This report details ocean water salinity and stable isotope measurements (deuterium (D) and 18O) in water collected from April 17 2018 to April 21 2018 in the coastal waters of Oregon, USA. Measurements were made from surface, ship flow-through, and CTD rosette bottle samples collected as part of a student-led...
Climate model simulations and paleoclimate proxies are two tools that enable an understanding of the climate history of the Earth. When utilized together, they form a powerful paradigm for understanding past changes. Proxies are the only physical link to the past conditions on Earth, and models “fill in the gaps”...
A synthesis of over 2000 paleoclimate proxy records is performed via a data assimilation framework that expands upon previous efforts by implementing a suite of physically-based proxy system models, and which provides the first example of an observationally independent, multi-seasonal (DJFM, JJAS) paleoclimate reanalysis. This methodology is contrasted against previous...
The National Ecological Observatory Network (NEON) provides open access data products including sub-daily precipitation amounts and biweekly stable water isotope concentrations at sites across the United States. Stable water isotope (ẟ2H, ẟ18O) concentrations are often used in hydrometeorological studies and models, however the relatively infrequent biweekly sampling intervals of NEON...
Uncertainties in general circulation model (GCM) representations of marine boundary layer (MBL) shallow cloud cover contribute substantially to the spread in model predictions of future climate. Further uncertainties in GCM output arise from an incomplete understanding of cloud-aerosol interactions. For example, the Fifth Assessment Report from the Intergovernmental Panel on...
Noise is an environmental issue uniquely harmful to public welfare but essential to a well-functioning modern economy. Given the prevalence of noise especially in urban soundscapes, noise pollution has been recognized as a negative externality and an environmental stressor and thus has become an issue in public policy. Yet, as...
Deuterium to hydrogen (D/H) ratios in Earth’s hydrologic cycle have long served as important tracers of climate processes, yet the global HDO budget remains poorly constrained because of uncertainties in the isotopic compositions of continental evapotranspiration and runoff. Here bias-corrected satellite retrievals of HDO and H₂O concentrations from the Tropospheric...
Transpiration (T), or the evaporation of water through plant stomata, plays a critical role in climate and biophysical processes at the earth’s surface. While T makes up a majority of the terrestrial evapotranspiration (ET) flux on a global scale, the partitioning of ET is variable and remains elusive. Because photosynthetic...
With water vapor and clouds expected to effect significant feedbacks on climate, moisture transport through convective processes has important implications for future temperature change. The precipitation efficiency—the ratio of the rates at which precipitation and condensation form (e = P/C)—is useful for characterizing how much boundary layer moisture recycles through precipitation versus...
An increase in anthropogenic activities since the industrial revolution, primarily due to burning of fossil fuels and changes in land cover, has resulted in a steady increase in the global mean atmospheric CO2 concentrations. While there is unequivocal scientific evidence on global warming and its multidimensional impacts on natural and...
Climate change impacts everyone’s food and water security. Increasing global temperatures accelerate the hydrologic cycle and consequently impact the water resources for billions of people worldwide. Countless models have been developed to represent various components of the hydrologic cycle at various spatial and temporal scales. These are often validated against...
Continental precipitation not routed to the oceans as runoff returns to the atmosphere
as evapotranspiration. Partitioning this evapotranspiration flux into interception, transpiration,
soil evaporation, and surface water evaporation is difficult using traditional hydrological
methods yet critical for understanding the water cycle and linked ecological processes. We
combined two large-scale flux-partitioning...
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water fluxes
Good, S. P., Noone, D., & Bowen, G. (2015). Hydrologic connectivity constrains
Continental precipitation not routed to the oceans as runoff returns to the atmosphere
as evapotranspiration. Partitioning this evapotranspiration flux into interception, transpiration,
soil evaporation, and surface water evaporation is difficult using traditional hydrological
methods yet critical for understanding the water cycle and linked ecological processes. We
combined two large-scale flux-partitioning...
