Heavy rainfall events recorded in sediments of the TT Lake (southern-central Tibetan Plateau) since AD 440

Abstract HKT-ISTP 2013 B

Flamingo: Test zum sinnentnehmenden Lesen

Pilotstudie eines Tests zum sinnentnehmenden Lesen in Integrationskurses mit Alphabetisierungsschwerpunk

Modelling Energy Demand Response Using Long-Short Term Memory Neural Networks

We propose a method for detecting and forecasting events of high energy demand, which are managed at the national level in demand side response programmes, such as the UK Triads. The methodology consists of two stages: load forecasting with long short-term memory neural network and dynamic filtering of the potential highest electricity demand peaks by using the exponential moving average. The methodology is validated on real data of a UK building management system case study. We demonstrate successful forecasts of Triad events with RRMSE ≈ 2.2% and MAPE ≈ 1.6% and general applicability of the methodology for demand side response programme management, with reduction of energy consumption and indirect carbon emissions

Forest Shink Plan Using a Carbon Offset System

In April 2005, Canada announced the introduction of new systems that could make the best use of market mechanisms, such as the Climate Fund, the Large Final Emitter System, and the Carbon Offset System, in order to achieve the reductions quota during the first commitment period (2008-2012). The Carbon Offset System has very high potential as a system able to push forward the forest sink policy, as it can help companies obtain credits for the GHG sink through forest sink activities recognized by the Kyoto Protocol (Paragraph 3 and 4, Clause 3). It also enables companies to trade GHG sink credits through the domestic emissions trade market. If the Carbon Offset System, which fully uses market mechanisms, is to be applied in Korea during the second commitment period (2013-2017) when Korea will have to deal with the obligations to reduce GHG emissions, it will be applied mostly to the expansion of the forest sink, through active forest management activities, such as afforestation, reforestation, and deforestation － given Korea has far fewer forest areas than Canada. In this case, it will be possible to increase the efficiency of the system by designing and operating it in a manner suitable for the conditions in Korea, including issuing domestic GHG sink credits to each sink developed through forest management, purchasing the credits, or providing additional subsidies. Forest owners might receive economic incentives through this, and it can also encourage new outside investments, such as forestry investments made by enterprises as part of their social contribution efforts

A multi-proxy approach to reconstruct hydrological changes and Holocene climate development of Nam Co, Central Tibet

Holocene lake level fluctuations were reconstructed from a 2.7-m sediment core from Nam Co, Central Tibet, China dating to > 7.2 cal ka BP. Results were compared to existing lake records from the Tibetan Plateau to infer variations in the strength of the Asian Monsoon. Geomorphological features in the Nam Co catchment, such as beach ridges and lake terraces, indicate high lake stands during the late Glacial. A major low stand is suggested for the Last Glacial Maximum (LGM). Sands and sandy silts at the base of the core are transgressive facies, with material transported by melt water and deposited under rising lake level conditions that followed the LGM low stand. Variations in grain size, major elements, biomarker stable isotopes and minerals in the core suggest a climate evolution reflected in at least five depositional units and subunits. Sediments in Unit I (similar to 7.2 to similar to 5.4 cal ka BP) were deposited at highest lake levels. Large amounts of allogenic minerals and allochthonous organic matter suggest high precipitation and melt water input, implying positive water balance. Increasing aquatic productivity points to favourable environmental conditions. Unit II (similar to 5.4 to similar to 4.0 cal ka BP) marks a transition between favourable, stable hydrological conditions and lake level decrease. Lower lake levels were a consequence of drier climate with less monsoonal precipitation, higher evaporation rates, and increased moisture recycling in the catchment. Unit III (similar to 4.0 to similar to 1.4 cal ka BP) reflects the driest periods recorded, at similar to 3.7 cal ka BP and 1.6 cal ka BP. Lake shrinkage and salinization was interrupted as suggested by the deposition of Unit IV (similar to 1.4 to similar to 0.8 cal ka BP), when increased precipitation and runoff that might be related to the Medieval Warm Period, led to a stable, but still low lake level. Unit V (800 cal years BP-present) is characterized by progressive lake shrinkage due to intense evaporation. Large fluctuations in geochemical variables indicate humid and arid periods, respectively, at Nam Co between similar to 450 and similar to 200 cal years BP, with the latter assumed to correspond to the Little Ice Age. Modern hydrological data indicate the lake level is rising. Comparison of the Nam Co record with other lake records from the Tibetan Plateau suggests general agreement with the broader picture of Holocene environmental evolution. The timing of dry and wet climate conditions at lake sites across Tibet indicates a gradually decreasing influence of the southern monsoon during the Holocene, from NW to SE. Nevertheless, further research is needed to improve our understanding of Holocene spatio-temporal hydrological variations across the Asian continent

Climate change on the Tibetan Plateau in response to shifting atmospheric circulation since the LGM

The Tibetan Plateau (TP) is primarily influenced by the northern hemispheric middle latitude Westerlies and the Indian summer monsoon (ISM). The extent, long-distance effects and potential long-term changes of these two atmospheric circulations are not yet fully understood. Here, we analyse modern airborne pollen in a transition zone of seasonally alternating dominance of the Westerlies and the ISM to develop a pollen discrimination index (PDI) that allows us to distinguish between the intensities of the two circulation systems. This index is applied to interpret a continuous lacustrine sedimentary record from Lake Nam Co covering the past 24 cal kyr BP to investigate long-term variations in the atmospheric circulation systems. Climatic variations on the central TP widely correspond to those of the North Atlantic (NA) realm, but are controlled through different mechanisms resulting from the changing climatic conditions since the Last Glacial Maximum (LGM). During the LGM, until 16.5 cal kyr BP, the TP was dominated by the Westerlies. After 16.5 cal kyr BP, the climatic conditions were mainly controlled by the ISM. From 11.6 to 9 cal kyr BP, the TP was exposed to enhanced solar radiation at the low latitudes, resulting in greater water availability