Ratio Of Snow Research Articles

The importance of blowing snow to halogen-containing aerosol in coastal Antarctica: influence of source region versus wind speed

Abstract. A fundamental understanding of the processes that control Antarctic aerosols is necessary in determining the aerosol impacts on climate-relevant processes from Antarctic ice cores to clouds. The first in situ observational online composition measurements by an aerosol mass spectrometer (AMS) of Antarctic aerosols were only recently performed during the Two-Season Ozone Depletion and Interaction with Aerosols Campaign (2ODIAC). 2ODIAC was deployed to sea ice on the Ross Sea near McMurdo Station over two field seasons: austral spring–summer 2014 and winter–spring 2015. The results presented here focus on the overall trends in aerosol composition primarily as functions of air masses and local meteorological conditions. The results suggest that the impact of long-range air mass back trajectories on either the absolute or relative concentrations of the aerosol constituents measured by (and inferred from) an AMS at a coastal location is small relative to the impact of local meteorology. However, when the data are parsed by wind speed, two observations become clear. First, a critical wind speed is required to loft snow from the surface, which, in turn, increases particle counts in all measured size bins. Second, elevated wind speeds showed increased aerosol chloride and sodium. Further inspection of the AMS data shows that the increased chloride concentrations have more of a “fast-vaporizing” nature than chloride measured at low wind speed. Also presented are the Cl:Na ratios of snow samples and aerosol filter samples, as measured by ion chromatography, as well as non-chloride aerosol constituents measured by the AMS. Additionally, submicron aerosol iodine and bromine concentrations as functions of wind speed are also presented. The results presented here suggest that aerosol composition in coastal Antarctica is a strong function of wind speed and that the mechanisms determining aerosol composition are likely linked to blowing snow.

Insight Into Radio‐Isotope 129I Deposition in Fresh Snow at a Remote Glacier Basin of Northeast Tibetan Plateau, China

AbstractWe present data of 129I deposition in fresh snow in the Laohugou glacier basin, northeast Tibetan Plateau, in summer 2016 and 2017, and trace its source and elevational distribution in the troposphere. Our results show that the 129I/127I atomic ratios in the fresh snow on the glacier surface are about 2 orders of magnitude larger than those in the Antarctic fresh snow and 4 orders the prenuclear level, indicating a predominantly anthropogenic source of the 129I in the mountain glacier environment of northeast Tibetan Plateau. The 129I level in the Laohugou glacier basin is 1–2 orders of magnitude lower than at representative European locations, and not significantly higher than that observed at other sites in Asia. The 129I/127I atomic ratio and 129I level show clear increases with elevation from 4,300 to 5,100 m above sea level. The 129I in the Laohugou glacier basin is probably deposited from the upper troposphere where there exists a local maximum of 129I. A conceptual model for interpretation of the observed 129I concentration and profile in Laohugou is provided. Thus, this work is of importance in providing a more complete view on the transport, dispersion, and removal of 129I in the atmosphere.

Determination of Osmium Concentration and Isotope Composition at Ultra-low Level in Polar Ice and Snow.

Here we use two chemical separation procedures to determine exceptionally low Os concentrations (∼10-15 g g-1) and Os isotopic composition in polar snow/ice. Approximately 50 g of meltwater is spiked with 190Os tracer solution and frozen at -20 °C in quartz-glass ampules. A mixture of H2O2 and HNO3 is then added, and the sample is heated to 300 °C at 100 bar. This allows tracer Os to be equilibrated with the sample as all Os species are oxidized to OsO4. The resulting OsO4 is separated using either distillation (Method-I) or solvent-extraction (Method-II), purified, and measured using negative thermal ionization mass spectrometry (N-TIMS). A new technique is presented that minimizes Re and Os blanks of the Pt filaments used in N-TIMS. We analyze snow collected from Summit, Greenland during 2009, 2014, and 2017. We find that the average Os concentration of the snow is 0.459 ± 0.018 (95% C.I.) fg g-1 corresponding to an Os flux of 0.0579 ± 0.0023 (95% C.I.) fmol cm-2 yr-1. The average R(187Os/188Os) ratio of the Summit snow is 0.264 ± 0.026 (95% C.I.). Assuming that the volcanic source is negligible, the average ratio indicates that about 0.0518 ± 0.0040 (95% C.I.) fmol cm-2 yr-1 of Os is of cosmic derivation, corresponding to an accretion rate of extra-terrestrial Os to the Earth of 264 ± 21 mol yr-1.