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Fluxes
Stephen P. Good, David Noone, Gabriel Bowen
correspondence to: stephen.good@oregonstate.edu
In 2011, the Institute for Natural Resources – Portland (INR) entered into an agreement with the Natural Resources Conservation Service through the Cooperative Ecosystem Study Unit to assist in evaluation of a targeted watershed restoration area in central Oregon. The primary objective of the agreement was to use remote sensing...
A new matrix operator framework is developed to analyze results from climate modeling studies that employ numerical water tracers (WTs), which track the movement of water in the aerial hydrological cycle from evaporation to precipitation. Model WT output is related to the fundamental equation of hydrology, and the moisture flux...
Pine Creek Conservation Area (PCCA), just northeast of the John Day River in Wheeler County, Oregon, was acquired in 1999-2001 by the Confederate Tribes of Warm Springs with support from the Bonneville Power Administration (BPA), to mitigate for wildlife losses created by the large, hydropower Columbia River Dams, particularly the...
With the recent advent of commercial laser absorption spectrometers, field studies measuring stable isotope ratios of hydrogen and oxygen in water vapor have proliferated. These pioneering analyses have provided invaluable feedback about best strategies for optimizing instrumental accuracy, yet questions still remain about instrument performance and calibration approaches for multi-year...
With the recent advent of commercial laser absorption spectrometers, field studies measuring stable isotope ratios of hydrogen and oxygen in water vapor have proliferated. These pioneering analyses have provided invaluable feedback about best strategies for optimizing instrumental accuracy, yet questions still remain about instrument performance and calibration approaches for multi-year...
This research examines the effect of recent landownership changes and new management stewardship
mechanisms (e.g., forest certification and working forest conservation easements) on disturbance rates in Maine
forests. We quantify forest disturbance rates between 2000 and 2007 and forest cover type composition in 2007,
as detected by Landsat Thematic Mapper...
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% (Noone 2009). The recent
changes in Maine’s forest landscape and ownership patterns require frequent
This research examines the effect of recent landownership changes and new management stewardship
mechanisms (e.g., forest certification and working forest conservation easements) on disturbance rates in Maine
forests. We quantify forest disturbance rates between 2000 and 2007 and forest cover type composition in 2007,
as detected by Landsat Thematic Mapper...
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d
o
w
n
e
r
c
h
a
n
g
e
g
ro
u
p
s
Landowner groups
Total hectares
harvestable
This research examines the effect of recent landownership changes and new management stewardship mechanisms (e.g., forest certification and working forest conservation easements) on disturbance rates in Maine forests. We quantify forest disturbance rates between 2000 and 2007 and forest cover type composition in 2007, as detected by Landsat Thematic Mapper...
Understanding the processes that control the terrestrial exchange of carbon is critical for
assessing atmospheric CO₂ budgets. Carbonyl sulfide (COS) is taken up by vegetation during
photosynthesis following a pathway that mirrors CO₂ but has a small or nonexistent emission component,
providing a possible tracer for gross primary production. Field...
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D. Asaf
Weizmann Inst.
C. Still
Oregon State U.
S. Montzka
NOAA-ESRL
D. Noone
U
Understanding the processes that control the terrestrial exchange of carbon is critical for
assessing atmospheric CO₂ budgets. Carbonyl sulfide (COS) is taken up by vegetation during
photosynthesis following a pathway that mirrors CO₂ but has a small or nonexistent emission component,
providing a possible tracer for gross primary production. Field...
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measurements of
carbonyl sulfide and carbon dioxide
Berkelhammer, M., D. Asaf, C. Still, S. Montzka, D. Noone
Understanding the processes that control the terrestrial exchange of carbon is critical for
assessing atmospheric CO₂ budgets. Carbonyl sulfide (COS) is taken up by vegetation during
photosynthesis following a pathway that mirrors CO₂ but has a small or nonexistent emission component,
providing a possible tracer for gross primary production. Field...
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d
sp
ee
d
(m
/s
)
-60
-40
-20
0
20
40
CO
S
A
no
m
al
y
(p
m
ol
m
ol
-1
Understanding the processes that control the terrestrial exchange of carbon is critical for
assessing atmospheric CO₂ budgets. Carbonyl sulfide (COS) is taken up by vegetation during
photosynthesis following a pathway that mirrors CO₂ but has a small or nonexistent emission component,
providing a possible tracer for gross primary production. Field...
