Stable isotopes in atmospheric water vapor and applications to the hydrologic cycle
TL;DR: Improved measurement and modeling of water vapor isotopic composition opens the door to new advances in the understanding of the atmospheric water cycle, in processes ranging from the marine boundary layer, through deep convection and tropospheric mixing, and into the water cycle of the stratosphere.
Abstract: The measurement and simulation of water vapor isotopic composition has matured rapidly over the last decade, with long-term datasets and comprehensive modeling capabilities now available. Theories for water vapor isotopic composition have been developed by extending the theories that have been used for the isotopic composition of precipitation to include a more nuanced understanding of evaporation, large-scale mixing, deep convection, and kinetic fractionation. The technologies for in-situ and remote sensing measurements of water vapor isotopic composition have developed especially rapidly over the last decade, with discrete water vapor sampling methods, based on mass spectroscopy, giving way to laser spectroscopic methods and satellite- and ground-based infrared absorption techniques. The simulation of water vapor isotopic composition has evolved from General Circulation Model (GCM) methods for simulating precipitation isotopic composition to sophisticated isotope-enabled microphysics schemes using higher-order moments for water- and ice-size distributions. The incorporation of isotopes into GCMs has enabled more detailed diagnostics of the water cycle and has led to improvements in its simulation. The combination of improved measurement and modeling of water vapor isotopic composition opens the door to new advances in our understanding of the atmospheric water cycle, in processes ranging from the marine boundary layer, through deep convection and tropospheric mixing, and into the water cycle of the stratosphere. Finally, studies of the processes governing modern water vapor isotopic composition provide an improved framework for the interpretation of paleoclimate proxy records of the hydrological cycle.
Citations
More filters
TL;DR: This analysis provides compelling observational evidence that rainforest transpiration during the late dry season plays a central role in initiating the dry-to-wet season transition over the southern Amazon, and provides a mechanistic framework for understanding how deforestation extends the dry season and enhances regional vulnerability to drought.
Abstract: Although it is well established that transpiration contributes much of the water for rainfall over Amazonia, it remains unclear whether transpiration helps to drive or merely responds to the seasonal cycle of rainfall. Here, we use multiple independent satellite datasets to show that rainforest transpiration enables an increase of shallow convection that moistens and destabilizes the atmosphere during the initial stages of the dry-to-wet season transition. This shallow convection moisture pump (SCMP) preconditions the atmosphere at the regional scale for a rapid increase in rain-bearing deep convection, which in turn drives moisture convergence and wet season onset 2–3 mo before the arrival of the Intertropical Convergence Zone (ITCZ). Aerosols produced by late dry season biomass burning may alter the efficiency of the SCMP. Our results highlight the mechanisms by which interactions among land surface processes, atmospheric convection, and biomass burning may alter the timing of wet season onset and provide a mechanistic framework for understanding how deforestation extends the dry season and enhances regional vulnerability to drought.
184 citations
Cites background or methods from "Stable isotopes in atmospheric wate..."
...2D) also imply ABL growth and more frequent shallow cumulus....
[...]
...Changes in the vertical profile of relative humidity (RH) suggest that enhanced sensible heating deepens the daytime ABL, mixing dry free tropospheric air into the ABL and moist ABL air into the free troposphere (Fig....
[...]
...The models correspond to dry mixing, reversible moist adiabatic ascent, and Rayleigh distillation (33, 37)....
[...]
...We quantify conditional instability as the difference in θe between 850 hPa, slightly above the ABL top, and 500 hPa, in the middle troposphere (Fig....
[...]
...In situ observations indicate that maximum ET leads the late dry season increase in rainfall (26–28); however, it has been unclear whether modest increases in ET can contribute sufficient moisture above the ABL at regional scales....
[...]
Journal Article•
TL;DR: This article identified several errors in the calculations that were performed to create Fig. 3 of Del Genio et al. (2012), which affect the composite evolution of precipitation and column water vapor versus lag relative to the Madden-Julian oscillation (MJO) peak presented in that figure.
