Naruki Hiranuma

West Texas A&M University | WTAMU · Department of Life, Earth and Environmental Sciences

Prediction of ice formation in clouds presents one of the grand challenges in the atmospheric sciences. Immersion freezing initiated by ice-nucleating particles (INPs) is the dominant pathway of primary ice crystal formation in mixed-phase clouds, where supercooled water droplets and ice crystals coexist, with important implications for the hydrolo...

Ice-nucleating particles (INPs) influence the formation of ice crystals in clouds and many types of precipitation. This study reports unique properties of INPs collected from 42 precipitation samples in the Texas Panhandle region from June 2018 to July 2019. We used a cold stage instrument called the West Texas Cryogenic Refrigerator Applied to Fre...

Atmospheric ice-nucleating particles (INPs) play an important role in determining the phase of clouds, which affects their albedo and lifetime. A lack of data on the spatial and temporal variation of INPs around the globe limits our predictive capacity and understanding of clouds containing ice. Automated instrumentation that can robustly measure I...

The current inadequate understanding of ice nucleating particle (INP) sources in the Arctic region affects the uncertainty in global radiative budgets and in regional climate predictions. In this study, we present atmospheric INP concentrations by offline analyses on samples collected at ground level in Ny-Ålesund (Svalbard), in spring and summer 2...

Ice-nucleating particles (INPs) are an essential class of aerosols found worldwide that have far-reaching but poorly quantified climate feedback mechanisms through interaction with clouds and impacts on precipitation. These particles can have highly variable physicochemical properties in the atmosphere, and it is crucial to continuously monitor the...

Knowledge of chemical composition and mixing state of aerosols at a single particle level is critical for gaining insights into atmospheric processes. One common tool to make these measurements is single particle mass spectrometry. There remains a need to compare the performance of different single particle mass spectrometers (SPMSs). An intercompa...

The West Texas A&M University Microfluidic Static Droplet Array (WT-MFSDA) platform was developed for studying atmospheric ice nucleation, specifically immersion freezing. It combines a microfluidic device with interconnected droplet parking traps and a unique hand pipetting method to create an array of nanoliter-sized droplets containing ice-nucle...

Ice-nucleating particles (INPs) are an important class of aerosols found worldwide that have far-reaching but poorly quantified climate feedback mechanisms through interaction with clouds and impacts on precipitation. These particles can have highly variable physicochemical properties in the atmosphere, and it is vital to measure their concentratio...

Ice-nucleating particles (INPs) initiate primary ice formation in Arctic mixed-phase clouds (MPCs), altering cloud radiative properties and modulating precipitation. For atmospheric INPs, the complexity of their spatiotemporal variations, heterogeneous sources, and evolution via intricate atmospheric interactions challenge the understanding of thei...

We assess the predictability of immersion-mode ice nucleating particles (INPs) at a remote marine site in the Eastern North Atlantic (ENA) using aerosol simulations from a global climate model as inputs to the immersion-mode INP parameterizations. While the model- simulated INP concentrations are lower by one to three orders of magnitudes compared...

This paper introduces hands-on curricular modules integrated with research in atmospheric ice nucleation, which is an important phenomenon potentially influencing global climate change. The primary goal of this work is to promote meaningful laboratory exercises to enhance the competence of students in the fields of science, technology, engineering,...

Ice nucleating particles (INPs) initiate primary ice formation in Arctic mixed-phase clouds, altering cloud radiative properties and modulating precipitation. For atmospheric INPs, the complexity of their spatiotemporal variations, heterogeneous sources and evolution via intricate atmospheric interactions challenge the understanding of their impact...

In this study, we present atmospheric ice-nucleating particle (INP) concentrations from the Gruvebadet (GVB) observatory in Ny-Ålesund (Svalbard). All aerosol particle sampling activities were conducted in April–August 2018. Ambient INP concentrations (nINP) were measured for aerosol particles collected on filter samples by means of two offline ins...

In this work, an abundance of ice-nucleating particles (INPs) from livestock facilities was studied through laboratory measurements from cloud-simulation chamber experiments and field investigation in the Texas Panhandle. Surface materials from two livestock facilities, one in the Texas Panhandle and another from McGregor, Texas, were selected as d...