The delta O-18 signal preserved in paleoarchives is widely used to reconstruct past climate conditions. In many speleothems, this signal is classically interpreted via the amount effect. However, recent work has shown that precipitation delta O-18 (delta O-18(p)) is greatly influenced by convective processes distinct from precipitation amount, and new...
This study investigates the response of the global mean and spatial variations of the δ¹⁸O value of atmospheric CO₂ (δCₐ) to changes in soil CO₂ hydration rates, relative humidity, the δ¹⁸O value of precipitation and water vapor, visible radiation, temperature, and ecosystem flux partitioning. A three-dimensional global transport model was...
Deuterium to hydrogen (D/H) ratios in Earth’s hydrologic cycle have long served as important
tracers of climate processes, yet the global HDO budget remains poorly constrained because of uncertainties
in the isotopic compositions of continental evapotranspiration and runoff. Here bias-corrected satellite retrievals of
HDO and H₂O concentrations from the Tropospheric...
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D/H isotope ratios in the global hydrologic cycle
Good, S. P., Noone, D., Kurita, N., Benetti, M
Deuterium to hydrogen (D/H) ratios in Earth’s hydrologic cycle have long served as important
tracers of climate processes, yet the global HDO budget remains poorly constrained because of uncertainties
in the isotopic compositions of continental evapotranspiration and runoff. Here bias-corrected satellite retrievals of
HDO and H₂O concentrations from the Tropospheric...
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, Aquat. Geochemistry, 15(4), 497–527, 289
doi:10.1007/s10498-009-9063-6. 290
Noone, D. et al. (2013
Deuterium to hydrogen (D/H) ratios in Earth’s hydrologic cycle have long served as important
tracers of climate processes, yet the global HDO budget remains poorly constrained because of uncertainties
in the isotopic compositions of continental evapotranspiration and runoff. Here bias-corrected satellite retrievals of
HDO and H₂O concentrations from the Tropospheric...
Deuterium to hydrogen (D/H) ratios in Earth’s hydrologic cycle have long served as important
tracers of climate processes, yet the global HDO budget remains poorly constrained because of uncertainties
in the isotopic compositions of continental evapotranspiration and runoff. Here bias-corrected satellite retrievals of
HDO and H₂O concentrations from the Tropospheric...
Understanding controls on the stable isotopic composition of precipitation and vapor in the West Pacific Warm Pool is vital for accurate representation of convective processes in models and correct interpretation of isotope-based paleoclimate proxies, yet a lack of direct observational evidence precludes the utility of these isotopic tracers. Results from...
Understanding controls on the stable isotopic composition of precipitation and vapor in the West Pacific Warm Pool is vital for accurate representation of convective processes in models and correct interpretation of isotope-based paleoclimate proxies, yet a lack of direct observational evidence precludes the utility of these isotopic tracers. Results from...
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Citation:
Conroy, J. L., D. Noone, K. M. Cobb,
J. W. Moerman, and B. L. Konecky (2016),
Paired stable
Understanding controls on the stable isotopic composition of precipitation and vapor in the West Pacific Warm Pool is vital for accurate representation of convective processes in models and correct interpretation of isotope-based paleoclimate proxies, yet a lack of direct observational evidence precludes the utility of these isotopic tracers. Results from...
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δD
(‰
V
S
M
O
W
)
H2O (ppmv)
H2O (ppmv)
3
Date Time
δ18O
( ‰ VSMOW) ±
δD
Understanding controls on the stable isotopic composition of precipitation and vapor in the West Pacific Warm Pool is vital for accurate representation of convective processes in models and correct interpretation of isotope-based paleoclimate proxies, yet a lack of direct observational evidence precludes the utility of these isotopic tracers. Results from...
