et al. 2016), and 3. The thermal energy balance of the ecosystem (Coradeau et al. 2016, Rutherford et al. 2017).

Plant and Soil↗
USGS2012

Predicting ecological flow regime at ungaged sites: A comparison of methods

Nineteen ecologically relevant streamflow characteristics were estimated using published rainfall–runoff and regional regression models for six sites with observed daily streamflow records in Kentucky. The regional regression model produced median estimates closer to the observed median for all but two characteristics. The variability of predictions from both models was generally less than the observed variability. The variability of the predictions from the rainfall–runoff model was greater than that from the regional regression model for all but three characteristics. Eight characteristics predicted by the rainfall–runoff model display positive or negative bias across all six sites; biases are not as pronounced for the regional regression model. Results suggest that a rainfall–runoff model calibrated on a single characteristic is less likely to perform well as a predictor of a range of other characteristics (flow regime) when compared with a regional regression model calibrated individually on multiple characteristics used to represent the flow regime. Poor model performance may misrepresent hydrologic conditions, potentially distorting the perceived risk of ecological degradation. Without prior selection of streamflow characteristics, targeted calibration, and error quantification, the widespread application of general hydrologic models to ecological flow studies is problematic. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Kentucky, Tennessee↗
USGS2017

Highest pluvial-lake shorelines and Pleistocene climate of the western Great Basin

Shoreline altitudes of several pluvial lakes in the western Great Basin of North America record successively smaller lakes from the early to the late Pleistocene. This decrease in lake size indicates a long-term drying trend in the regional climate that is not seen in global marine oxygen-isotope records. At +70 m above its late Pleistocene shoreline, Lake Lahontan in the early middle Pleistocene submerged some basins previously thought to have been isolated. Other basins known to contain records of older pluvial lakes that exceeded late Pleistocene levels include Columbus-Fish Lake (Lake Columbus-Rennie), Kobeh-Diamond (Lakes Jonathan and Diamond), Newark, Long (Lake Hubbs), and Clover. Very high stands of some of these lakes probably triggered overflows of previously internally drained basins, adding to the size of Lake Lahontan. Simple calculations based on differences in lake area suggest that the highest levels of these pluvial lakes required a regional increase in effective moisture by a factor of 1.2 to 3 relative to late Pleistocene pluvial amounts (assuming that effective moisture is directly proportional to the hydrologic index, or lake area/tributary basin area). These previously unknown lake levels reflect significant changes in climate, tectonics, and (or) drainage-basin configurations, and could have facilitated migration of aquatic species in the Great Basin.

Quaternary Research↗
USGS2003

Seasonal deuterium excess in a Tien Shan ice core: Influence of moisture transport and recycling in Central Asia

Stable water isotope (δ 18 O, δD) data from a high elevation (5100 masl) ice core recovered from the Tien Shan Mountains, Kyrgyzstan, display a seasonal cycle in deuterium excess (d = δD - 8*δ 18 O) related to changes in the regional hydrologic cycle during 1994-2000. While there is a strong correlation (r 2 = 0.98) between δ 18 O and δD in the ice core samples, the regression slope (6.9) and mean d value (23.0) are significantly different than the global meteoric water line values. The resulting time-series ice core d profile contains distinct winter maxima and summer minima, with a yearly d amplitude of ∼15-20‰. Local-scale processes that may affect d values preserved in the ice core are not consistent with the observed seasonal variability. Data from Central Asian monitoring sites in the Global Network of Isotopes in Precipitation (GNIP) have similar seasonal d changes. We suggest that regional-scale hydrological conditions, including seasonal changes in moisture source, transport , and recycling in the Caspian/Aral Sea region, are responsible for the observed spatial and temporal d variability.

Geophysical Research Letters↗
USGS2010

Some basic considerations in the design of hydrologic data networks

Two preeminent considerations of data network design are the random nature of the hydrologic phenomena and the uses that will be made of the data. Information distilled from the data is usually measured in a parametric statistical sense, although the data user is more concerned with the integrated measure of information - what impact does the lack of perfect hydrologic information have on the ensuing decisions? Two facets of the network, the efficiency of the data collection and the effectiveness of the resulting information, must be integrated to achieve a complete network design.

Water Resources Research↗
USGS2026

A review and synthesis of post-wildfire shifts in hydrologic processes and streamflow generation mechanisms

Critical water supply watersheds in the western United States (WUS) are impacted by wildfires, with potential negative effects on water quality and quantity. Scientific understanding is currently insufficient to deliver estimates of wildfire consequences for water quantity that are regionally accurate. Regional variability in the directionality and magnitude of post-wildfire shifts in streamflow generation fuels uncertainty in estimates of wildfire effects on water supply. In this work we provide a narrative review of wildfire effects on hydrologic processes and the resulting changes in streamflow generation mechanisms with a focus on the WUS, incorporating other global regions when pertinent. A conceptual model summary of wildfire effects on streamflow generation emphasizes: (1) precipitation seasonality, (2) synchrony of precipitation and potential evapotranspiration, (3) net shifts in interception, evaporation, and transpiration relative to total annual precipitation, (4) vegetation changes, including compensatory uptake and type conversion, (5) degree of overlap in rainfall rates and infiltration, (6) fire extent and severity, (7) burn scar positioning (e.g. in headwaters or proximal to watershed outlet), (8) scale-dependent groundwater leakage, (9) near-surface water storage reduction, and (10) soil to groundwater connectivity. Ongoing gaps and challenges include separating the influences of precipitation variability, water withdrawals, and post-fire land management; compound and overlapping disturbances; and lack of pre-fire data. Notable future opportunities include: harnessing ever-improving gridded and remotely sensed precipitation and fire-effects data; linking geophysical, isotopic tracer, and geochemical signatures to diagnose hydrologic changes; leveraging physically based and data-driven model advancements; and analyzing streamflow generation recovery trajectories across diverse watersheds.

western United States↗