The effect of ice nuclei on a deep convective cloud in South China

This study uses the Weather Research and Forecasting Model to simulate a deep convective cloud under a relatively polluted condition in South China. Ice nuclei (IN) aerosols near the surface are effectively transported upwards to above the 0 °C level by the strong updrafts in the convective cloud. Four cases with initial surface IN aerosol concentrations of 1, 10, 100, and 1000 L−1 are simulated. All simulations can well reproduce the major characteristics of the deep convective cloud in terms of the evolution, spatial distribution, and its track. IN aerosols have little effect on these macrophysical characteristics but can significantly affect ice formation. When IN concentration is increased, all heterogeneous nucleation modes are significantly enhanced, whereas the homogeneous freezing of cloud droplets is unchanged or weakened depending on the IN concentration and the development stages of the deep convective cloud. The homogeneous freezing of haze particles is generally not affected by increased IN but is slightly weakened in the extremely high IN case. As IN concentration is increased by 10 and 100 times, the enhanced heterogeneous nucleation is still not strong enough to compete with homogeneous freezing. Ice formation is hence still dominated by the homogenous freezing of cloud droplets and haze particles in the layer of 9–14 km, where most of the ice crystals are produced. The microphysical properties are generally unaffected in all the stages of cloud evolution. As IN concentration is increased by 1000 times and heterogeneous nucleation is further enhanced, the homogeneous freezing of cloud droplets and haze particles dominates only in the mature and dissipating stages, leading to unaffected ice number mixing ratio in the anvil region (approximately above 9 km) for these two stages. However, in the developing stage, when the supply of cloud droplets is limited, the homogeneous freezing of cloud droplets is weakened or even suppressed due to the very strong competition for liquid water with heterogeneous nucleation, leading to significantly lower ice number mixing ratio in the anvil regions. In addition, the microphysical properties in the convective core regions below the cloud anvil (approximately below 9 km) are also affected in the case of 1000 L−1. The enhanced heterogeneous nucleation produces more ice crystals below 9 km, leading to a stronger conversion from ice crystals to snow particles, and hence higher number and mass mixing ratios of snow. The IN effect on the spatial distributions and temporal evolutions of the surface precipitation and updraft velocity is generally insignificant.

Review of Black Carbon in the Arctic—Origin, Measurement Methods, and Observations

Current knowledge about black carbon (BC) emission estimates, state-of-the-art measurement methods, near-surface BC concentrations ([BC]), and mixing ratios in snow is consolidated for the Arctic. Since no direct method exists to measure [BC], results from modern indirect methods differ among devices. Pan-Arctic wide [BC] and changes are hard to access; monitoring often ends once national ambient air quality standards are met. Few remote sites have long records. Past measurements showed distinct differences among the various Arctic climate regions. Past and own observations in communities permit qualitative discussion of the diurnal course, response to weather, season, or different emission situations like weekdays and weekends at a given site and/or among sites. Comparison of data from collocated aethalometer indicated more similar accuracy than found in mid- and low-latitudes despite of much lower ambient temperatures and [BC]. Snow samples give an incomplete glimpse at the removal and input into ecosystems.

Pb/Cd Ratios in Fresh Snow Derived from Cold Air Mass from Northern North Eastern China and Russian Maritime Province along the Coast of the Japan Sea in Honshu Island and a Long-range Transport Mechanism during Winter

粗大粒子の影響を避けるために近隣の地方工業都市から15 km以上離れた遠隔地において降雪・雨の試料を採取した．2014年及び2015年に日本の本州日本海沿いの遠隔地で採取した新雪中のPbとCdの濃度を2010，2014及び2015年に四国の遠隔地で採取された新雪と降雨試料中の濃度と共に報告した．降雪または降雨中の大気塊の起源は後方流跡線上の24時間前の位置から推定した．PbとCdの相関関係から北東中国の黒竜江省?極東ロシア（沿海地方）からの寒気塊に原因した降雪中では[Pb]/[Cd]＝27.4±2.8（R2＝0.979）が得られた．日本起源の場合の降水では[Pb]/[Cd]＝2.8±0.4（R2＝0.732）であった．PbとCdの発生地域を推定できる方法を提案した．中国華北，北東中国南部，朝鮮半島，北東中国北部?沿海地方，日本を起源にもつ大気に対するPb-Cd二元系相関図に本州での雪試料中の（[Pb], [Cd]）をプロットすることで，最も近くの回帰直線を示す地域を発生域に帰属した．無機小球形粒子（φ 1～3 μm）と硫酸塩としてのPbとCdを含むエアロゾル（φ 0.5±0.4 μm）の長距離輸送機構の相違が原因して，両者をトレーサーに用いて帰属した大気塊の起源が相互に異なるケースがあった．その相違は，降雪時間帯の後方流跡線の変動により説明できた．