Glaciation in mixed-phase clouds predominantly occurs through the immersion-freezing mode where ice-nucleating particles (INPs) immersed within supercooled droplets induce the nucleation of ice. Model representations of this process currently are a large source of uncertainty in simulating cloud radiative properties, so to constrain these estimates...

This study presents a comprehensive investigation of ice-nucleating particles (INPs) in the surface materials and aerosol 20 particles from U.S. cattle feeding facilities. Using a modern suite of online and offline aerosol particle characterization instruments, we conducted a three-year field survey (2016-2019), Aerosol Interaction and Dynamics in...

We present our field results of ice-nucleating particle (INP) measurements from the commercialized version of the Portable Ice Nucleation Experiment (PINE) chamber from two different campaigns. Our first field campaign, TxTEST, was conducted at West Texas A&M University (July–August 2019), and the other campaign, ExINP-SGP, was held at the Atmosphe...

This study considers how feedlot dust size and composition contribute to atmosphericice nucleation and the formation of local cloud and precipitation in the Texas Panhandle. [...]

Quantifying the impact of complex organic particles on the formation of ice crystals in clouds remains challenging, mostly due to the vast number of different sources ranging from sea spray to agricultural areas. In particular, there are many open questions regarding the ice nucleation properties of organic particles released from terrestrial sourc...

Atmospheric ice-nucleating particles (INP) play an important role in determining the phase of clouds, which affects their albedo and lifetime. A lack of data on the spatial and temporal variation of INPs around the globe limits our predictive capacity and understanding of clouds containing ice. Automated instrumentation that can robustly measure IN...

EGU2020 Sharing Geoscience Online - the PINE presentation video available - if you have any comments, please post directly on the following web. https://meetingorganizer.copernicus.org/EGU2020/EGU2020-12385.html

Abstract. Glaciation in mixed-phase clouds predominately occurs through the immersion freezing mode where ice nucleating particles (INPs) immersed within supercooled droplets induce nucleation of ice. Currently, model representations of this process are a large source of uncertainty in simulating cloud radiative properties, and to constrain these e...

Abstract: We present our first laboratory calibration and field results of a newly developed commercial ice nucleation chamber, the so-called PINE. The PINE instrument is developed based on the design of the AIDA cloud chamber (Möhler et al., 2003) to advance online atmospheric ice nucleation research. A unique aspect of the PINE chamber includes i...

Abstract. Quantifying the impact of complex organic particles on the formation of ice crystals in clouds remains challenging, mostly due to the vast number of different sources ranging from sea spray to agricultural areas. In particular, there are many open questions regarding the ice nucleation properties of organic particles released from terrest...

We present the laboratory results of immersion freezing efficiencies of cellulose particles at supercooled temperature (T) conditions. Three types of chemically homogeneous cellulose samples are used as surrogates that represent supermicron and submicron ice-nucleating plant structural polymers. These samples include microcrystalline cellulose (MCC...

Supplement of A comprehensive characterization of ice nucleation by three different types of cellulose particles immersed in water Naruki Hiranuma et al. Correspondence to: Naruki Hiranuma (nhiranuma@wtamu.edu) and Ottmar Möhler (ottmar.moehler@kit.edu)

Biological particles, including bacteria and bacterial fragments, have been of much interest due to the special ability of some to nucleate ice at modestly supercooled temperatures. This paper presents results from a recent study conducted on two strains of cultivated bacteria which suggest that bacterial fragments mixed with agar, and not whole ba...

The second phase of the Fifth International Ice Nucleation Workshop (FIN-02) involved the gathering of a large number of researchers at the Karlsruhe Institute of Technology's Aerosol Interactions and Dynamics of the Atmosphere (AIDA) facility to promote characterization and understanding of ice nucleation measurements made by a variety of methods...

The second phase of the Fifth International Ice Nucleation Workshop (FIN-02) involved the gathering of a large number of researchers at the Karlsruhe Institute of Technology's Aerosol Interactions and Dynamics of the Atmosphere (AIDA) facility to promote characterization and understanding of ice nucleation measurements made by a variety of methods...

We present the laboratory results of immersion freezing efficiencies of cellulose particles at supercooled temperature (T) conditions. Three types of chemically homogeneous cellulose samples are used as surrogates that represent supermicron and submicron ice nucleating plant structural polymers. These samples include micro-crystalline cellulose (MC...

