Measurement and simulation of the 16/17 April 2010 Eyjafjallajökull volcanic ash layer dispersion in the northern Alpine region

Atmospheric Chemistry and Physics (ACP), Vol. 11. N° 3. Emeis S.; Forkel R.; Junkermann W.; et al. - Copernicus GmbH, 2011

The spatial structure and the progression speed of the first ash layer from the Icelandic Eyjafjallajökull volcano which reached Germany on 16/17 April is investigated from remote sensing data and numerical simulations. The ceilometer network of the German Meteorological Service was able to follow the progression of the ash layer over the whole of Germany. This first ash layer turned out to be a rather shallow layer of only several hundreds of metres thickness which was oriented slantwise in the middle troposphere and which was brought downward by large-scale sinking motion over Southern Germa ...

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Measurement and simulation of the 16/17 April 2010 Eyjafjallajökull volcanic ash layer dispersion in the northern Alpine region

  Available online: http://dx.doi.org/10.5194/acp-11-2689-2011

S. Emeis ; R. Forkel ; W. Junkermann ; K. Schäfer ; H. Flentje ; S. Gilge ; W. Fricke ; M. Wiegner ; V. Freudenthaler ; S. Groβ ; L. Ries ; F. Meinhardt ; W. Birmili ; C. Münkel ; F. Obleitner ; P. Suppan

in Atmospheric Chemistry and Physics (ACP) > Vol. 11. N° 3 [03/01/2011] . - p.2689-2701

The spatial structure and the progression speed of the first ash layer from the Icelandic Eyjafjallajökull volcano which reached Germany on 16/17 April is investigated from remote sensing data and numerical simulations. The ceilometer network of the German Meteorological Service was able to follow the progression of the ash layer over the whole of Germany. This first ash layer turned out to be a rather shallow layer of only several hundreds of metres thickness which was oriented slantwise in the middle troposphere and which was brought downward by large-scale sinking motion over Southern Germany and the Alps. Special Raman lidar measurements, trajectory analyses and in-situ observations from mountain observatories helped to confirm the volcanic origin of the detected aerosol layer. Ultralight aircraft measurements permitted the detection of the arrival of a second major flush of volcanic material in Southern Germany. Numerical simulations with the Eulerian meso-scale model MCCM were able to reproduce the temporal and spatial structure of the ash layer. Comparisons of the model results with the ceilometer network data on 17 April and with the ultralight aircraft data on 19 April were satisfying. This is the first example of a model validation study from this ceilometer network data.

Language(s): English

Format: Digital (Free)

Tags: Alps, the ; Region VI - Europe ; Atmosphere ; Airborne ash ; Volcanic Eruption ; Natural hazards Add tag

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Distribution and air-sea exchange of mercury (Hg) in the Yellow Sea

Atmospheric Chemistry and Physics (ACP), Vol. 11. N° 3. Ci Z.J.; Zhang X.S.; Wang Z.W.; et al. - Copernicus GmbH, 2011

The Yellow Sea, surrounded by East China and the Korea Peninsula, is a potentially important receptor for anthropogenic mercury (Hg) emissions from East Asia. However, there is little documentation about the distribution and cycle of Hg in this marine system. During the cruise covering the Yellow Sea in July 2010, gaseous elemental mercury (GEM or Hg(0)) in the atmosphere, total Hg (THg), reactive Hg (RHg) and dissolved gaseous mercury (DGM, largely Hg(0)) in the waters were measured aboard the R/V Kexue III. The mean (±SD) concentration of GEM over the entire cruise was 2.61 ± 0.50 ng m−3 (ra ...