Dynamic downscaling over western Himalayas: Impact of cloud microphysics schemes

Due to lack of observation data in the region of inhomogeneous terrain of the Himalayas, detailed climate of Himalayas is still unknown. Global reanalysis data are too coarse to represent the hydroclimate over the region with sharp orography gradient in the western Himalayas. In the present study, dynamic downscaling of the European Centre for Medium-Range Weather Forecast (ECMWF) Reanalysis-Interim (ERA-I) dataset over the western Himalayas using high-resolution Weather Research and Forecast (WRF) model has been carried out. Sensitivity studies have also been carried out using convection and microphysics parameterization schemes. The WRF model simulations have been compared against ERA-I and available station observations. Analysis of the results suggests that the WRF model has simulated the hydroclimate of the region well.It is found that in the simulations that the impact of convection scheme is more during summer months than in winter. Examination of simulated results using various microphysics schemes reveal that the WRF single-moment class-6 (WSM6) scheme simulates more precipitation on the upwind region of the high mountain than that in the Morrison and Thompson schemes during the winter period. Vertical distribution of various hydrometeors shows that there are large differences in mixing ratios of ice, snow and graupel in the simulations with different microphysics schemes. The ice mixing ratio in Morrison scheme is more than WSM6 above 400hPa. The Thompson scheme favors formation of more snow than WSM6 or Morrison schemes while the Morrison scheme has more graupel formation than other schemes.

Toward mountains without permanent snow and ice

The cryosphere in mountain regions is rapidly declining, a trend that is expected to accelerate over the next several decades due to anthropogenic climate change. A cascade of effects will result, extending from mountains to lowlands with associated impacts on human livelihood, economy, and ecosystems. With rising air temperatures and increased radiative forcing, glaciers will become smaller and, in some cases, disappear, the area of frozen ground will diminish, the ratio of snow to rainfall will decrease, and the timing and magnitude of both maximum and minimum streamflow will change. These changes will affect erosion rates, sediment, and nutrient flux, and the biogeochemistry of rivers and proglacial lakes, all of which influence water quality, aquatic habitat, and biotic communities. Changes in the length of the growing season will allow low‐elevation plants and animals to expand their ranges upward. Slope failures due to thawing alpine permafrost, and outburst floods from glacier‐ and moraine‐dammed lakes will threaten downstream populations. Societies even well beyond the mountains depend on meltwater from glaciers and snow for drinking water supplies, irrigation, mining, hydropower, agriculture, and recreation. Here, we review and, where possible, quantify the impacts of anticipated climate change on the alpine cryosphere, hydrosphere, and biosphere, and consider the implications for adaptation to a future of mountains without permanent snow and ice.

Large‐scale teleconnection patterns and synoptic climatology of major snow‐avalanche winters in the Presidential Range (New Hampshire, USA)

ABSTRACTThe relationships between the synoptic climatology, large‐scale teleconnections and the regional avalanche activity index (RAAI) inferred from tree‐rings were evaluated for the Presidential Range in the White Mountains (New Hampshire, USA). During the period 1936–2012, 18 years of regional avalanche activity were compared with the winter‐scale prevailing joint temperature/climatic modes (cold/wet (CW), cold/dry (CD), warm/wet (WW) and warm/dry (WW)), the North Atlantic Oscillation (NAO), the El Niño‐Southern Oscillation (ENSO), the 500‐mbar composite anomaly maps and the ratio of snow from different storm tracks. The total winter snowfall and the NAO negatively correlate with the RAAI. There is also a significant difference in avalanche activity between winters with a NAO under or above −3. Winters of regional avalanche activity were present in the four climatic modes, albeit the ratio of avalanche/non‐avalanche years is superior for CW winters compared to the three other modes, as well as for wet winters compared to dry winters. CW, CD and WW winters exhibit a negative NAO anomaly, which is eastbound for the wet years. Cold winters (CW, CD) receive more snow from the Great Lakes, whereas coastal depressions are more important during wet winters (CW, WW). The NAO is an adequate predictor of snowfall, but does not provide information about the storm tracks. On the contrary, the ENSO is poorly correlated with snowfall, but its relationship is significant with the ratio of snow produced by coastal depressions (positive relationship) and Great Lakes storms (negative relationship). These are the first results quantifying the atmospheric circulation – synoptic meteorology – snow avalanche relationships in Northeastern North America.