The second phase of the Fifth International Ice Nucleation Workshop (FIN-02) involved the gathering of a large number of researchers at the Karlsruhe Institute of Technology's Aerosol Interactions and Dynamics of the Atmosphere (AIDA) facility to promote characterization and understanding of ice nucleation measurements made by the variety of method...

Biological particles, including bacteria and bacterial fragments, have been of much interest due to the special ability of some to nucleate ice at modestly low temperatures. This paper presents results from a recent study conducted on two strains of cultivated bacteria which suggest that bacterial fragments mixed with agar, and not whole bacterial...

One of the top environmental concerns of the world today is air pollution, which is affecting our health every day (Bickerstaff & Walker, 2001). Studies have shown that air pollution has a major effect in human health by increasing sickness and death (Dockery, & Pope III, 1994). A major form of air pollution is aerosol; scientists describe it as ti...

Agricultural dust particles from animal feeding operations have been long known to affect regional air quality in the Texas Panhandle. In particular, housing roughly one-third of the nation’s cattle, open-air feedlots within 100 miles of West Texas A&M University (WTAMU) represent a significant source of dust particles. Our previous studies show th...

Based on results of 11 yr of heterogeneous ice nucleation experiments at the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) chamber in Karlsruhe, Germany, a new empirical parameterization framework for heterogeneous ice nucleation was developed. The framework currently includes desert dust and soot aerosol and quantifies the ice nucleati...

Separation of particles that play a role in cloud activation and ice nucleation from interstitial aerosols has become necessary to further understand aerosol-cloud interactions. The pumped counterflow virtual impactor (PCVI), which uses a vacuum pump to accelerate the particles and increase their momentum, provides an accessible option for dynamic...

Separation of particles that play a role in cloud activation and ice nucleation from interstitial aerosols has become necessary to further understand aerosol-cloud interactions. The pumped counterflow virtual impactor (PCVI), which uses a vacuum pump to accelerate the particles and increase their momentum, provides an accessible option for dynamic...

Increasing evidence of the high diversity and efficient freezing ability of biological ice-nucleating particles is driving a reevaluation of their impact upon climate. Despite their potential importance, little is known about their atmospheric abundance and ice nucleation efficiency, especially non-proteinaceous ones, in comparison to non-biologica...

Immersion freezing is the most relevant heterogeneous ice nucleation mechanism through which ice crystals are formed in mixed-phase clouds. In recent years, an increasing number of laboratory experiments utilizing a variety of instruments have examined immersion freezing activity of atmospherically relevant ice-nucleating particles. However, an int...

Ice particles in the atmosphere influence clouds, precipitation and climate, and often form with help from aerosols that serve as ice-nucleating particles. Biological particles1, including non-proteinaceous ones2,3, contribute to the diverse spectrum of ice-nucleating particles4,5. However, little is known about their atmospheric abundance and ice...

Seven different instruments and measurement methods were used to examine the immersion freezing of bacterial ice nuclei from Snomax® (hereafter Snomax), a product containing ice-active protein complexes from nonviable Pseudomonas syringae bacteria. The experimental conditions were kept as similar as possible for the different measurements. Of the p...

A new heterogeneous ice nucleation parameterization that covers a wide temperature range (−36 to −78 °C) is presented. Developing and testing such an ice nucleation parameterization, which is constrained through identical experimental conditions, is critical in order to accurately simulate the ice nucleation processes in cirrus clouds. The surface-...

A new heterogeneous ice nucleation parameterization that covers a wide temperature range (−36 to −78 °C) is presented. Developing and testing such an ice nucleation parameterization, which is constrained through identical experimental conditions, is important to accurately simulate the ice nucleation processes in cirrus clouds. The ice nucleation a...

Immersion freezing is the most relevant heterogeneous ice nucleation mechanism through which ice crystals are formed in mixed-phase clouds. In recent years, an increasing number of laboratory experiments utilizing a variety of instruments have examined immersion freezing activity of atmospherically relevant ice nucleating particles (INPs). However,...

Biological aerosol particles have recently been accentuated by their efficient ice nucleating activity as well as potential impact on clouds and global climate. Despite their potential importance, little is known about the abundance of biological particles in the atmosphere and their role compared to non-biological material and, consequently, their...