Abstract: We have identified several errors in the calculations that were performed to create Fig. 3 of Del Genio et al. (2012). These errors affect the composite evolution of precipitation and column water vapor versus lag relative to the Madden-Julian oscillation (MJO) peak presented in that figure. The precipitation and column water vapor data for the April and November 2009 MJO events were composited incorrectly because the date of the MJO peak at a given longitude was assigned to the incorrect longitude band. In addition, the precipitation data for all MJO events were first accumulated daily and the daily accumulations averaged at each lag to create the composite, rather than the averaging of instantaneous values that was used for other composite figures in the paper. One poorly sampled day in the west Pacific therefore biases the composite precipitation in that region at several lags after the MJO peak. Finally, a 4-day running mean was mistakenly applied to the precipitation and column water vapor data rather than the intended 5-day running mean. The results of the corrections are that an anomalous west Pacific precipitation maximum510 days after the MJO peak is removed and the maximum in west Pacific precipitation one pentad before the MJO peak is now more evident; there is now a clear maximum in precipitation for the entire warm pool one pentad before the MJO peak; west Pacific column water vapor now varies more strongly as a function of lag relative to the peak; and precipitation, and to a lesser extent column water vapor, in general vary more smoothly with time. The corrections do not affect any other parts of the paper nor do they change the scientific conclusions we reached. The 4-day running mean error also affects Figs. 1 and 2 therein, with almost imperceptible impacts that do not affect any results or necessitate major changes to the text.
156 citations
TL;DR: The MOSAiC program as mentioned in this paper was organized into four subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets, using a variety of approaches, and across multiple scales.
Abstract: With the Arctic rapidly changing, the needs to observe, understand, and model the changes are essential. To support these needs, an annual cycle of observations of atmospheric properties, processes, and interactions were made while drifting with the sea ice across the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. An international team designed and implemented the comprehensive program to document and characterize all aspects of the Arctic atmospheric system in unprecedented detail, using a variety of approaches, and across multiple scales. These measurements were coordinated with other observational teams to explore cross-cutting and coupled interactions with the Arctic Ocean, sea ice, and ecosystem through a variety of physical and biogeochemical processes. This overview outlines the breadth and complexity of the atmospheric research program, which was organized into 4 subgroups: atmospheric state, clouds and precipitation, gases and aerosols, and energy budgets. Atmospheric variability over the annual cycle revealed important influences from a persistent large-scale winter circulation pattern, leading to some storms with pressure and winds that were outside the interquartile range of past conditions suggested by long-term reanalysis. Similarly, the MOSAiC location was warmer and wetter in summer than the reanalysis climatology, in part due to its close proximity to the sea ice edge. The comprehensiveness of the observational program for characterizing and analyzing atmospheric phenomena is demonstrated via a winter case study examining air mass transitions and a summer case study examining vertical atmospheric evolution. Overall, the MOSAiC atmospheric program successfully met its objectives and was the most comprehensive atmospheric measurement program to date conducted over the Arctic sea ice. The obtained data will support a broad range of coupled-system scientific research and provide an important foundation for advancing multiscale modeling capabilities in the Arctic.
111 citations
TL;DR: The water isotope-enabled version of the Community Earth System Model version 1 (iCESM1) is presented in this article to simulate global variations in water isotopic ratios in the atmosphere, land, ocean, and sea ice.
Abstract: Because of the pervasive role of water in the Earth system, the relative abundances of stable isotopologues of water are valuable for understanding atmospheric, oceanic, and biospheric processes, and for interpreting paleoclimate proxy reconstructions. Isotopologues are transported by both largescale and turbulent flows, and the ratio of heavy to light isotopologues changes due to fractionation that can accompany condensation and evaporation processes. Correctly predicting the isotopic distributions requires resolving the relationships between largescale ocean and atmospheric circulation and smallerscale hydrological processes, which can be accomplished within a coupled climate modeling framework. Here we present the water isotopeenabled version of the Community Earth System Model version 1 (iCESM1), which simulates global variations in water isotopic ratios in the atmosphere, land, ocean, and sea ice. In a transient Last Millennium simulation covering the 850-2005 period, iCESM1 correctly captures the latetwentiethcentury structure of δ(exp 18)O and δD over the global oceans, with more limited accuracy over land. The relationship between salinity and seawater δ(exp 18)O is also well represented over the observational period, including interbasin variations. We illustrate the utility of coupled, isotopeenabled simulations using both Last Millennium simulations and freshwater hosing experiments with iCESM1. Closing the isotopic mass balance between all components of the coupled model provides new confidence in the underlying depiction of the water cycle in CESM, while also highlighting areas where the underlying hydrologic balance can be improved. The iCESM1 is poised to be a vital community resource for ongoing model development with both modern and paleoclimate applications.
105 citations
Cites background from "Stable isotopes in atmospheric wate..."
...…condensation, and isotopic exchange between raindrops and the surrounding vapor; interaction between large‐scale and turbulent‐scale transport; and variation in moisture source regions (Craig, 1961; Craig & Gordon, 1965; Dansgaard, 1964; Epstein et al., 1965; Gat, 2000; Galewsky et al., 2016)....
[...]
...This is particularly valuable given the recent advent of global data sets from satellite instruments and high‐frequency in situ spectrometer measurements (for a recent survey of isotope ratio data sets, see Galewsky et al. (2016))....
[...]