Determination of the isotopic composition of sub-ng amounts of Sr in Antarctic snow by multi-collector ICP-mass spectrometry

Determination of the87Sr/86Sr isotope ratio in Antarctic snow by multi-collector ICP-MS can provide useful information on the sources of the atmospheric particulates in present and ancient times.

Characteristics of the ratios of snow, rain and sleet to precipitation on the Qinghai-Tibet Plateau during 1961–2014

Precipitation in different types has great influence not only on water resources and distribution of annual precipitation in cold regions, but also on the thermal regimes of frozen ground. The long-term variations of the ratios of snow, rain and sleet to precipitation were analyzed in this study. The 44 meteorological stations were selected, which are located on the Qinghai-Tibet Plateau (QTP) including permafrost and seasonal frozen ground regions. The results indicate that the monthly snow/precipitation ratio in permafrost regions is far higher than that in seasonal frozen ground regions, but the monthly rain/precipitation ratio in permafrost regions is lower than that in seasonal frozen ground regions, and the monthly variation of sleet/precipitation ratio is indistinctive. The annual ratios of snow and sleet to precipitation show decreasing trends in both regions, and annual rain/precipitation ratio shows an increasing tendency. The dropping magnitude of annual snow/precipitation ratio in seasonal frozen ground regions is larger than that in permafrost regions. The maximum and minimum annual snow/precipitation ratios in both regions occur in winter and summer, respectively, and the second is in spring, instead, the maximum and minimum annual rain/precipitation ratios appear in summer and winter, respectively. The spatial features of the ratios of snow and rain to precipitation are largely opposite, that is, the low snow/precipitation ratio stations are usually associated with the high rain/precipitation ratio, and prominent seasonal diversities of three ratios can be found from their spatial patterns. In addition, the decreasing (increasing) tendency of snow (rain)/precipitation ratio in spring and autumn is more significant than that in winter and summer, and these stations of snow/precipitation ratio with downward trends are mainly located at the edge of the QTP. The ratios of snow and sleet to precipitation will gradually decrease (increase), and the rain/precipitation ratio will increase (decrease) with the air temperature (altitude) rises, respectively, while there are significant seasonal discrepancies. Moreover, the altitude zone showing remarkable variations of the ratios of snow and rain to precipitation ranges from 3000 to 4000 m a.s.l, especially in spring and summer.

Climate anomalies associated with the occurrence of rockfalls at high-elevation in the Italian Alps

Abstract. Climate change is seriously affecting the cryosphere in terms, for example, of permafrost thaw, alteration of rain ∕ snow ratio, and glacier shrinkage. There is concern about the increasing number of rockfalls at high elevation in the last decades. Nevertheless, the exact role of climate parameters in slope instability at high elevation has not been fully explored yet. In this paper, we investigate 41 rockfalls listed in different sources (newspapers, technical reports, and CNR IRPI archive) in the elevation range 1500–4200 m a.s.l. in the Italian Alps between 1997 and 2013 in the absence of an evident trigger. We apply and improve an existing data-based statistical approach to detect the anomalies of climate parameters (temperature and precipitation) associated with rockfall occurrences. The identified climate anomalies have been related to the spatiotemporal distribution of the events. Rockfalls occurred in association with significant temperature anomalies in 83 % of our case studies. Temperature represents a key factor contributing to slope failure occurrence in different ways. As expected, warm temperatures accelerate snowmelt and permafrost thaw; however, surprisingly, negative anomalies are also often associated with slope failures. Interestingly, different regional patterns emerge from the data: higher-than-average temperatures are often associated with rockfalls in the Western Alps, while in the Eastern Alps slope failures are mainly associated with colder-than-average temperatures.

