Rapid thermokarst evolution during the mid-Holocene in Central Yakutia, Russia

The reconstruction of Holocene thermokarst landform evolution is important to understand the potential impact of current global climate change on permafrost regions. A multi-proxy approach was applied to analyse the sedimentological and biogeochemical characteristics as well as pollen and lacustrine microfossils of a core profile drilled in a small pingo within a large Central Yakutian thermokarst basin (alas). Age–depth modelling with macrofossil 14C ages reveals high thermokarst deposit sedimentation rates and a complete thermokarst sequence spanning about 900 years during the mid-Holocene between ~6750 and 5870 cal. yr BP. In total, three stages of thermokarst landscape evolution have been identified. Thermokarst processes were initiated at ⩽6750 to 6500 cal. yr BP. Terrestrial conditions changed quickly to lacustrine conditions, and a thermokarst lake rapidly emerged and grew to an estimated size of 120–600 m diameter and 7.5–15 m depth during only ~150 years between ~6500 and 6350 cal. yr BP. The decline of thermokarst processes and lake decrease may have been affected by local hydrological conditions between ~6350 and 5870 cal. yr BP but ceased completely after 5870 cal. yr BP, likely due to climatic changes. Clear evidence for long-lasting and stable lacustrine conditions was not obtained. The study emphasises that short-term warming led to very active permafrost degradation and rapid but locally variable modification of alas and thermokarst evolution.

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Co-production of permafrost degradation impact assessment for permafrost environmental utilization and conservation

Impact ◽

10.21820/23987073.2020.6.29 ◽

2020 ◽

Vol 2020 (6) ◽

pp. 29-31

Author(s):

Yoshihiro Iijima

Keyword(s):

Climate Change ◽

Global Climate ◽

Associate Professor ◽

Living Environment ◽

Permafrost Region ◽

Permafrost Degradation ◽

Local Populations ◽

Local Residents ◽

Regions Of Russia ◽

Permafrost Regions

Permafrost plays a hugely significant role in sustaining the global climate for many reasons. As it thaws, gases (usually methane and carbon dioxide) that have lain trapped underneath the ice for millennia are released. These gases then enter the atmosphere and accelerate global warming which leads to more permafrost degradation and it eventually becomes a problem which exacerbates itself. In recent times, the warming and thawing of the surface layer of the permafrost region in northeastern Eurasia has caused serious impacts on the living environment of local residents. In many ways, the thawing of permafrost can be seen as a new natural disaster and, as such, it requires understanding from local populations to put measures in place to mitigate the effects. Associate Professor Yoshihiro Iijima is part of a international team of researchers investigating the effects of climate change on the permafrost regions of Russia and Mongolia. The findings could help local populations introduce conservation activities to their societies

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Using syndromic measures of mortality to capture the dynamics of COVID-19 in Java, Indonesia, in the context of vaccination rollout

BMC Medicine ◽

10.1186/s12916-021-02016-2 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Bimandra A. Djaafara ◽

Charles Whittaker ◽

Oliver J. Watson ◽

Robert Verity ◽

Nicholas F. Brazeau ◽

...

Keyword(s):

Rural Areas ◽

Vaccination Campaign ◽

Control Measures ◽

Additional Insight ◽

Short Term ◽

If Current ◽

Vaccine Impact ◽

Potential Impact ◽

The Impact ◽

Insight Into

Abstract Background As in many countries, quantifying COVID-19 spread in Indonesia remains challenging due to testing limitations. In Java, non-pharmaceutical interventions (NPIs) were implemented throughout 2020. However, as a vaccination campaign launches, cases and deaths are rising across the island. Methods We used modelling to explore the extent to which data on burials in Jakarta using strict COVID-19 protocols (C19P) provide additional insight into the transmissibility of the disease, epidemic trajectory, and the impact of NPIs. We assess how implementation of NPIs in early 2021 will shape the epidemic during the period of likely vaccine rollout. Results C19P burial data in Jakarta suggest a death toll approximately 3.3 times higher than reported. Transmission estimates using these data suggest earlier, larger, and more sustained impact of NPIs. Measures to reduce sub-national spread, particularly during Ramadan, substantially mitigated spread to more vulnerable rural areas. Given current trajectory, daily cases and deaths are likely to increase in most regions as the vaccine is rolled out. Transmission may peak in early 2021 in Jakarta if current levels of control are maintained. However, relaxation of control measures is likely to lead to a subsequent resurgence in the absence of an effective vaccination campaign. Conclusions Syndromic measures of mortality provide a more complete picture of COVID-19 severity upon which to base decision-making. The high potential impact of the vaccine in Java is attributable to reductions in transmission to date and dependent on these being maintained. Increases in control in the relatively short-term will likely yield large, synergistic increases in vaccine impact.