Rapid Arctic warming is associated with important water cycle changes: sea ice loss, increasing atmospheric humidity, permafrost thaw, and water-induced ecosystem changes. Understanding these complex modern processes is critical to interpreting past hydrologic changes preserved in paleoclimate records and predicting future Arctic changes. Cyclones are a prevalent Arctic feature and...
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recorded in Greenland ice
Klein, E. S., Cherry, J. E., Young, J., Noone, D., Leffler, A. J., & Welker, J
Rapid Arctic warming is associated with important water cycle changes: sea ice loss, increasing atmospheric humidity, permafrost thaw, and water-induced ecosystem changes. Understanding these complex modern processes is critical to interpreting past hydrologic changes preserved in paleoclimate records and predicting future Arctic changes. Cyclones are a prevalent Arctic feature and...
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ice retreat recorded in Greenland ice
Eric S. Klein
1*
, J. E. Cherry
2
, J. Young
2
, D. Noone
Rapid Arctic warming is associated with important water cycle changes: sea ice loss, increasing atmospheric humidity, permafrost thaw, and water-induced ecosystem changes. Understanding these complex modern processes is critical to interpreting past hydrologic changes preserved in paleoclimate records and predicting future Arctic changes. Cyclones are a prevalent Arctic feature and...
Reconstructions of the El Niño–Southern Oscillation (ENSO) are often created using the oxygen isotopic ratio in tropical coral skeletons (δ¹⁸O). However, coral δ¹⁸O can be difficult to interpret quantitatively, as it reflects changes in both temperature and the δ¹⁸O value of seawater. Small-scale (10–100 km) processes affecting local temperature and...
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, Merrifield, M.1, Cobb, K.3, Nusbaumer, J.4 & Noone, D.5
1Department of Oceanography, University of Hawaii
Reconstructions of the El Niño–Southern Oscillation (ENSO) are often created using the oxygen isotopic ratio in tropical coral skeletons (δ¹⁸O). However, coral δ¹⁸O can be difficult to interpret quantitatively, as it reflects changes in both temperature and the δ¹⁸O value of seawater. Small-scale (10–100 km) processes affecting local temperature and...
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D. Noone (2015),
Characterizing seawater oxygen
isotopic variability in a regional
ocean modeling
Reconstructions of the El Niño–Southern Oscillation (ENSO) are often created using the oxygen isotopic ratio in tropical coral skeletons (δ¹⁸O). However, coral δ¹⁸O can be difficult to interpret quantitatively, as it reflects changes in both temperature and the δ¹⁸O value of seawater. Small-scale (10–100 km) processes affecting local temperature and...
Prior to November 2010, when The Intertwine Alliance launched the Regional Conservation Strategy (RCS) and Biodiversity Guide (RBG) efforts for the Portland-Vancouver metropolitan region, conservation priorities in the metropolitan region were identified at a broad regional scale that generally excluded urban areas (e.g., state conservation strategies and Willamette Synthesis); were...
The movement of moisture into, out-of, and within forest ecosystems is modulated
by feedbacks that stem from processes which couple plants, soil, and the atmosphere.
While an understanding of these processes has been gleaned from Eddy Covariance
techniques, the reliability of the method suffers at night because of weak turbulence....
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The nocturnal water cycle in an open-canopy forest
Berkelhammer, M., J. Hu, A. Bailey, D. C. Noone, C
The movement of moisture into, out-of, and within forest ecosystems is modulated
by feedbacks that stem from processes which couple plants, soil, and the atmosphere.
While an understanding of these processes has been gleaned from Eddy Covariance
techniques, the reliability of the method suffers at night because of weak turbulence....
The movement of moisture into, out-of, and within forest ecosystems is modulated
by feedbacks that stem from processes which couple plants, soil, and the atmosphere.
While an understanding of these processes has been gleaned from Eddy Covariance
techniques, the reliability of the method suffers at night because of weak turbulence....
The Atlantic meridional overturning circulation (AMOC) is a key component of the global climate system. Recent studies suggested a twentieth-century weakening of the AMOC of unprecedented amplitude (similar to 15%) over the last millennium. Here we present a record of O-18 in benthic foraminifera from sediment cores retrieved from the...
