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Liu, J, Dedrick J, Russell LM, Senum GI, Uin J, Kuang CG, Springston SR, Leaitch WR, Aiken AC, Lubin D.  2018.  High summertime aerosol organic functional group concentrations from marine and seabird sources at Ross Island, Antarctica, during AWARE. Atmospheric Chemistry and Physics. 18:8571-8587.   10.5194/acp-18-8571-2018   AbstractWebsite

Observations of the organic components of the natural aerosol are scarce in Antarctica, which limits our understanding of natural aerosols and their connection to seasonal and spatial patterns of cloud albedo in the region. From November 2015 to December 2016, the ARM West Antarctic Radiation Experiment (AWARE) measured submicron aerosol properties near McMurdo Station at the southern tip of Ross Island. Submicron organic mass (OM), particle number, and cloud condensation nuclei concentrations were higher in summer than other seasons. The measurements included a range of compositions and concentrations that likely reflected both local anthropogenic emissions and natural background sources. We isolated the natural organic components by separating a natural factor and a local combustion factor. The natural OM was 150 times higher in summer than in winter. The local anthropogenic emissions were not hygroscopic and had little contribution to the CCN concentrations. Natural sources that included marine sea spray and seabird emissions contributed 56 % OM in summer but only 3 % in winter. The natural OM had high hydroxyl group fraction (55 %), 6 % alkane, and 6 % amine group mass, consistent with marine organic composition. In addition, the Fourier transform infrared (FTIR) spectra showed the natural sources of organic aerosol were characterized by amide group absorption, which may be from seabird populations. Carboxylic acid group contributions were high in summer and associated with natural sources, likely forming by secondary reactions.

Smith, WL, Hansen C, Bucholtz A, Anderson BE, Beckley M, Corbett JG, Cullather RI, Hines KM, Hofton M, Kato S, Lubin D, Moore RH, Rosenhaimer MS, Redemann J, Schmidt S, Scott R, Song S, Barrick JD, Blair JB, Bromwich DH, Brooks C, Chen G, Cornejo H, Corr CA, Ham SH, Kittelman AS, Knappmiller S, LeBlanc S, Loeb NG, Miller C, Nguyen L, Palikonda R, Rabine D, Reid EA, Richter-Menge JA, Pilewswskie P, Shinozuka Y, Spangenberg D, Stackhouse P, Taylor P, Thornhill KL, Van Gilst D, Winstead E.  2017.  ARCTIC RADIATION-ICEBRIDGE SEA AND ICE EXPERIMENT The Arctic Radiant Energy System during the Critical Seasonal Ice Transition. Bulletin of the American Meteorological Society. 98:1399-1426.   10.1175/bams-d-14-00277.1   AbstractWebsite

Through ARISE, NASA acquired unique aircraft data on clouds, atmospheric radiation and sea ice properties during the critical period between the sea ice minimum in late summer and autumn and the commencement of refreezing.

Markus, T, Neumann T, Martino A, Abdalati W, Brunt K, Csatho B, Farrell S, Fricker H, Gardner A, Harding D, Jasinski M, Kwok R, Magruder L, Lubin D, Luthcke S, Morison J, Nelson R, Neuenschwander A, Palm S, Popescu S, Shum CK, Schutz BE, Smith B, Yang YK, Zwally J.  2017.  The Ice, Cloud, and land Elevation Satellite-2 (ICESat-2): Science requirements, concept, and implementation. Remote Sensing of Environment. 190:260-273.   10.1016/j.rse.2016.12.029   AbstractWebsite

