Black carbon record based on a shallow Himalayan ice core and its climatic implications

Abstract. A continuous measurement for black carbon (hereafter "BC") in a 40 m shallow ice core retrieved from the East Rongbuk Glacier (hereafter "ERG") in the northeast saddle of Mt. Qomolangma (Everest) provided the first historical record of BC deposition during the past ~50 yrs in the high Himalyas. Apparent increasing trend (smooth average) of BC concentrations was revealed since the mid-1990s. Seasonal variability of BC concentrations in the ice core indicated higher concentrations in monsoon seasons than those in non-monsoon seasons. Backward air trajectory analysis by the HYSPLIT model indicated that South Asia's BC emissions had significant impacts on the BC deposition in the Mt. Qomolangma (Everest) region. The estimated average atmospheric BC concentration in the region was about 80 ng m−3 during 1951–2001. And it was suggested BC emitted from South Asia could penetrate into the Tibetan Plateau by climbing over the elevated Himalayas. A significant increasing trend of the radiative forcing simulated by the SNICAR model appeared since 1990, which even exceeded 4.5 W m−2 in the summer of 2001. It was suggested that this amplitudes of BC concentrations in the atmosphere over the Himalayas and consequently in the ice in the glaciers could not be neglected when assessing the dual warming effects on glacier melting in the Himalayas.

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History of desert dust deposition recorded in the Elbrus ice core

10.5194/acp-2019-411 ◽

2019 ◽

Author(s):

Stanislav Kutuzov ◽

Michel Legrand ◽

Suzanne Preunkert ◽

Patrick Ginot ◽

Vladimir Mikhalenko ◽

...

Keyword(s):

North Africa ◽

Drought Index ◽

Decadal Variability ◽

Ice Core ◽

Ice Cores ◽

Dust Deposition ◽

The Past ◽

Dust Sources ◽

Increasing Trend ◽

History Of

Abstract. Ice cores are one of the most valuable paleo-archives. Records from the ice cores can provide information not only about the amount of dust in the atmosphere but also about dust sources and its changes in the past. A 182 m long ice core has been recovered at the western plateau of Mt. Elbrus (5115 m elevation) in 2009. This record was extended with the shallow ice core drilling in 2013. Here we present analysis of the concentrations of Ca2+, a commonly used proxy of dust, recorded in Elbrus ice core over the period 1774–2013. The calcium record reveals a quasi decadal variability with a general increasing trend. Using multiple regression analysis we found a statistically significant spatial correlation of the Elbrus Ca2+ summer concentrations and precipitation and soil moisture content in Levant region (specifically Syria and Iraq). The Ca2+ record also correlates with drought index in North Africa (r = 0.69 p

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Temperature variations over the past millennium on the Tibetan Plateau revealed by four ice cores

Annals of Glaciology ◽

10.3189/172756407782871305 ◽

2007 ◽

Vol 46 ◽

pp. 362-366 ◽

Cited By ~ 14

Author(s):

Tandong Yao ◽

Keqin Duan ◽

L.G. Thompson ◽

Ninglian Wang ◽

Lide Tian ◽

...

Keyword(s):

Tibetan Plateau ◽

19Th Century ◽

Northern Hemisphere ◽

Ice Core ◽

Ice Cores ◽

Ice Age ◽

The Tibetan Plateau ◽

Late 19Th Century ◽

The Past ◽

Northern Tibetan Plateau

AbstractTemperature variation on the Tibetan Plateau over the last 1000 years has been inferred using a composite δ18O record from four ice cores. Data from a new ice core recovered from the Puruogangri ice field in the central Tibetan Plateau are combined with those from three other cores (Dunde, Guliya and Dasuopu) recovered previously. The ice-core δ18O composite record indicates that the temperature change on the whole Tibetan Plateau is similar to that in the Northern Hemisphere on multi-decadal timescales except that there is no decreasing trend from AD 1000 to the late 19th century. The δ18O composite record from the northern Tibetan Plateau, however, indicates a cooling trend from AD 1000 to the late 19th century, which is more consistent with the Northern Hemisphere temperature reconstruction. The δ18O composite record reveals the existence of the Medieval Warm Period and the Little Ice Age (LIA) on the Tibetan Plateau. However, on the Tibetan Plateau the LIA is not the coldest period during the last millennium as in other regions in the Northern Hemisphere. The present study indicates that the 20th-century warming on the Tibetan Plateau is abrupt, and is warmer than at any time during the past 1000 years.