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Chronology of Lake El'gygytgyn sediments – a combined magnetostratigraphic, palaeoclimatic and orbital tuning study based on multi-parameter analyses

Climate of the Past ◽

10.5194/cp-9-2413-2013 ◽

2013 ◽

Vol 9 (6) ◽

pp. 2413-2432 ◽

Cited By ~ 44

Author(s):

N. R. Nowaczyk ◽

E. M. Haltia ◽

D. Ulbricht ◽

V. Wennrich ◽

M. A. Sauerbrey ◽

...

Keyword(s):

Global Climate ◽

Far East ◽

Climatic Conditions ◽

Sedimentation Rates ◽

Scientific Drilling ◽

Lake El’Gygytgyn ◽

Age Model ◽

Orbital Tuning ◽

Lake Floor ◽

The Impact

Abstract. A 318-metre-long sedimentary profile drilled by the International Continental Scientific Drilling Program (ICDP) at Site 5011-1 in Lake El'gygytgyn, Far East Russian Arctic, has been analysed for its sedimentologic response to global climate modes by chronostratigraphic methods. The 12 km wide lake is sited off-centre in an 18 km large crater that was created by the impact of a meteorite 3.58 Ma ago. Since then sediments have been continuously deposited. For establishing their chronology, major reversals of the earth's magnetic field provided initial tie points for the age model, confirming that the impact occurred in the earliest geomagnetic Gauss chron. Various stratigraphic parameters, reflecting redox conditions at the lake floor and climatic conditions in the catchment were tuned synchronously to Northern Hemisphere insolation variations and the marine oxygen isotope stack, respectively. Thus, a robust age model comprising more than 600 tie points could be defined. It could be shown that deposition of sediments in Lake El'gygytgyn occurred in concert with global climatic cycles. The upper ~160 m of sediments represent the past 3.3 Ma, equivalent to sedimentation rates of 4 to 5 cm ka−1, whereas the lower 160 m represent just the first 0.3 Ma after the impact, equivalent to sedimentation rates in the order of 45 cm ka−1. This study also provides orbitally tuned ages for a total of 8 tephras deposited in Lake El'gygytgyn.

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Permafrost-Affected Soils of the Russian Arctic and their Carbon Pools

Solid Earth Discussions ◽

10.5194/sed-6-619-2014 ◽

2014 ◽

Vol 6 (1) ◽

pp. 619-655

Author(s):

S. Zubrzycki ◽

L. Kutzbach ◽

E.-M. Pfeiffer

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Sink ◽

Global Climate ◽

Fundamental Property ◽

Climate System ◽

The Arctic ◽

Quaternary Period ◽

Permafrost Regions

Abstract. Permafrost-affected soils have accumulated enormous pools of organic matter during the Quaternary Period. The area occupied by these soils amounts to more than 8.6 million km2, which is about 27% of all land areas north of 50° N. Therefore, permafrost-affected soils are considered to be one of the most important cryosphere elements within the climate system. Due to the cryopedogenic processes that form these particular soils and the overlying vegetation that is adapted to the arctic climate, organic matter has accumulated to the present extent of up to 1024 Pg (1 Pg = 1015 g = 1 Gt) of soil organic carbon stored within the uppermost three meters of ground. Considering the observed progressive climate change and the projected polar amplification, permafrost-affected soils will undergo fundamental property changes. Higher turnover and mineralization rates of the organic matter are consequences of these changes, which are expected to result in an increased release of climate-relevant trace gases into the atmosphere. As a result, permafrost regions with their distinctive soils are likely to trigger an important tipping point within the global climate system, with additional political and social implications. The controversy of whether permafrost regions continue accumulating carbon or already function as a carbon source remains open until today. An increased focus on this subject matter, especially in underrepresented Siberian regions, could contribute to a more robust estimation of the soil organic carbon pool of permafrost regions and at the same time improve the understanding of the carbon sink and source functions of permafrost-affected soils.

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Long- to short-term denudation rates in the southern Apennines: geomorphological markers and chronological constraints

Geologica Carpathica ◽

10.2478/v10096-011-0003-1 ◽

2011 ◽

Vol 62 (1) ◽

pp. 27-41 ◽

Cited By ~ 28

Author(s):

Dario Gioia ◽

Claudio Martino ◽

Marcello Schiattarella

Keyword(s):