...As such, the observational community is beginning to leverage these capacities of water isotopes (Berkelhammer et al., 2012; Galewsky et al., 2016; Kuang et al., 2003; Noone, 2012; Tremoy et al., 2014)....
[...]
TL;DR: In this article, a review summarizes the state of knowledge of how different hydro-meteorological processes affect the isotopic composition of snow, and, through selected examples, discusses how stable water isotopes can provide a better understanding of snow hydrological processes.
Abstract: Snowfall may have different stable isotopic compositions compared to rainfall, allowing its contribution to potentially be tracked through the hydrological cycle. This review summarizes the state of knowledge of how different hydro-meteorological processes affect the isotopic composition of snow, and, through selected examples, discusses how stable water isotopes can provide a better understanding of snow hydrological processes. A detailed account is given of how the variability in isotopic composition of snow changes from precipitation to final melting. The effect of different snow ablation processes (sublimation, melting, and redistribution by wind or avalanches) on the isotope ratios of the underlying snowpack are also examined. Insights into the role of canopy in snow interception processes, and how the isotopic composition in canopy underlying snowpacks can elucidate the exchanges therein are discussed, as well as case studies demonstrating the usefulness of stable water isotopes to estimate seasonality in the groundwater recharge. Rain-on-snow floods illustrate how isotopes can be useful to estimate the role of preferential flow during heavy spring rains. All these examples point to the complexity of snow hydrologic processes and demonstrate that an isotopic approach is useful to quantify snow contributions throughout the water cycle, especially in high elevation and high latitude catchments, where such processes are most pronounced. This synthesis concludes by tracing a snow particle along its entire hydrologic life cycle, highlights the major practical challenges remaining in snow hydrology and discusses future research directions.
87 citations
Cites background from "Stable isotopes in atmospheric wate..."
...In the last decade, (17)O has been suggested as an additional tracer to better constrain the hydrologic cycle (Berman, Levin, Landais, Li, & Owano, 2013; Birkel & Soulsby, 2015; Galewsky et al., 2016)....
[...]
...The basic concepts of how H and O isotopes are used in hydrology are summarized following Galewsky et al. (2016)....
[...]
...The intercept of the GMWL is referred to as d-excess (deuterium-excess factor) and is useful in distinguishing equilibrium and nonequilibrium processes (see hereafter) (Dansgaard, 1964; Galewsky et al., 2016)....
[...]
...As moist air masses uplift (adiabatically) along a mountain range, condensation occurs at lower temperatures, which is also known as the lapse rate (Friedman, Smith, Gleason, Warden, & Harris, 1992; Galewsky et al., 2016; Winograd et al., 1998)....
[...]
...In the last decade, 17O has been suggested as an additional tracer to better constrain the hydrologic cycle (Berman, Levin, Landais, Li, & Owano, 2013; Birkel & Soulsby, 2015; Galewsky et al., 2016)....
[...]
References
More filters
TL;DR: In this paper, the isotopic fractionation of water in simple condensation-evaporation processes is considered quantitatively on the basis of the fractionation factors given in section 1.2.
Abstract: In chapter 2 the isotopic fractionation of water in some simple condensation-evaporation processes are considered quantitatively on the basis of the fractionation factors given in section 1.2. The condensation temperature is an important parameter, which has got some glaciological applications. The temperature effect (the δ's decreasing with temperature) together with varying evaporation and exchange appear in the “amount effect” as high δ's in sparse rain. The relative deuterium-oxygen-18 fractionation is not quite simple. If the relative deviations from the standard water (S.M.O.W.) are called δ D and δ 18 , the best linear approximation is δ D = 8 δ 18 . Chapter 3 gives some qualitative considerations on non-equilibrium (fast) processes. Kinetic effects have heavy bearings upon the effective fractionation factors. Such effects have only been demonstrated clearly in evaporation processes, but may also influence condensation processes. The quantity d = δ D −8 δ 18 is used as an index for non-equilibrium conditions. The stable isotope data from the world wide I.A.E.A.-W.M.O. precipitation survey are discussed in chapter 4. The unweighted mean annual composition of rain at tropical island stations fits the line δ D = 4.6 δ 18 indicating a first stage equilibrium condensation from vapour evaporated in a non-equilibrium process. Regional characteristics appear in the weighted means. The Northern hemisphere continental stations, except African and Near East, fit the line δ D = 8.0 δ 18 + 10 as far as the weighted means are concerned (δ D = 8.1 δ 18 + 11 for the unweighted) corresponding to an equilibrium Rayleigh condensation from vapour, evaporated in a non-equilibrium process from S.M.O.W. The departure from equilibrium vapour seems even higher in the rest of the investigated part of the world. At most stations the δ D and varies linearily with δ 18 with a slope close to 8, only at two stations higher than 8, at several lower than 8 (mainly connected with relatively dry climates). Considerable variations in the isotopic composition of monthly precipitation occur at most stations. At low latitudes the amount effect accounts for the variations, whereas seasonal variation at high latitudes is ascribed to the temperature effect. Tokyo is an example of a mid latitude station influenced by both effects. Some possible hydrological applications are outlined in chapter 5. DOI: 10.1111/j.2153-3490.1964.tb00181.x
7,081 citations
TL;DR: The relationship between deuterium and oxygen-18 concentrations in natural meteoric waters from many parts of the world has been determined with a mass spectrometer and shows a linear correlation over the entire range for waters which have not undergone excessive evaporation.