Lead fluxes and 206Pb/207Pb isotope ratios in rime and snow collected at remote mountain-top locations (Czech Republic, Central Europe): Patterns and sources

During three winter seasons (2009–2011), Pb concentrations were measured in precipitation at 10 high-elevation sites in the Czech Republic, close to the borders with Austria, Germany, Poland, and Slovakia. Soluble and insoluble Pb forms were quantified in snow (vertical deposition), and rime (horizontal deposition). The objective was to compare Pb input fluxes into ecosystems via vertical and horizontal deposition, and to identify the residual Pb pollution sources in an era of rapidly decreasing industrial pollution. Lead soluble in diluted HNO3 made up 96% of total Pb deposition, with the remaining 4% Pb bound mainly in silicates. Three times higher concentrations of soluble Pb in rime than in snow, and 2.5 times higher concentrations of insoluble Pb in rime than in snow were associated with slightly different Pb isotope ratios. On average, the 206Pb/207Pb ratios in rime were higher than those in snow. Higher mean 206Pb/207Pb ratios of insoluble Pb (1.175) than in soluble Pb (1.165) may indicate an increasing role of geogenic Pb in recent atmospheric deposition. A distinct reversal to more radiogenic 206Pb/207Pb ratios in snow and rime in 2010, compared to literature data from rain-fed Sphagnum peatlands (1800–2000 A.D.), documented a recent decrease in anthropogenic Pb in the atmosphere of Central Europe. Since the early 1980s, Pb concentrations in snow decreased 18 times in the rural south of the Czech Republic, but only twice in the industrial north of the Czech Republic. Isotope signatures indicated that Pb in today's atmospheric deposition is mainly derived from Mesozoic ores mined/processed in Poland and coal combustion in the Czech Republic and Poland.

Effects of Mixed Phase Microphysical Process on Precipitation in a Simulated Convective Cloud

The effects of the liquid water content (LWC) and mixing ratio of hydrometeors in the simulation of convective precipitation in Wuhan, Hubei Province, China, are investigated using a three-dimensional convective rainstorm model. The microphysical processes of warm and cold clouds are considered into microphysical parameterization. The warm-cloud process is dominated by the combined effects of condensation and drop coalescence. The cold-cloud process is initiated mainly by production of graupel, and the microphysical parameterizations are used to predict the mixing ratio of cloud droplets, rain, ice crystals, snow, and graupel. The simulations results show that 80% rainfall is derived from warm cloud microphysical processes, and the rest is produced by cold cloud microphysical processes. The mixed phase microphysical process can invigorate the production of convective rainfall and enhance the liquid water content (LWC). In addition, the vertical distribution of LWC is mainly concentrated at the height isotherms of −10 to −20 °C in precipitation and the concentration area of LWC matches the distribution range of graupel particles. However, the growth of graupel particles depend on the microphysical processes of nucleation and propagation between rain and graupel particles (NUrg) and collision and coalescence between cloud droplets and graupel (CLcg), in which NUrg is a major source of graupel particles and the contribution of the process accounts for 77% of the amount of graupel particles.

Causes of variability in light absorption by particles in snow at sites in Idaho and Utah

AbstractA characterization of black carbon (BC) and other light‐absorbing particles in snow is presented for three mountain valley sites in Idaho in early 2014 and for one site near Vernal, Utah, in early 2013 and 2014. The focus of the study was on constraining the magnitude and drivers of variations in particulate absorbers in midlatitude U.S. seasonal snow. Mass mixing ratios of BC in newly fallen snow were similar at all three Idaho sites, with a median of 4.7 ± 4.2 ng BC per gram of snow. The median total light‐absorbing particulate mixing ratios in new snow, expressed as an equivalent mixing ratio of BC, was 18 ± 23 ng g−1. At the Utah site, which is near sources of both fossil fuel and dust, the mixing ratios of BC varied from 7 to 45 ng g−1 across seven new snowfall samples, and the BC‐equivalent mixing ratios varied from 9 to 1500 ng g−1. At all sites, dry deposition and in‐snow processes increase the mixing ratio of BC by up to an order of magnitude and increase the mixing ratio of all light‐absorbing particulates by up to 2 orders of magnitude, highlighting the importance of capturing these processes for accurately representing snow albedo in climate models. Spatial variability at a range of scales is found to be considerably smaller than the temporal variations at a given site, with implications for the representativeness of field samples used in observation/model comparisons.

Factors affecting the chemical composition of snowpack in the Kilpisjärvi area of North Scandinavia

Kilpisjärvi is a remote area in northwest Finland, almost without any local human impact on the environment. The design of the study was to investigate the chemical composition of local precipitation in the Kilpisjärvi region and determine the factors influencing it. To this aim, we collected 29 snow samples from the Lake Saana catchment and its surroundings in spring of 2008 and 2009. Already within the radius of a few hundred metres, significant chemical heterogeneity could be detected in the snow cover, caused by mixed marine and terrestrial precipitation and the impact of local rock dust. Based on the Cl−/Ca2+ ratio in snow, this could occur in localised areas, where marine or terrestrial aerosols predominate. Clear correlation was noted between SO42− and Ca2+, induced possibly by recombination of SO42− with carbonaceous dust. Other factors, such as nitrification in snow cover, could also have affected the pH levels of snow, which are mostly controlled by carbonate dust.