The Ice, Cloud, and land Elevation Satellite (ICESat) mission used laser altimetry measurements to determine changes in elevations of glaciers and ice sheets, as well as sea ice thickness distribution. These measurements have provided important information on the response of the cryopshere (Earth's frozen surfaces) to changes in atmosphere and ocean condition. ICESat operated from 2003 to 2009 and provided repeat altimetry measurements not only to the cryosphere scientific community but also to the ocean, terrestrial and atmospheric scientific communities. The conclusive assessment of significant ongoing rapid changes in the Earth's ice cover, in part supported by ICESat observations, has strengthened the need for sustained, high accuracy, repeat observations similar to what was provided by the ICESat mission. Following recommendations from the National Research Council for an ICESat follow-on mission, the ICESat-2 mission is now under development for planned launch in 2018. The primary scientific aims of the ICESat-2 mission are to continue measurements of sea ice freeboard and ice sheet elevation to determine their changes at scales from outlet glaciers to the entire ice sheet, and from 105 of meters to the entire polar oceans for sea ice freeboard. ICESat carried a single beam profiling laser altimeter that produced similar to 70 m diameter footprints on the surface of the Earth at similar to 150 m along-track intervals. In contrast, ICESat-2 will operate with three pairs of beams, each pair separated by about 3 km cross-track with a pair spacing of 90 m. Each of the beams will have a nominal 17 m diameter footprint with an along -track sampling interval of 0.7 m. The differences in the ICESat-2 measurement concept are a result of overcoming some limitations associated with the approach used in the ICESat mission. The beam pair configuration of ICESat-2 allows for the determination of local cross -track slope, a significant factor in measuring elevation change for the outlet glaciers surrounding the Greenland and Antarctica coasts. The multiple beam pairs also provide improved spatial coverage. The dense spatial sampling eliminates along -track measurement gaps, and the small footprint diameter is especially useful for sea surface height measurements in the often narrow leads needed for sea ice freeboard and ice thickness retrievals. The ICESat-2 instrumentation concept uses a low energy 532 nm (green) laser in conjunction with single-photon sensitive detectors to measure range. Combining ICESat-2 data with altimetry data collected since the start of the ICESat mission in 2003, such as Operation IceBridge and ESA's CryoSat-2, will yield a 15+ year record of changes in ice sheet elevation and sea ice thickness. ICESat-2 will also provide information of mountain glacier and ice cap elevations changes, land and vegetation heights, inland water elevations, sea surface heights, and cloud layering and optical thickness. Published by Elsevier Inc. This is an open access article under the CC BY license

Lubin, D, Ayres G, Hart S.  2009.  REMOTE SENSING OF POLAR REGIONS Lessons and Resources for the International Polar Year. Bulletin of the American Meteorological Society. 90:825-+.   10.1175/2008bams2596.1   AbstractWebsite

Polar researchers have historically been innovative and adaptive users of satellite remote sensing data, and their experiences can suggest ways to enhance the use of remote sensing throughout the climate sciences. We performed a semistructured survey of the polar research community on the use of remote sensing at the beginning of the NASA Earth Observing System (EOS) era. For the most part, remote sensing plays a supporting but critical role in the research as described by the respondents. Data acquisition and analysis is mostly at the home institution, with field telemetry appearing in a small minority of responses. Most polar researchers have not had formal training in remote sensing, but they have adapted and trained themselves very thoroughly. Although a significant number of polar researchers are content with visual inspection of satellite images, a roughly equal number develop their own algorithms for derivation of geophysical products, and more have become adept at using high-level graphical programming languages to work with data. Given the self-sufficiency in remote sensing training that characterizes polar researchers, nontraditional satellite data users (e.g., life scientists) tend to view the "learning curve" as steep, as compared with physical scientists. Although up to a third of respondents report no significant obstacles in accessing satellite data, obstacles such as a) difficulty locating data centers for their needs, b) the cost of acquiring data, and c) insider or restricted access to data were each reported by about one-quarter of the respondents. The major ongoing challenges with remote sensing in polar research can be met with aspects of modern cyberinfrastructure involving data interoperability.