General circulation models (GCMs) predict that the global hydrological cycle will change in response to anthropogenic warming. However, these predictions remain uncertain, in particular, for precipitation (Intergovernmental Panel on Climate Change, 2013, https://doi .org/10.1017/CB09781107415324.004). Held and Soden (2006, https://doi.org/10.1175/JCLI3990.1) suggest that as lower tropospheric water vapor concentration increases in a...
The isotopic composition of water vapour provides integrated perspectives on the hydrological histories of air masses and has been widely used for tracing physical processes in hydrological and climatic studies. Over the last two decades, the infrared laser spectroscopy technique has been used to measure the isotopic composition of water...
Mountainous headwater streams make up ~80 % of stream length globally and are strongly connected with catchment hillslopes and riparian areas, which can influence water quantity, quality, and availability for downstream uses. Accordingly, effective management of headwater streams and riparian zones to maintain desired ecosystem services downstream is critical, particularly...
Cloud reflectivity is a function of cloud liquid water content and droplet number concentration. Since cloud droplets form around pre-existing aerosol particles, cloud droplet number concentration depends on the availability of particles that can serve as cloud condensation nuclei. Given constant liquid water amount, increased availability of cloud condensation nuclei...
Small molecule drugs have been instrumental in our fight against diseases, beginning when some of the earliest ancient cultures used plant remedies to treat illnesses. More recently, the skill of isolating and characterizing the active ingredients within bioactive plants and microbial extracts has led to the isolation and design of...
Streams across the western United States are impaired from human alterations that have reduced freshwater habitat by simplifying channel complexity and disconnecting floodplains (Knox et al., 2022; Waples et al., 2008; Wohl, 2014). Climate change is likely to continue exacerbating these risks by warming summer surface stream temperatures (Crozier et...
Identifying habitat and spatial requirements of wildlife species across multiple spatial scales is a challenging, yet crucial component of wildlife management. Habitat use of bats is particularly difficult to study, and managing habitat to conserve bats is especially challenging because bats are highly vagile organisms that exploit several different types...
One-kilometer Advanced Very High Resolution Radiometer (AVHRR) observations of the effects of ships on
low-level clouds off the west coast of the United States are used to derive limits for the degree to which clouds
might be altered by increases in anthropogenic aerosols. As ships pass beneath low-level clouds, particles...
Using the counterflow virtual impactor, a new instrument for sampling cloud droplets, measurable levels of light-absorbing material were found to exist inside droplets in stratocumulus clouds off the coast of southern California. Eighty percent of the samples of droplet residue material had light absorption coefficients ranging from 6 to 20...
The southeast Pacific Ocean is covered by the world's largest stratocumulus cloud layer, which has a strong impact on ocean temperatures and climate in the region. The effect of anthropogenic sources of aerosol particles on the stratocumulus deck was investigated during the VOCALS field experiment. Aerosol measurements below and above...
Knowledge of cloud and precipitation formation processes remains
incomplete, yet global precipitation is predominantly produced by
clouds containing the ice phase. Ice first forms in clouds warmer
than −36 °C on particles termed ice nuclei. We combine observations
from field studies over a 14-year period, from a variety of
locations...
Cystic fibrosis is an inherited genetic disease caused by a single gene mutation in the CFTR protein. Affecting 70,000 people worldwide, this disease is debilitating to patients, resulting in persistent lung infections and decreased quality of life. Due to the various mutation types, there is not currently a single drug...
Direct interception of windblown cloud water by forests has been dubbed “occult deposition” because it represents a hydrological input that is hidden from rain gauges. Eddy correlation studies of this phenomenon have estimated cloud water fluxes to vegetation yet have lacked estimates of error bounds. This paper presents an evaluation...
Simulations of past climates require altered
boundary conditions to account for known shifts in the Earth
system. For the Last Glacial Maximum (LGM) and subsequent
deglaciation, the existence of large Northern Hemisphere
ice sheets caused profound changes in surface topography
and albedo. While ice-sheet extent is fairly well
known, numerous...