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Integration of Tibetan Plateau ice-core temperature records and the influence of atmospheric circulation on isotopic signals in the past century

Quaternary Research ◽

10.1016/j.yqres.2014.01.006 ◽

2014 ◽

Vol 81 (3) ◽

pp. 520-530 ◽

Cited By ~ 9

Author(s):

Xiaoxin Yang ◽

Tandong Yao ◽

Daniel Joswiak ◽

Ping Yao

Keyword(s):

Tibetan Plateau ◽

Atmospheric Circulation ◽

El Niño ◽

El Nino ◽

Southern Oscillation ◽

Ice Core ◽

Past Century ◽

The Tibetan Plateau ◽

The Past ◽

Increasing Trends

AbstractTemperature signals in ice-core δ18O on the Tibetan Plateau (TP), particularly in the central and southern parts, continue to be debated because of the large scale of atmospheric circulation. This study presents ten ice-core δ18O records at an annual resolution, with four (Malan, Muztagata, Guliya, and Dunde) in the northern, three (Puruogangri, Geladaindong, Tanggula) in the central and three (Noijin Kangsang, Dasuopu, East Rongbuk) in the southern TP. Integration shows commonly increasing trends in δ18O in the past century, featuring the largest one in the northern, a moderate one in the central and the smallest one in the southern TP, which are all consistent with ground-based measurements of temperature. The influence of atmospheric circulation on isotopic signals in the past century was discussed through the analysis of El Niño/Southern Oscillation (ENSO), and of possible connections between sea surface temperature (SST) and the different increasing trends in both ice-core δ18O and temperature. Particularly, El Niño and the corresponding warm Bay of Bengal (BOB) SST enhance the TP ice-core isotopic enrichment, while La Niña, or corresponding cold BOB SST, causes depletion. This thus suggests a potential for reconstructing the ENSO history from the TP ice-core δ18O.

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Trends and features of climatic changes in the past 5000 years recorded by the Dunde ice core

Annals of Glaciology ◽

10.3189/1992aog16-1-21-24 ◽

1992 ◽

Vol 16 ◽

pp. 21-24 ◽

Cited By ~ 19

Author(s):

Yao Tandong ◽

L. G. Thompson

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Climatic Changes ◽

Ice Age ◽

The Tibetan Plateau ◽

Temperature Relation ◽

The Core ◽

The Past ◽

Ice Cap ◽

The Qilian Mountains

Α δ18O record from Dunde Ice Cap, located in the Qilian mountains on the northeastern margin of the Tibetan Plateau, has been analyzed and interpreted. With an ice temperature of –7.3°C at a depth of 10 m and –4.7°C at the bottom of the ice cap, and an accumulation rate of 400 mm a−1, the Dunde core has provided interesting results. The upper part of this core, core D-l, can be easily dated by a combination of δ18O, microparticle concentration and conductivity. It can also be dated as far back as 4550 BP by counting dust layers in ice. Based on the time scale established by the above methods and on the δ18O–temperature relation, the δ18O fluctuations in the upper 120 m of the core can be interpreted as mainly due to climatic changes during the past ~ 5000 years. The warmest periods in the past ~ 5000 years in the core were found to be centered on the present, 3000, and 4100 BP, and the colder periods center around 500, 1200, 4000, and 4500 BP. It is clear from the ice-core record that the Little Ice Age was only one of many cold periods in the past, although it was the coldest period in the past 500 years.