In this paper, the effect of the morphological modi-fication of aerosol particles with respect to heterogeneous ice nucleation is comprehensively investigated for laboratory-generated hematite particles as a model substrate for at-mospheric dust particles. The surface-area-scaled ice nucle-ation efficiencies of monodisperse cubic hematite particles...

In this paper, the effect of the morphological modification of aerosol particles with respect to heterogeneous ice nucleation is comprehensively investigated for laboratory-generated hematite particles as a model substrate for atmospheric dust particles. The surface area-scaled ice nucleation efficiencies of monodisperse cubic hematite particles an...

Ambient particles and the dry residuals of mixed-phase cloud droplets and ice crystals were collected during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) near Barrow, Alaska, in spring of 2008. The collected particles were analyzed using Computer Controlled Scanning Electron Microscopy with Energy Dispersive X-ray analysis and Scanning Tra...

Ambient particles and the dry residuals of mixed-phase cloud droplets and ice crystals were collected during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) near Barrow, Alaska, in spring of 2008. The collected particles were analyzed using Computer Controlled Scanning Electron Microscopy with Energy Dispersive X-ray analysis and Scanning Tra...

The immersion mode ice nucleation efficiency of clay minerals and biological aerosols has been investigated using the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber. Both monodisperse and polydisperse populations of (1) various clay dust samples as well as (2) Snomax ® (a proxy for bacterial ice nucleators) and (3) hematite...

The Immersion mode ice nucleation efficiency of clay minerals as well as Snomax has been investigated using the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber in the temperature range between -C and -3C. We observed the temperature is a major driver of immersion mode ice nucleation with a minor contribution of time dependen...

The immersion mode ice nucleation efficiency of clay minerals and biological aerosols has been investigated using the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber. Both monodisperse and polydisperse populations of (1) various clay dust samples as well as (2) Snomax® (a proxy for bacterial ice nucleators) and (3) hematite...

Since 2003, the AIDA cloud chamber has been used for comprehensive series of ice nucleation experiments with a variety of different aerosols and in wide ranges of temperature, relative humidity and cooling rate. Ice nucleation onset and ice formation rates have been obtained as a function of aerosol parameters, ice supersaturation, temperature a...

The immersion mode ice nucleation efficiency of clay minerals was investigated using the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber. Both monodisperse and polydisperse populations of various clay dust samples as well as hematite and Snomax were examined in the temperature range between -4 ˚C and -35 ˚C. We observed the...

The organic functional group composition of particles produced in laboratory “smog” chambers were characterized by scanning transmission X-ray microscopy (STXM) with near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and characteristic spectral signatures for secondary organic aerosol (SOA) were identified. The main objective of this s...

Substantial uncertainties still exist in the scientific understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transfor-mation of atmospheric aerosol and the resulting impact on climate change. The US Department of Energy (DOE) Atmo-spheric Radiation Measurement (ARM) program's Carbona-ceous...

A large fraction of submicron atmospheric aerosol particles contains both organic material and inorganic salts. As the relative humidity cycles in the atmosphere and the water content of the particles correspondingly changes, these mixed particles can undergo a range of phase transitions, possibly including liquid-liquid phase separation. If liquid...

Organonitrate (ON) groups are thought to be important substituents in secondary organic aerosols (SOAs). Model simulations and laboratory studies indicate a large fraction of ON groups in aerosol particles, but much lower quantities are observed in the atmosphere. Hydrolysis of ON groups in aerosol particles has been proposed recently to account fo...

Substantial uncertainties still exist in the scientific understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transformation of atmospheric aerosol and the resulting impact on climate change. The US Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program's Carbonaceous Aer...

The influence of relative humidity on the yield, chemical composition, and cloud condensation nucleus (CCN) activity of a-pinene secondary organic aerosol (SOA) particles has been investigated as a function of SOA mass loading. Internally mixed SOA particles were generated by the condensation of organic molecules onto ammonium sulfate particles dur...

Droplets produced in a cloud condensation nucleus chamber as a function of supersaturation have been separated from unactivated aerosol particles using counterflow virtual impaction. Residual material after droplets were evaporated was chemically analyzed with an Aerodyne Aerosol Mass Spectrometer and the Particle Analysis by Laser Mass Spectrometr...