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Distribution and air-sea exchange of mercury (Hg) in the Yellow Sea

  Available online: http://dx.doi.org/10.5194/acp-11-2881-2011

Z.J. Ci ; X.S. Zhang ; Z.W. Wang ; Z.C. Niu ; X.Y. Diao ; S.W. Wang

in Atmospheric Chemistry and Physics (ACP) > Vol. 11. N° 3 [03/01/2011] . - p.2881-2892

The Yellow Sea, surrounded by East China and the Korea Peninsula, is a potentially important receptor for anthropogenic mercury (Hg) emissions from East Asia. However, there is little documentation about the distribution and cycle of Hg in this marine system. During the cruise covering the Yellow Sea in July 2010, gaseous elemental mercury (GEM or Hg(0)) in the atmosphere, total Hg (THg), reactive Hg (RHg) and dissolved gaseous mercury (DGM, largely Hg(0)) in the waters were measured aboard the R/V Kexue III. The mean (±SD) concentration of GEM over the entire cruise was 2.61 ± 0.50 ng m−3 (range: 1.68 to 4.34 ng m−3), which were generally higher than other open oceans. The spatial distribution of GEM generally reflected a clear gradient with high levels near the coast of East China and low levels in open waters, suggesting the significant atmospheric Hg outflow from East China. The mean concentration of THg in the surface waters was 1.69 ± 0.35 ng l−1 and the RHg accounted for a considerable fraction of THg (RHg: 1.08 ± 0.28 ng l−1, %RHg/THg = 63.9%). The mean concentration of DGM in the surface waters was 63.9 ± 13.7 pg l−1 and always suggested the supersaturation of Hg(0) in the surface waters with respect to Hg(0) in the atmosphere (the degree of saturation: 7.8 ± 2.3 with a range of 3.6–14.0). The mean Hg(0) flux at the air-sea interface was estimated to be 18.3 ± 11.8 ng m−2 h−1 based on a two-layer exchange model. The high wind speed and DGM levels induced the extremely high Hg(0) emission rates. Measurements at three stations showed no clear vertical patterns of DGM, RHg and THg in the water column. Overall, the elevated Hg levels in the Yellow Sea compared with other open oceans suggested that the human activity has influenced the oceanic Hg cycle downwind of East Asia.

Language(s): English

Format: Digital (Free)

Tags: Region II - Asia ; China ; Republic of Korea ; Yellow Sea ; Atmosphere ; Ocean-atmosphere interaction ; Metals ; Observations ; Air pollution Add tag

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Chemical composition and mixing-state of ice residuals sampled within mixed phase clouds

Atmospheric Chemistry and Physics (ACP), Vol. 11. N° 3. Ebert M.; Worringen A.; Benker N.; et al. - Copernicus GmbH, 2011

During an intensive campaign at the high alpine research station Jungfraujoch, Switzerland, in February/March 2006 ice particle residuals within mixed-phase clouds were sampled using the Ice-counterflow virtual impactor (Ice-CVI). Size, morphology, chemical composition, mineralogy and mixing state of the ice residual and the interstitial (i.e., non-activated) aerosol particles were analyzed by scanning and transmission electron microscopy. Ice nuclei (IN) were identified from the significant enrichment of particle groups in the ice residual (IR) samples relative to the interstitial aerosol. In ...

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Chemical composition and mixing-state of ice residuals sampled within mixed phase clouds

  Available online: http://dx.doi.org/10.5194/acp-11-2805-2011

M. Ebert ; A. Worringen ; N. Benker ; S. Mertes ; E. Weingartner ; S. Weinbruch

in Atmospheric Chemistry and Physics (ACP) > Vol. 11. N° 3 [03/01/2011] . - p.2805-2816