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Snow cover sensitivity to black carbon deposition in the Himalayas: from atmospheric and ice core measurements to regional climate simulations

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-4237-2014 ◽

2014 ◽

Vol 14 (8) ◽

pp. 4237-4249 ◽

Cited By ~ 54

Author(s):

M. Ménégoz ◽

G. Krinner ◽

Y. Balkanski ◽

O. Boucher ◽

A. Cozic ◽

...

Keyword(s):

Snow Cover ◽

Black Carbon ◽

Regional Climate ◽

Ice Core ◽

Ice Cores ◽

Short Wave ◽

Wave Radiation ◽

The Tibetan Plateau ◽

Snow Cover Duration ◽

The Impact

Abstract. We applied a climate-chemistry global model to evaluate the impact of black carbon (BC) deposition on the Himalayan snow cover from 1998 to 2008. Using a stretched grid with a resolution of 50 km over this complex topography, the model reproduces reasonably well the remotely sensed observations of the snow cover duration. Similar to observations, modelled atmospheric BC concentrations in the central Himalayas reach a minimum during the monsoon and a maximum during the post- and pre-monsoon periods. Comparing the simulated BC concentrations in the snow with observations is more challenging because of their high spatial variability and complex vertical distribution. We simulated spring BC concentrations in surface snow varying from tens to hundreds of μg kg−1, higher by one to two orders of magnitude than those observed in ice cores extracted from central Himalayan glaciers at high elevations (>6000 m a.s.l.), but typical for seasonal snow cover sampled in middle elevation regions (<6000 m a.s.l.). In these areas, we estimate that both wet and dry BC depositions affect the Himalayan snow cover reducing its annual duration by 1 to 8 days. In our simulations, the effect of anthropogenic BC deposition on snow is quite low over the Tibetan Plateau because this area is only sparsely snow covered. However, the impact becomes larger along the entire Hindu-Kush, Karakorum and Himalayan mountain ranges. In these regions, BC in snow induces an increase of the net short-wave radiation at the surface with an annual mean of 1 to 3 W m−2 leading to a localised warming between 0.05 and 0.3 °C.

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Burning-derived vanillic acid in an Arctic ice core from Tunu, Northeastern Greenland

10.5194/cp-2018-46 ◽

2018 ◽

Cited By ~ 1

Author(s):

Mackenzie M. Grieman ◽

Murat Aydin ◽

Joseph R. McConnell ◽

Eric S. Saltzman

Keyword(s):

Biomass Burning ◽

Vanillic Acid ◽

Boreal Forests ◽

Trajectory Analysis ◽

Source Region ◽

Ice Core ◽

The Past ◽

Core Site ◽

Arctic Ice ◽

Air Mass Trajectory

Abstract. In this study, vanillic acid was measured in the Tunu ice core from northeastern Greenland in samples covering the past 1700 years. Vanillic acid is an aerosol-borne aromatic methoxy acid, produced by the combustion of lignin during biomass burning. Air mass trajectory analysis indicates that North American boreal forests are likely the major source region for biomass burning aerosols deposited to the ice core site. Vanillic acid levels in the Tunu ice core range from

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Trends and features of climatic changes in the past 5000 years recorded by the Dunde ice core

Annals of Glaciology ◽

10.1017/s0260305500004766 ◽

1992 ◽

Vol 16 ◽

pp. 21-24 ◽

Cited By ~ 77

Author(s):