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Ullman, D. J., LeGrande, A. N., Carlson, A. E., Anslow, F. S., and Licciardi, J. M.:
Assessing the
The Antarctic contribution to sea level is a balance between ice loss along the margin and accumulation in the interior. Accumulation records for the past few decades are noisy and show inconsistent relationships with temperature. We investigate the relationship between accumulation and temperature for the past 31 ka using high-resolution records...
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, 475–494.
Noone, D., and I. Simmonds (2004), Sea ice control of water isotope transport to Antarctica
Certain bioactive food components, including indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM) from cruciferous vegetables, have been shown to target cellular pathways regulating carcinogenesis. Previously, our laboratory showed that dietary I3C is an effective transplacental chemopreventive agent in a dibenzo[def,p]chrysene (DBC)-dependent model of murine T-cell lymphoblastic lymphoma. The primary objective of the...
Data from nine stratocumulus clouds in the northeastern Pacific Ocean were analyzed
to determine the effect of aerosol particles on cloud microphysical and radiative properties.
Seven nighttime and two daytime cases were included. The number concentration of
below-cloud aerosol particles (> 0.10 μm diameter) was highly correlated with cloud
droplet...
In situ airborne sampling of refractory black carbon (rBC) particles and Ice Nuclei (IN) was conducted in and near an extratropical cyclonic storm in the western Pacific Ocean during the Pacific Dust Experiment, PACDEX, in the spring of 2007. Airmass origins were from Eastern Asia. Clouds associated primarily with the...
The influence of anthropogenic aerosols, in the form of ship exhaust effluent, on the microphysics and radiative properties of marine stratocumulus is studied using data gathered from the U.K. Met. Office C-130 and the University of Washington C-131A aircraft during the Monterey Area Ship Track (MAST) experiment in 1994. During...
The initiation of ice in an isolated orographic wave cloud was compared with expectations based on ice nucleating aerosol concentrations and with predictions from new ice nucleation parameterizations applied in a cloud parcel model. Measurements of ice crystal number concentrations were found to be in good agreement both with measured...
Formation of cirrus clouds depends on the availability of ice nuclei to begin condensation of atmospheric water vapor. Although it is known that only a small fraction of atmospheric aerosols are efficient ice nuclei, the critical ingredients that make those aerosols so effective have not been established. We have determined...
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. Targino, R. Krejci, K. J. Noone, P. Glantz,
Atmos. Chem. Phys. 6, 1977 (2006).
23. D. J. Cziczo et al
Formation of cirrus clouds depends on the availability of ice nuclei to begin condensation of atmospheric water vapor. Although it is known that only a small fraction of atmospheric aerosols are efficient ice nuclei, the critical ingredients that make those aerosols so effective have not been established. We have determined...
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the Dominant Sources and Mechanisms of Cirrus Cloud
Formation
Daniel J. Cziczo,* Karl D. Froyd
A continuous flow diffusion chamber (CFDC) was used to measure ice formation by
cloud particle residuals during the Cirrus Regional Study of Tropical Anvils and Cirrus
Layers-Florida Area Cirrus Experiment. These measurements were directed toward
determining the relative contributions of homogeneous nucleation, heterogeneous
nucleation, and secondary ice formation processes to...
The RV Ronald H. Brown traveled a section of tropical Atlantic waters northeast of Barbados during January-February 2020 in an international collaboration effort known as Elucidating the Role of Clouds Circulation Coupling in Climate Campaign (EUREC4A). ATOMIC (Atlantic Trade-wind Ocean–Atmosphere Mesoscale Interaction Campaign) was the US contribution to EUREC4A focused...
This paper presents a detailed study of a single thunderstorm anvil cirrus cloud measured on 21 July 2002
near southern Florida during the Cirrus Regional Study of Tropical Anvils and Cirrus Layers–Florida Area
Cirrus Experiment (CRYSTAL-FACE). NASA WB-57F and University of North Dakota Citation aircraft
tracked the microphysical and radiative...