During an intensive campaign at the high alpine research station Jungfraujoch, Switzerland, in February/March 2006 ice particle residuals within mixed-phase clouds were sampled using the Ice-counterflow virtual impactor (Ice-CVI). Size, morphology, chemical composition, mineralogy and mixing state of the ice residual and the interstitial (i.e., non-activated) aerosol particles were analyzed by scanning and transmission electron microscopy. Ice nuclei (IN) were identified from the significant enrichment of particle groups in the ice residual (IR) samples relative to the interstitial aerosol. In terms of number lead-bearing particles are enriched by a factor of approximately 25, complex internal mixtures with silicates or metal oxides as major components by a factor of 11, and mixtures of secondary aerosol and carbonaceous material (C-O-S particles) by a factor of 2. Other particle groups (sulfates, sea salt, Ca-rich particles, external silicates) observed in the ice-residual samples cannot be assigned unambiguously as IN. Between 9 and 24% of all IR are Pb-bearing particles. Pb was found as major component in around 10% of these particles (PbO, PbCl2). In the other particles, Pb was found as some 100 nm sized agglomerates consisting of 3–8 nm sized primary particles (PbS, elemental Pb). C-O-S particles are present in the IR at an abundance of 17–27%. The soot component within these particles is strongly aged. Complex internal mixtures occur in the IR at an abundance of 9–15%. Most IN identified at the Jungfraujoch station are internal mixtures containing anthropogenic components (either as main or minor constituent), and it is concluded that admixture of the anthropogenic component is responsible for the increased IN efficiency within mixed phase clouds. The mixing state appears to be a key parameter for the ice nucleation behaviour that cannot be predicted from the sole knowledge of the main component of an individual particle.

Language(s): English

Format: Digital (Free)

Tags: Aerosols ; Atmosphere ; Glaciology ; Cloud ; Observations ; Air pollution ; Alps, the ; Region VI - Europe Add tag

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Origin and radiative forcing of black carbon transported to the Himalayas and Tibetan Plateau

Atmospheric Chemistry and Physics (ACP), Vol. 11. N° 3. Kopacz M.; Mauzerall D.L.; Wang J.; et al. - Copernicus GmbH, 2011

The remote and high elevation regions of central Asia are influenced by black carbon (BC) emissions from a variety of locations. BC deposition contributes to melting of glaciers and questions exist, of both scientific and policy interest, as to the origin of the BC reaching the glaciers. We use the adjoint of the GEOS-Chem model to identify the location from which BC arriving at a variety of locations in the Himalayas and Tibetan Plateau originates. We then calculate its direct and snow-albedo radiative forcing. We analyze the seasonal variation in the origin of BC using an adjoint sensitivity ...

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Origin and radiative forcing of black carbon transported to the Himalayas and Tibetan Plateau

  Available online: http://dx.doi.org/10.5194/acp-11-2837-2011

M. Kopacz ; D.L. Mauzerall ; J. Wang ; E.M. Leibensperger ; D.K. Henze ; K. Singh

in Atmospheric Chemistry and Physics (ACP) > Vol. 11. N° 3 [03/01/2011] . - p.2837-2852

The remote and high elevation regions of central Asia are influenced by black carbon (BC) emissions from a variety of locations. BC deposition contributes to melting of glaciers and questions exist, of both scientific and policy interest, as to the origin of the BC reaching the glaciers. We use the adjoint of the GEOS-Chem model to identify the location from which BC arriving at a variety of locations in the Himalayas and Tibetan Plateau originates. We then calculate its direct and snow-albedo radiative forcing. We analyze the seasonal variation in the origin of BC using an adjoint sensitivity analysis, which provides a detailed map of the location of emissions that directly contribute to black carbon concentrations at receptor locations. We find that emissions from northern India and central China contribute the majority of BC to the Himalayas, although the precise location varies with season. The Tibetan Plateau receives most BC from western and central China, as well as from India, Nepal, the Middle East, Pakistan and other countries. The magnitude of contribution from each region varies with season and receptor location. We find that sources as varied as African biomass burning and Middle Eastern fossil fuel combustion can significantly contribute to the BC reaching the Himalayas and Tibetan Plateau. We compute radiative forcing in the snow-covered regions and find the forcing due to the BC induced snow-albedo effect to vary from 5–15 W m−2 within the region, an order of magnitude larger than radiative forcing due to the direct effect, and with significant seasonal variation in the northern Tibetan Plateau. Radiative forcing from reduced snow albedo likely accelerates glacier melting. Our analysis may help inform mitigation efforts to slow the rate of glacial melt by identifying regions that make the largest contributions to BC deposition in the Himalayas and Tibetan Plateau.