Yao Tandong ◽

L. G. Thompson

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Climatic Changes ◽

Ice Age ◽

The Tibetan Plateau ◽

Temperature Relation ◽

The Core ◽

The Past ◽

Ice Cap ◽

The Qilian Mountains

Α δ18O record from Dunde Ice Cap, located in the Qilian mountains on the northeastern margin of the Tibetan Plateau, has been analyzed and interpreted. With an ice temperature of –7.3°C at a depth of 10 m and –4.7°C at the bottom of the ice cap, and an accumulation rate of 400 mm a−1, the Dunde core has provided interesting results. The upper part of this core, core D-l, can be easily dated by a combination of δ18O, microparticle concentration and conductivity. It can also be dated as far back as 4550 BP by counting dust layers in ice. Based on the time scale established by the above methods and on the δ18O–temperature relation, the δ18O fluctuations in the upper 120 m of the core can be interpreted as mainly due to climatic changes during the past ~ 5000 years. The warmest periods in the past ~ 5000 years in the core were found to be centered on the present, 3000, and 4100 BP, and the colder periods center around 500, 1200, 4000, and 4500 BP. It is clear from the ice-core record that the Little Ice Age was only one of many cold periods in the past, although it was the coldest period in the past 500 years.

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The Oxford Handbook of American Women's and Gender History

10.1093/oxfordhb/9780190222628.001.0001 ◽

2018 ◽

Keyword(s):

Women Of Color ◽

Historical Record ◽

Historical Evidence ◽

Gender History ◽

Artistic Production ◽

The Past ◽

History Of ◽

Cultural Power ◽

And Gender ◽

Free Women

The Oxford Handbook of American Women’s and Gender History boldly interprets the history of diverse women and how ideas about gender shaped their access to political and cultural power in North America over six centuries. In twenty-nine chapters, the Handbook showcases women’s and gender history as an integrated field with its own interpretation of the past, focused on how gender influenced people’s lives as they participated in migration, colonialism, trade, warfare, artistic production, and community building. Organized chronologically and thematically, the Handbook’s six sections allow readers to consider historical continuities of gendered power as well as individual innovations and ruptures in gender systems. Theoretically cutting edge, each chapter bursts with fascinating historical characters, from young Chicanas transforming urban culture, to free women of color forging abolitionist doctrines, to Asian migrant women defending the legitimacy of their marriages, to working-class activists mobilizing international movements, to transwomen fleeing incarceration. Together, their lives constitute the history of a continent. Leading scholars from multiple generations demonstrate the power of innovative research to excavate a history hidden in plain sight. Scrutinizing silences in the historical record, from the inattention to enslaved women’s opinions to the suppression of Indian women’s involvement in border diplomacy, the authors challenge the nature of historical evidence and remap what counts in our interpretation of the past. They demonstrate a way to extend this more capacious vision of history forward, setting an intellectual agenda informed by intersectionality and transnationalism, and new understandings of sexuality.

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Improved estimates of preindustrial biomass burning reduce the magnitude of aerosol climate forcing in the Southern Hemisphere

Science Advances ◽

10.1126/sciadv.abc1379 ◽

2021 ◽

Vol 7 (22) ◽

pp. eabc1379

Author(s):

Pengfei Liu ◽

Jed O. Kaplan ◽

Loretta J. Mickley ◽

Yang Li ◽

Nathan J. Chellman ◽

...

Keyword(s):

Southern Hemisphere ◽

Radiative Forcing ◽

Ice Core ◽

Ice Cores ◽

Terrestrial Ecosystems ◽

Rapid Expansion ◽

Past Century ◽

Fire Emissions ◽

The Past ◽

Fire Activity

Fire plays a pivotal role in shaping terrestrial ecosystems and the chemical composition of the atmosphere and thus influences Earth’s climate. The trend and magnitude of fire activity over the past few centuries are controversial, which hinders understanding of preindustrial to present-day aerosol radiative forcing. Here, we present evidence from records of 14 Antarctic ice cores and 1 central Andean ice core, suggesting that historical fire activity in the Southern Hemisphere (SH) exceeded present-day levels. To understand this observation, we use a global fire model to show that overall SH fire emissions could have declined by 30% over the 20th century, possibly because of the rapid expansion of land use for agriculture and animal production in middle to high latitudes. Radiative forcing calculations suggest that the decreasing trend in SH fire emissions over the past century largely compensates for the cooling effect of increasing aerosols from fossil fuel and biofuel sources.

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