This two-part study attempts to find appropriate mass dimension and terminal velocity relationships that,
when considered together with particle size distributions (PSD), agree with coincident measurements of ice
water content (IWC), and with variables related to higher moments such as the mean mass-weighted fall
speed. Reliable relationships are required for...
The last glacial period exhibited abrupt Dansgaard–Oeschger climatic oscillations, evidence of which is preserved in a variety of Northern Hemisphere palaeoclimate archives¹. Ice cores show that Antarctica cooled during the warm phases of the Greenland Dansgaard–Oeschger cycle and vice versa[superscript 2,3], suggesting an interhemispheric redistribution of heat through a mechanism...
Increasing paleoclimatic evidence suggests that the Little Ice Age (LIA) was a global climate change event. Understanding the forcings and associated climate system feedbacks of the LIA is made difficult by the scarcity of Southern Hemisphere paleoclimate records. We use a new glaciochemical record of a coastal ice core from...
Condensed water content (CWC) measured using a counterflow virtual impactor (CVI) with a Lyman-α hygrometer downstream is compared with that measured by other airborne instruments (a hot-wire probe, a PMS FSSP, and a PMS 2D-C). Results indicate that the CVI system provides a reliable measurement of CWC in both liquid-...
The cause of warming in the Southern Hemisphere during the most recent deglaciation remains a matter of debate[superscript 1,2]. Hypotheses for a Northern Hemisphere trigger, through oceanic redistributions of heat, are based in part on the abrupt onset of warming seen in East Antarctic ice cores and dated to 18,000...
One important role of anthropogenic aerosol particles is their influence on climate by acting as cloud condensation nuclei. However, these particles are diverse in composition and mixing state, and our knowledge of which particle types act as cloud condensation nuclei is incomplete. Here we present direct measurements of individual organic...
A counterflow virtual impactor (CVI) designed for aircraft use was evaluated at the NASA Icing Research Tunnel in Cleveland, Ohio. Tests were conducted for tunnel speeds of 67 and 100 m s⁻¹, for liquid water contents of 0.23–1.4 g m⁻³, and for a wide range of droplet median volume diameters...
Sampling intervals of precipitation geochemistry measurements are often coarser than those required by fine-scale hydrometeorological models. This study presents a statistical method to temporally downscale geochemical tracer signals in precipitation so that they can be used in high-resolution, tracer-enabled applications. In this method, we separated the deterministic component of the...
The knowledge about the intensive agricultural irrigation is very limited, but the use of irrigation is rapidly increasing. As an outcome, the sympathetic ecosystem is accepting modern irrigation that will play an essential function in the present and future for agricultural products. My dissertation will display the modification for investigation...
A counterflow virtual impactor was used to collect residual particles larger than about 0.1 μm diameter from anvil cirrus clouds generated over Florida in the southern United States. A wide variety of particle types were found. About one-third of the nuclei were salts, with varying amounts of crustal material, industrial...
Measurements of ice water content (IWC) and
mean ice-crystal size and concentration made by two in-situ
probes, C, VI and PVM, were compared on the DC-8 aircraft
during SUCCESS flights in orographic ice clouds. The
comparison of 1WC in these wave clouds, that formed at
temperatures of about -38 °C...
Many soil-derived particles dominated by insoluble material, including Saharan dusts, are known to act as ice nuclei. If, however, dust particles can compete with other atmospheric particle types to form liquid cloud droplets, they have a greater potential to change climate through indirect effects on cloud radiative properties and to...
The hydrologic cycle on Earth comprises the transitions among the solid, liquid, and gaseous phases of water. Understanding the hydrologic cycle is of course important for climate science, but also for agricultural, drinking water, and disaster preparedness purposes. Improvements in satellite observations and general circulation models (GCMs) have led to...
Ice crystal larger than about 5 μm diameter were separated from interstitial particles in aircraft contrails and evaporated. Residual particles larger than 0.1 μm were analyzed by electron microscopy. Soot, metals, and volatile organic substances, apparently from the aircraft exhaust, were found. However, the residual particles also contained high percentages...