Language(s): English

Format: Digital (Free)

Tags: Atmosphere ; Atmospheric circulation ; Air pollution ; China ; Himalayas ; Tibet, China Add tag

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Origin and radiative forcing of black carbon transported to the Himalayas and Tibetan Plateau

Atmospheric Chemistry and Physics (ACP), Vol. 11. N° 3. Kopacz M.; Mauzerall D.L.; Wang J.; et al. - Copernicus GmbH, 2011

The remote and high elevation regions of central Asia are influenced by black carbon (BC) emissions from a variety of locations. BC deposition contributes to melting of glaciers and questions exist, of both scientific and policy interest, as to the origin of the BC reaching the glaciers. We use the adjoint of the GEOS-Chem model to identify the location from which BC arriving at a variety of locations in the Himalayas and Tibetan Plateau originates. We then calculate its direct and snow-albedo radiative forcing. We analyze the seasonal variation in the origin of BC using an adjoint sensitivity ...

English

[article] 

Origin and radiative forcing of black carbon transported to the Himalayas and Tibetan Plateau

  Available online: http://dx.doi.org/10.5194/acp-11-2837-2011

M. Kopacz ; D.L. Mauzerall ; J. Wang ; E.M. Leibensperger ; D.K. Henze ; K. Singh

in Atmospheric Chemistry and Physics (ACP) > Vol. 11. N° 3 [03/01/2011] . - p.2837-2852

The remote and high elevation regions of central Asia are influenced by black carbon (BC) emissions from a variety of locations. BC deposition contributes to melting of glaciers and questions exist, of both scientific and policy interest, as to the origin of the BC reaching the glaciers. We use the adjoint of the GEOS-Chem model to identify the location from which BC arriving at a variety of locations in the Himalayas and Tibetan Plateau originates. We then calculate its direct and snow-albedo radiative forcing. We analyze the seasonal variation in the origin of BC using an adjoint sensitivity analysis, which provides a detailed map of the location of emissions that directly contribute to black carbon concentrations at receptor locations. We find that emissions from northern India and central China contribute the majority of BC to the Himalayas, although the precise location varies with season. The Tibetan Plateau receives most BC from western and central China, as well as from India, Nepal, the Middle East, Pakistan and other countries. The magnitude of contribution from each region varies with season and receptor location. We find that sources as varied as African biomass burning and Middle Eastern fossil fuel combustion can significantly contribute to the BC reaching the Himalayas and Tibetan Plateau. We compute radiative forcing in the snow-covered regions and find the forcing due to the BC induced snow-albedo effect to vary from 5–15 W m−2 within the region, an order of magnitude larger than radiative forcing due to the direct effect, and with significant seasonal variation in the northern Tibetan Plateau. Radiative forcing from reduced snow albedo likely accelerates glacier melting. Our analysis may help inform mitigation efforts to slow the rate of glacial melt by identifying regions that make the largest contributions to BC deposition in the Himalayas and Tibetan Plateau.

Language(s): English

Format: Digital (Free)

Tags: Atmosphere ; Atmospheric circulation ; Air pollution ; China ; Himalayas ; Tibet, China Add tag

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Changes in the potential distribution of humid tropical forests on a warmer planet

Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 369. N° 1934. Zelazowski Przemyslaw; Malhi Yadvinder; Huntingford Chris; et al. - The Royal Society, 2011

The future of tropical forests has become one of the iconic issues in climate-change science. A number of studies that have explored this subject have tended to focus on the output from one or a few climate models, which work at low spatial resolution, whereas society and conservation-relevant assessment of potential impacts requires a finer scale. This study focuses on the role of climate on the current and future distribution of humid tropical forests (HTFs). We first characterize their contemporary climatological niche using annual rainfall and maximum climatological water stress, which als ...