Sediment Accumulation ◽

Radiometric Dating ◽

Sedimentation Rates ◽

Southern Apennines ◽

Short Term ◽

Small Catchment ◽

Fluvial Terraces ◽

Denudation Rates ◽

Land Surfaces

Long- to short-term denudation rates in the southern Apennines: geomorphological markers and chronological constraints Age constraints of geomorphological markers and consequent estimates of long- to short-term denudation rates from southern Italy are given here. Geomorphic analysis of the valley of the Tanagro River combined with apatite fission track data and radiometric dating provided useful information on the ages and evolution of some significant morphotectonic markers such as regional planated landscapes, erosional land surfaces and fluvial terraces. Reconstruction of paleotopography and estimation of the eroded volumes were perfomed starting from the plano-altimetric distribution of several orders of erosional land surfaces surveyed in the study area. Additional data about denudation rates related to the recent and/or active geomorphological system have been obtained by estimating the amount of suspended sediment yield at the outlet of some catchments using empirical relationships based on the hierarchical arrangement of the drainage network. Denudation rates obtained through these methods have been compared with the sedimentation rates calculated for two adjacent basins (the Pantano di San Gregorio and the Vallo di Diano), on the basis of published tephrochronological constraints. These rates have also been compared with those calculated for the historical sediment accumulation in a small catchment located to the north of the study area, with long-term exhumation data from thermochronometry, and with uplift rates from the study area. Long- and short-term denudation rates are included between 0.1 and 0.2 mm/yr, in good agreement with regional data and long-term sedimentation rates from the Vallo di Diano and the Pantano di San Gregorio Magno basins. On the other hand, higher values of exhumation rates from thermochronometry suggest the existence of past erosional processes faster than the recent and present-day exogenic dismantling. Finally, the comparison between uplift and denudation rates indicates that the fluvial erosion did not match the tectonic uplift during the Quaternary in this sector of the chain. The axial zone of the southern Apennines should therefore be regarded as a landscape in conditions of geomorphological disequilibrium.

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Long-Term Gain, Short-Term Pain: Assessing the Potential Impact of Structural Reforms in Chile

SSRN Electronic Journal ◽

10.2139/ssrn.2733584 ◽

2015 ◽

Author(s):

Marika Santoro

Keyword(s):

Structural Reforms ◽

Short Term ◽

Potential Impact

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Introduction

The Phanerozoic Carbon Cycle ◽

10.1093/oso/9780195173338.003.0003 ◽

2004 ◽

Author(s):

Robert A. Berner

Keyword(s):

Climate Change ◽

Carbon Dioxide ◽

Carbon Cycle ◽

Global Climate ◽

Geological Time ◽

Short Term ◽

Quaternary Period ◽

Geological Time Scale ◽

The Earth

The cycle of carbon is essential to the maintenance of life, to climate, and to the composition of the atmosphere and oceans. What is normally thought of as the “carbon cycle” is the transfer of carbon between the atmosphere, the oceans, and life. This is not the subject of interest of this book. To understand this apparently confusing statement, it is necessary to separate the carbon cycle into two cycles: the short-term cycle and the long-term cycle. The “carbon cycle,” as most people understand it, is represented in figure 1.1. Carbon dioxide is taken up via photosynthesis by green plants on the continents or phytoplankton in the ocean. On land carbon is transferred to soils by the dropping of leaves, root growth, and respiration, the death of plants, and the development of soil biota. Land herbivores eat the plants, and carnivores eat the herbivores. In the oceans the phytoplankton are eaten by zooplankton that are in turn eaten by larger and larger organisms. The plants, plankton, and animals respire CO2. Upon death the plants and animals are decomposed by microorganisms with the ultimate production of CO2. Carbon dioxide is exchanged between the oceans and atmosphere, and dissolved organic matter is carried in solution by rivers from soils to the sea. This all constitutes the shortterm carbon cycle. The word “short-term” is used because the characteristic times for transferring carbon between reservoirs range from days to tens of thousands of years. Because the earth is more than four billion years old, this is short on a geological time scale. As the short-term cycle proceeds, concentrations of the two principal atmospheric gases, CO2 and CH4, can change as a result of perturbations of the cycle. Because these two are both greenhouse gases—in other words, they adsorb outgoing infrared radiation from the earth surface—changes in their concentrations can involve global warming and cooling over centuries and many millennia. Such changes have accompanied global climate change over the Quaternary period (past 2 million years), although other factors, such as variations in the receipt of solar radiation due to changes in characteristics of the earth’s orbit, have also contributed to climate change.

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Long-Term Interaction

Interactive Digital Television ◽

10.4018/978-1-59904-361-6.ch010 ◽

2011 ◽

pp. 169-183

Author(s):

Christoph Haffner ◽

Thorsten Völkel

Keyword(s):

Working Memory ◽

Interactive Television ◽

Theoretical Models ◽

Short Term ◽

Time Periods ◽

Potential Impact

This chapter introduces the application of concepts for long-term interaction to support long-term relationship in the interactive television (iTV) domain. While classical interaction concepts cover short-term interaction cycles only, theoretical models for long-term interaction and relationships deal with time periods exceeding the human short-term working memory. The user must be supported by memory cues to resume interrupted long-term interactions immediately. The iTV domain offers many long-term interaction scenarios in the context of establishing long-term relationships of recipients and broadcasters. The authors adopt concepts for long-term interaction towards iTV and develop a basic classification of long-term interaction. Three scenarios within the iTV domain illustrate the potential impact for the design of iTV applications.

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