Summertime low clouds are common in the Pacific Northwest (PNW), but spatiotemporal patterns have not been characterized. We show the first maps of low cloudiness for the western PNW and North Pacific Ocean using a 22‐year satellite‐derived record of monthly mean low cloudiness frequency for May through September and supplemented...
Mineral dust particles have been shown to act as cloud condensation nuclei, and they are known to interact
with developing tropical storms over the Atlantic downwind of the Sahara. Once present within liquid
droplets, they have the potential to act as freezing ice nuclei and further affect the microphysics, dynamics,...
Drought represents an import part of natural hydrologic cycles that govern the rate and transportation of water on global and regional scales. (Trenberth, et al. 2015) Agriculturally, drought represents a threat to crop production and can endanger political and economic stability through the loss of resources and the threat of...
We examine the relation between δ¹⁸O in rainwater collected in southwestern Oregon
and climate variables including temperature, parcel trajectory, precipitation amount, and
specific humidity. Local surface air temperature at the time of sample collection explains a
large proportion of δ¹⁸O variability, suggesting that paleoclimatic archives that are related
to rainfall...
1-km MODIS observations of ship tracks off the west coast of the U.S. are used to characterize changes in cloud visible optical depths, cloud droplet radii, cloud cover fraction, and column cloud liquid water amount as low-level marine clouds respond to particle pollution from underlying ships. This study re-examines the...
Knowledge concerning trade wind cumulus, one of the most dominant cloud types
on the planet, has become increasingly important when considering global issues such as climate change due to their potential influence on the Earth’s energy budget. In this project, using data from the Rain in Cumulus over the Ocean...
During the Ice in Clouds Experiment–Layer Clouds (ICE-L), aged biomass-burning particles were identified within two orographic wave cloud regions over Wyoming using single-particle mass spectrometry and electron microscopy. Using a suite of instrumentation, particle chemistry was characterized in tandem with cloud microphysics. The aged biomass-burning particles comprised ~30%–40% by number...
During the Indian Ocean Experiment (INDOEX), cloud droplets were collected and evaporated using a counterflow virtual impactor (CVI). The nonvolatile residual particles were then analyzed by various instruments. Physical and chemical properties of the below-cloud aerosol to evaluate which aerosol particles act as cloud nuclei in different environments, and their...
The effective radius (r[subscript]e) is a crucial variable in representing the radiative properties of cloud layers in general circulation models. This parameter is proportional to the condensed water content (CWC) divided by the extinction (σ). For ice cloud layers, parameterizations for r[subscript]e have been developed from aircraft in situ measurements...
Ice concentrations in orographic wave clouds at temperatures between −24° and −29°C were shown to be related to aerosol characteristics in nearby clear air during five research flights over the Rocky Mountains. When clouds with influence from colder temperatures were excluded from the dataset, mean ice nuclei and cloud ice...
Amphiphilic gold nanoparticle surfactants can self-assemble at oil-water interfaces to form stable Pickering emulsions. These nanoparticle surfactants have previously been synthesized by functionalizing gold nanoparticles with thiol terminated polyethylene glycol (PEG-thiol), and subsequently with an alkane-thiol. It is necessary to improve the bio-compatibility of the nanoparticles if they are to...
One kilometer Moderate Resolution Imaging Spectroradiometer (MODIS) observations for Terra (morning) and Aqua (afternoon) satellites were used to follow the morning to afternoon evolution of marine stratocumulus clouds that were affected by ship stack exhaust. The observations covered the summer months of 2002-2003 and August 2007 for marine layers off...
Research paper for GEOG323 (Climatology) class describing the effects of physiographic setting, climate elements related to energy, moisture, and pressure and corresponding results on New Zealand's North Island Climate. The paper analyzes major circulation modes, weather patterns and extremes, climate change, and the overall climate type of the region.
Many ecologists and environmental scientists witnessing the scale of current environmental change are becoming increasingly alarmed about how humanity is pushing the boundaries of the Earth’s systems beyond sustainable levels. The world urgently needs global society to redirect itself toward a more sustainable future: one that moves intergenerational equity and...