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The perfect storm

Global Change magazine, Issue 76. IGBP, 2011

English

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Vol. 27 No.2 - 2010

is an issue of Geofizika. Andrija Mohorovičić Geophysical Institute,, 2011

7. Janeković, I., Sikirić, M. D., Tomažić, I. and Kuzmić, M. (2010): Hindcasting the Adriatic Sea surface temperature and salinity: A recent modeling experience. Geofizika, 27, 85-100.

8. Anil Kumar, R., Dudhia, J. and Roy Bhowmik, S. K. (2010): Evaluation of physics options of the Weather Research and Forecasting (WRF) Model to simulate high impact heavy rainfall events over Indian Monsoon region. Geofizika, 27, 101-125.

9. Jurčec, V. and Dragojlović, D. (2010): The unexpected snowstorm of 13 - 14 January 2002 in Zagreb. Geofizika, 27, 127-145.

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52 (4) - 2010

is an issue of Oceanologia. IO-PAN, 2011

Contains:

Invited papers

* Solar radiation in the Baltic Sea: Jerzy Dera, Bogdan Woźniak


Papers

* Solar radiation at the surface in the Baltic Proper: Sirje Keevallik, Kai Loitjärv

* Variability in aerosol optical properties at Hornsund, Spitsbergen: Anna Rozwadowska, Piotr Sobolewski

* Particulate organic carbon in the southern Baltic Sea: numerical simulations and experimental data: Lidia Dzierzbicka-Głowacka, Karol Kuliński, Anna Maciejewska, Jaromir Jakacki, Janusz Pempkowiak

English

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WOCE Atlas volume 2 - Pacific Ocean

World Meteorological Organization (WMO) ; Bundesamt für Seeschifffahrt und Hydrographie (BSH) - BSH, 2011

English

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WOCE Atlas volume 4 - Indian Ocean : hydrographic atlas

World Meteorological Organization (WMO) ; US National Science Foundation ; BP , 2011

The Hydrographic Programme of the international World Ocean Circulation Experiment (WOCE) was a comprehensive global hydrographic survey of physical and chemical properties, of unprecedented scope and quality, and represents the "state of the oceans" during the 1990s.

The "Printed Atlas" is a copy of the published volume and contains full introductory text. The "Digital Atlas" presents the same graphical material, with additional properties and levels, ancillary data sets, and bibliographic material for each of the vertical sections.

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WOCE Atlas volume 3 - Atlantic Ocean : hydrographic atlas

World Meteorological Organization (WMO) ; Bundesamt für Seeschifffahrt und Hydrographie (BSH) - BSH, 2011

The Hydrographic Programme of the World Ocean Circulation Experiment (WOCE) was a comprehensive global hydrographic survey of physical and chemical properties, of unprecedented scope and quality, and represents the "state of the oceans" during the 1990s.

The "Printed Atlas" is a copy of the published volume and contains full introductory text. The "Digital Atlas" presents the same graphical material, with additional properties and levels, ancillary data sets, and bibliographic material for each of the vertical sections.

English

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Terre, eau, et forêts: ressorts d’un développement à l’épreuve du changement climatique en Afrique

FEM, 2011

French, English

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IOC Manuals and Guides, 57. Reducing and managing the risk of tsunamis

UNESCO, 2011

English

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Land, Water, and Forests: Assets for Climate resilient Development in Africa

GEF, 2011

One third of all African people live today in drought-prone areas, and 250 million are exposed to drought every year. "Land, Water, and Forests" is a publication that covers the topics of land degradation, deforestation, desertification and water scarcity in the cases of the Congo Basin, Lake Chad and the Sahel region.

English, French

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