Effects of snow ratio on annual runoff within the Budyko framework

Abstract. A warmer climate may lead to less precipitation falling as snow in cold seasons. Such a switch in the state of precipitation not only alters temporal distribution of intra-annual runoff but also tends to yield less total annual runoff. Long-term water balance for 282 catchments across China is investigated, showing that a decreasing snow ratio reduces annual runoff for a given total precipitation. Within the Budyko framework, we develop an equation to quantify the relationship between snow ratio and annual runoff from a water–energy balance viewpoint. Based on the proposed equation, attribution of runoff change during the past several decades and possible runoff change induced by projected snow ratio change using climate experiment outputs archived in the Coupled Model Intercomparison Project Phase 5 (CMIP5) are analyzed. Results indicate that annual runoff in northwestern mountainous and northern high-latitude areas are sensitive to snow ratio change. The proposed model is applicable to other catchments easily and quantitatively for analyzing the effects of possible change in snow ratio on available water resources and evaluating the vulnerability of catchments to climate change.

Variações na composição isotópica de oxigênio na neve superficial ao longo de uma travessia antártica

Este trabalho apresenta a variabilidade das razões de isótopos de oxigênio na neve superficial ao longo de uma travessia do manto de gelo da Antártida ocidental realizada no verão austral de 2004/2005 por uma expedição conjunta entre pesquisadores chilenos e brasileiros. A travessia foi realizada entre a estação chilena Tenente Parodi, em Patriot Hills (80°18’S, 081°21’W) e o Polo Sul geográfico, cobrindo uma distância de mais de 1.205 km. Foram coletadas amostras de neve superficial (entre 0,05 a 0,2 m de profundidade) aproximadamente a cada 10 km (total de 104 amostras). A temperatura média anual foi obtida em seis pontos espaçados aproximadamente 220 km entre si, a uma profundidade entre 10 e 15 m. A razão isotópica do oxigênio (δ 18O) de cada amostra foi determinada por espectrometria de massas com fonte de gás (GSMS - Gas Source Mass Spectrometry) com precisão de 0,05 ‰. Os resultados indicam forte correlação entre δ 18O e temperatura local, latitude, altitude e distância da costa, sendo a primeira positiva e as outras negativas. Valores isotópicos relativamente altos são encontrados entre 87°30’S e 86°44’S, resultantes de processos pós-deposicionais devido à formação de glaze ice (esmalte de gelo) identificadas em campo. O gradiente δ18O/Elevação encontrado foi de -0,08‰ /100 m e o gradiente δ 18O/Temperatura de 0,743 ‰/°C. Com exceção das anomalias citadas, os resultados são concordantes com os encontrados por outros pesquisadores no manto de gelo antártico.

東南極表面雪のCa, Sr, Nd同位体比分析

東南極表面雪のCa, Sr, Nd同位体比分析

Black carbon and other light‐absorbing particles in snow of central North America

AbstractVertical profiles of light‐absorbing particles in seasonal snow were sampled from 67 North American sites. Over 500 snow samples and 55 soil samples from these sites were optically analyzed for spectrally resolved visible light absorption. The optical measurements were used to estimate black carbon (BC) mixing ratios in snow (), contributions to absorption by BC and non‐BC particles, and the absorption Ångström exponent of particles in snow and local soil. Sites in Canada tended to have the lowest BC mixing ratios (typically ~5–35 ng g−1), with somewhat higher in the Pacific Northwest (typically ~5–40 ng g−1) and Intramountain Northwest (typically 10–50 ng g−1). The Northern U.S. Plains sites were the dirtiest, with typically ~15–70 ng g−1 and multiple sample layers with >100 ng g−1 BC in snow. Snow water samples were also chemically analyzed for standard anions, selected carbohydrates, and various elements. The chemical and optical data were input to a Positive Matrix Factorization analysis of the sources of particulate light absorption. These were soil, biomass/biofuel burning, and fossil fuel pollution. Comparable analyses have been conducted for the Arctic and North China, providing a broad, internally consistent data set. As in North China, soil is a significant contributor to snow particulate light absorption in the Great Plains. We also examine the concentrations and sources of snow particulate light absorption across a latitudinal transect from the northern U.S. Great Plains to Arctic Canada by combining the current data with our earlier Arctic survey.