Abstract: The relationship between deuterium and oxygen-18 concentrations in natural meteoric waters from many parts of the world has been determined with a mass spectrometer. The isotopic enrichments, relative to ocean water, display a linear correlation over the entire range for waters which have not undergone excessive evaporation.
6,721 citations
"Stable isotopes in atmospheric wate..." refers background in this paper
...The 𝛿D and 𝛿18O in meteoric waters vary nearly linearly and can be fit to the equation 𝛿D = 8 × 𝛿18O + d-excess [Craig, 1961] where d-excess is the deuterium excess parameter [Dansgaard, 1964]....
[...]
...With the definition of the Global Meteoric Water line [Craig, 1961; Dansgaard, 1964], the d-excess of both present-day and archived water samples (ice core and ground water) can be calculated....
[...]
...Globally, the average d-excess in meteoric water is 10‰ [Craig, 1961]....
[...]
Book•
17 Jul 2000
TL;DR: This book treats the inverse problem of remote sounding comprehensively, and discusses a wide range of retrieval methods for extracting atmospheric parameters of interest from the quantities such as thermal emission that can be measured remotely.
Abstract: Remote sounding of the atmosphere has proved to be a fruitful method of obtaining global information about the atmospheres of the earth and planets. This book treats the inverse problem of remote sounding comprehensively, and discusses a wide range of retrieval methods for extracting atmospheric parameters of interest from the quantities such as thermal emission that can be measured remotely. Inverse theory is treated in depth from an estimation-theory point of view, but practical questions are also emphasized, for example designing observing systems to obtain the maximum quantity of information, efficient numerical implementation of algorithms for processing of large quantities of data, error analysis and approaches to the validation of the resulting retrievals, The book is targeted at both graduate students and working scientists.
4,052 citations
"Stable isotopes in atmospheric wate..." refers methods in this paper
...…may be related to the true distribution of that quantity and corresponding uncertainties associated with the measurement in the following manner [Rodgers, 2000]: x̂ = xa + A(x − xa) + Gn + G ∑ i Ki𝛿i (8) where x̂, xa, and x are the retrieved (or estimated), a priori, and the “true” state…...
[...]
...When comparing remote sensing data with in situ data or with model data, the retrieval’s regularization should be taken into account [Rodgers, 2000]....
[...]
...The parameters xa,A, and G explicitly contain the regularization used to constrain the ill-posed nature of the remote sensing retrieval problem [e.g., Rodgers, 2000; Bowman et al., 2006] if an optimal estimation approach is used to guide the retrieval....
[...]
TL;DR: A number of marine water and fresh water samples were examined for the relative O18O16 ratio, and the variation of this ratio was determined to a precision of ± 1% as mentioned in this paper.
3,113 citations
TL;DR: In this paper, a very pronounced maximum was noted in the co-spectrum of the 850- and 150-mb zonal wind components in the frequency range 0.0245-0.0190 day−1 (41-53 days period).
Abstract: Nearly ten years of daily rawinsonde data for Canton Island (3S, 172W) have been subjected to spectrum and cross-spectrum analysis. In the course of this analysis a very pronounced maximum was noted in the co-spectrum of the 850- and 150-mb zonal wind components in the frequency range 0.0245–0.0190 day−1 (41–53 days period). Application of a posteriori sampling theory resulted in a significance level of ∼6% (0.1% prior confidence level). This type of significance test is appropriate because no prior evidence or reason existed for expecting such a spectral feature. Subsequent analysis revealed the following structure of the oscillation. Peaks in the variance spectra of the zonal wind are strong in the low troposphere, are weak or non-existent in the 700–400 mb layer, and are strong again in the upper troposphere. No evidence of this feature could be found above 80 mb, or in any of the spectra of the meridional component. The spectrum of station pressure possesses a peak in this frequency range and...
2,995 citations
"Stable isotopes in atmospheric wate..." refers background in this paper
...The Madden-Julian Oscillation (MJO) is the dominant mode of intraseasonal variability in the tropics [Madden and Julian, 1971, 1972; Zhang, 2005]....
[...]