This study focuses on the characterization of cloud condensation nuclei (CCN) activity of aerosol particles measured during the Carbonaceous Aerosols and Radiative Effects Study (CARES) near Sacramento, CA in June 2010. Supersaturation-dependant CCN activity ( 0.1 - 0.5% supersaturation) was measured with commercial CCN counters at two locations; o...

Housing roughly 10 million head of cattle in the United States alone, open air cattle feedlots represent a significant but poorly constrained source of atmospheric particles. Here we present a comprehensive characterization of physical and chemical properties of particles emitted from a large representative cattle feedlot in the Southwest United St...

Housing roughly 10 million head of cattle in the United States alone, open air cattle feedlots represent a significant but poorly constrained source of atmospheric particles. Here we present a comprehensive characterization of physical and chemical properties of particles emitted from a large representative cattle feedlot in the Southwest United St...

Droplets produced in a cloud condensation nucleus chamber as a function of supersaturation have been separated from unactivated aerosol particles using counterflow virtual impaction. Residual material after droplets were evaporated was chemically analyzed with an Aerodyne Aerosol Mass Spectrometer and the Particle Analysis by Laser Mass Spectrometr...

While it has been shown that aerosol size has a direct correlation with its ability to act as an ice nucleus, the role of the composition of freshly emitted and evolving aerosol in nucleation is poorly understood. Here we use combined measurements of ice nucleation and high resolution single particle composition to provide insight on the connection...

During the June, 2010 Carbonaceous Aerosol and Radiative Effects Study (CARES) a custom made humidity controlled nephelometer, hereafter termed a `humidograph', was deployed with a commercial cloud condensation nucleus counter (CCNC) and the particle analysis by laser mass spectrometry (PALMS) instrument. Other ancillary measurements, such as parti...

This study focuses on the characterization of cloud condensation nuclei (CCN) properties of aerosol particles measured during the Carbonaceous Aerosols and Radiative Effects Study (CARES) near Sacramento, CA in June 2010. Supersaturation-dependant CCN activity (0.07 - 0.5% supersaturation) was measured with DMT CCN counters at two locations; one ne...

Extensive aerosol optical properties, particle size distributions, and Aerodyne quadrupole aerosol mass spectrometer measurements collected during TRAMP/TexAQS 2006 were examined in light of collocated meteorological and chemical measurements. Much of the evident variability in the observed aerosol-related air quality is due to changing synoptic me...

Mixing ratios of total and gaseous ammonia were measured at an open-air cattle feeding facility in the Texas Panhandle in the summers of 2007 and 2008. Samples were collected at the nominally upwind and downwind edges of the facility. In 2008, a series of far-field samples was also collected 3.5 km north of the facility. Ammonium concentrations wer...

Agricultural fugitive dust and odor are significant sources of localized air pollution in the semi-arid southern Great Plains. Daily episodes of ground-level fugitive dust emissions from the cattle feedlots associated with increased cattle activity in the early evenings are routinely observed, while consistently high ammonia is observed throughout...

A field study at a cattle feedlot in the Texas Panhandle was conducted to characterize the hygroscopic, morphological, and chemical properties of agricultural aerosols and to identify possible correlations between these properties. To explore the hygroscopic nature of the agricultural particles, we have collected size-resolved aerosol samples using...

"August 2005." "(Naruki Hiranuma)." Thesis (M.S.)--West Texas A&M University, 2005. Includes bibliographical references (leaves 87-92). System requirements for CD-ROM: SPSS (unknown version) and Microsoft Excel.

Agricultural fugitive dust is a significant source of localized air pollution in the semi-arid southern Great Plains. In the Texas Panhandle, daily episodes of ground-level fugitive dust emissions from the cattle feedlots are routinely observed in conjunction with increased cattle activity in the late afternoons and early evenings. We conducted a f...

Open-lot, concentrated animal feeding operations (CAFOs) in the southern High Plains, such as cattle feedyards and open-lot dairies, generate fugitive emissions of particulate matter that occasionally reduce downwind visibility. The long-path visibility transmissometer (LPV) is used to measure total atmospheric extinction, a direct measure of path-...

We are adapting the long-path visibility transmissometer (model LPV-2/3, Optec, Inc., Lowell, MI) as a line-integrating, surrogate measurement for agricultural particulate matter where the source of the particulate matter, and therefore its "extinction behavior" as a function of mass concentration, is known with confidence. We report herein on our...