Bais, AF, Lubin D, Arola A, Bernhard G, Blumthaler M, Chubarova N, Erlick C, Gies HP, Krotkov NA, Lantz K, Mayer B, Mckenzie RL, d. Piacentini R, Seckmeyer G, Slusser JR, Zerefos CZ.  2007.  Surface Ultraviolet Radiation: Past, Present, and Future. Scientific assessment of ozone depletion: 2006. ( Organization W, Ed.)., Geneva, Switzerland: World Meteorological Organization Abstract
Lubin, D, Arrigo KR, van Dijken GL.  2004.  Increased exposure of Southern Ocean phytoplankton to ultraviolet radiation. Geophysical Research Letters. 31   10.1029/2004gl019633   AbstractWebsite

Satellite remote sensing of both surface solar ultraviolet radiation (UVR) and chlorophyll over two decades shows that biologically significant ultraviolet radiation increases began to occur over the Southern Ocean three years before the ozone "hole'' was discovered. Beginning in October 1983, the most frequent occurrences of enhanced UVR over phytoplankton-rich waters occurred in the Weddell Sea and Indian Ocean sectors of the Southern Ocean, impacting 60% of the surface biomass by the late 1990s. These results suggest two reasons why more serious impacts to the base of the marine food web may not have been detected by field experiments: ( 1) the onset of UVR increases several years before dedicated field work began may have impacted the most sensitive organisms long before such damage could be detected, and ( 2) most biological field work has so far not taken place in Antarctic waters most extensively subjected to enhanced UVR.

Arrigo, KR, Lubin D, van Dijken GL, Holm-Hansen O, Morrow E.  2003.  Impact of a deep ozone hole on Southern Ocean primary production. Journal of Geophysical Research-Oceans. 108   10.1029/2001jc001226   AbstractWebsite

[1] Field studies show that photosynthesis by Antarctic phytoplankton is inhibited by the increased ultraviolet radiation (UVR) resulting from springtime stratospheric ozone (O-3) depletion. To extend previous observations, a numerical model utilizing satellite-derived distributions of O-3, clouds, sea ice, surface temperature, and phytoplankton biomass was developed to study the hemispheric-scale seasonal effects of a deep Antarctic O-3 hole on primary production in the Southern Ocean. UVR-induced losses of surface phytoplankton production were substantial under all O-3 conditions, mostly due to UVA. However, when integrated to the 0.1% light depth, the loss of primary production resulting from enhanced fluxes of UVB due to O-3 depletion was <0.25%. The loss of primary production is minimized by the strong attenuation of UVR within the water column and by sea ice which is at its peak extent at the time of the most severe O-3 depletion.

Ramanathan, V, Crutzen PJ, Lelieveld J, Mitra AP, Althausen D, Anderson J, Andreae MO, Cantrell W, Cass GR, Chung CE, Clarke AD, Coakley JA, Collins WD, Conant WC, Dulac F, Heintzenberg J, Heymsfield AJ, Holben B, Howell S, Hudson J, Jayaraman A, Kiehl JT, Krishnamurti TN, Lubin D, McFarquhar G, Novakov T, Ogren JA, Podgorny IA, Prather K, Priestley K, Prospero JM, Quinn PK, Rajeev K, Rasch P, Rupert S, Sadourny R, Satheesh SK, Shaw GE, Sheridan P, Valero FPJ.  2001.  Indian Ocean Experiment: An integrated analysis of the climate forcing and effects of the great Indo-Asian haze. Journal of Geophysical Research-Atmospheres. 106:28371-28398.   10.1029/2001jd900133   AbstractWebsite

Every year, from December to April, anthropogenic haze spreads over most of the North Indian Ocean, and South and Southeast Asia. The Indian Ocean Experiment (INDOEX) documented this Indo-Asian haze at scales ranging from individual particles to its contribution to the regional climate forcing. This study integrates the multiplatform. observations (satellites, aircraft, ships, surface stations, and balloons) with one- and four-dimensional models to derive the regional aerosol forcing resulting from the direct, the semidirect and the two indirect effects. The haze particles consisted of several inorganic and carbonaceous species, including absorbing black carbon clusters, fly ash, and mineral dust. The most striking result was the large loading of aerosols over most of the South Asian region and the North Indian Ocean. The January to March 1999 visible optical depths were about 0.5 over most of the continent and reached values as large as 0.2 over the equatorial Indian ocean due to long-range transport. The aerosol layer extended as high as 3 km. Black carbon contributed about 14% to the fine particle mass and 11% to the visible optical depth. The single-scattering albedo estimated by several independent methods was consistently around 0.9 both inland and over the open ocean. Anthropogenic sources contributed as much as 80% (+/- 10%) to the aerosol loading and the optical depth. The in situ data, which clearly support the existence of the first indirect effect (increased aerosol concentration producing more cloud drops with smaller effective radii), are used to develop a composite indirect effect scheme. The Indo-Asian aerosols impact the radiative forcing through a complex set of heating (positive forcing) and cooling (negative forcing) processes. Clouds and black carbon emerge as the ma or players. The dominant factor, however, is the large negative forcing (-20 +/- 4 W m(-2)) at the surface and the comparably large atmospheric heating. Regionally, the absorbing haze decreased the surface solar radiation by an amount comparable to 50% of the total ocean heat flux and nearly doubled the lower tropospheric solar heating. We demonstrate with a general circulation model how this additional heating significantly perturbs the tropical rainfall patterns and the hydrological cycle with implications to global climate.

Aagaard, K, Barrie L, Carmack E, Garrity C, Jones EP, Lubin D, Macdonald RW, Swift JH, Tucker W, Wheeler PA, Whritner R.  1996.  U.S., Canadian researchers explore Arctic Ocean. EOS, Transactions American Geophysical Union. 77:209,213.   10.1029/96EO00141   Abstract

During July–September 1994, two Canadian and U.S. ice breakers crossed the Arctic Ocean (Figure 1) to investigate the biological, chemical, and physical systems that define the role of the Arctic in global change. The results are changing our perceptions of the Arctic Ocean as a static environment with low biological productivity to a dynamic and productive system. The experiment was called the Arctic Ocean Section (AOS) and the ships were the Canadian Coast Guard ship Louis S. St.-Laurent and the U.S. Coast Guard cutter Polar Sea.

Lubin, D, Mitchell BG, Frederick JE, Alberts AD, Booth CR, Lucas T, Neuschuler D.  1992.  A Contribution toward Understanding the Biospherical Significance of Antarctic Ozone Depletion. Journal of Geophysical Research-Atmospheres. 97:7817-7828.   10.1029/91JD01400   AbstractWebsite

Measurements of biologically active UV radiation made by the National Science Foundation (NSF) scanning spectroradiometer (UV-monitor) at Palmer Station. Antarctica, during the Austral springs of 1988, 1989, and 1990 are presented and compared. Column ozone abundance above Palmer Station is computed from these measurements using a multiple wavelength algorithm. Two contrasting action spectra (biological weighting functions) are used to estimate the biologically relevant (dose from the spectral measurements: a standard weighting function for damage to DNA, and a new action spectrum representing the potential for photosynthesis inhibition in Antarctic phytoplankton. The former weights only UV-B wavelengths (280-320 nm) and gives the most weight to wavelengths shorter than 300 nm, while the latter includes large contributions out to 355 nm. The latter is the result of recent Antarctic field work and is relevant in that phytoplankton constitute the base of the Antarctic food web. The modest ozone hole of 1988, in which the ozone abundance above Palmer Station never fell below 200 Dobson units (DU), brought about summerlike doses of DNA-effective UV radiation 2 months early, but UV doses which could inhibit photosynthesis in phytoplankton did not exceed a clear-sky "maximum normal" dose for that time of year. The severe ozone holes of 1989 and 1990, in which the ozone abundance regularly fell below 200 DU, brought about increases in UV surface irradiance weighted by either action spectrum. Ozone abundances and dose-weighted irradiances provided by the NSF UV-monitor are used to derive the radiation amplification factors (RAFs) for both DNA-effective irradiance and phytoplankton-effective irradiance. The RAF for DNA-effective irradiance is nonlinear in ozone abundance and is in excess of the popular "two for one" rule, while the RAF for phytoplankton-effective irradiance approximately follows a "one for one" rule.