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GNSS Station at the Pyramid International Laboratory – Observatory (Khumbu Valley - Nepal)

In 2011, within the framework of the SHARE project a new GPS receiver Leica GRX 1200 + GNSS was installed on a hill near the Pyramid Laboratory. Coordinates: Latitude: 27°57'33.23 Longitude: 86°48'47.14 Elevation: 4994.59 (above the GRS84 Ellipsoid)

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Geospatial Rainfall Modelling at Eastern Nepalese Highland from Ground Environmental Data

The study presents a geospatial knowledge transfer framework by accommodating precipitation maps for the Eastern Nepalese Highland (ENH) across an area of about 100,000 km2. For this remote area, precipitation–elevation relationships are not homogeneously distributed, but present a chaotic gradient of correlations at altitude ranges. This is mainly due to impervious orography, extreme climate, and data scarcity (most of the rain gauges in Himalaya are located at valley bottoms). Applying geostatistical models (e.g. multivariate geospatial approaches) is difficult in these zones. This makes the ENH an interesting test area where we obtained monthly precipitation spatial patterns for a 30-year period (1961–1990). The aim was to both capture orographic meso-a spatial regimen (~30 km) and local pattern variability (~10 km). Data from 58 FAO raingauges were used plus data from an atmospheric weather station (AWS Pyramid) operating at 5,050 m a.s.l., used to compensate the gap of precipitation pattern presents in the area surrounding the Mount Everest. In these complex orographically remote areas of the Himalayas, monsoon precipitation systems exhibit important topographical interactions and spatial correlations, depending on the scale at which the primary variable (e.g., precipitation) and co-variables (e.g., elevation) are recorded and analysed. Precipitations were assessed for months—May, July and September—representative of the monsoon season. For the rainiest month (July), cokriging indicated a range of precipitation values from ~100 mm over the Tibetan Plateau to ~500 mm in the southern part of Nepal, up to ~900 mm towards the pre-Himalayan range. For July, cokriging precipitation map also showed correspondence with the map of vegetation pattern, and therein lies the clue to using multivariate geostatistical models as flexible approaches for estimating precipitation spatial patterns in remote areas.

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A new estimation of the recent tropospheric molecular hydrogen budget using atmospheric observations and variational inversion

This paper presents an analysis of the recent tropospheric molecular hydrogen (H2) budget with a particular focus on soil uptake and European surface emissions. A variational inversion scheme is combined with observations from the RAMCES and EUROHYDROS atmospheric networks, which include continuous measurements performed between mid-2006 and mid-2009. Net H2 surface flux, then deposition velocity and surface emissions and finally, deposition velocity, biomass burning, anthropogenic and N2 fixation-related emissions were simultaneously inverted in several scenarios. These scenarios have focused on the sensibility of the soil uptake value to different spatio-temporal distributions. The range of variations of these diverse inversion sets generate an estimate of the uncertainty for each term of the H2 budget. The net H2 flux per region (High Northern Hemisphere, Tropics and High Southern Hemisphere) varies between ?8 and +8 Tg yr?1. The best inversion in terms of fit to the observations combines updated prior surface emissions and a soil deposition velocity map that is based on bottom-up and top-down estimations. Our estimate of global H2 soil uptake is ?59±9 Tg yr?1. Forty per cent of this uptake is located in the High Northern Hemisphere and 55% is located in the Tropics. In terms of surface emissions, seasonality is mainly driven by biomass burning emissions. The inferred European anthropogenic emissions are consistent with independent H2 emissions estimated using a H2/CO mass ratio of 0.034 and CO emissions within the range of their respective uncertainties. Additional constraints, such as isotopic measurements would be needed to infer a more robust partition of H2 sources and sinks.

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Optimal Estimation of the Surface Fluxes of Methyl Chloride using a 3-D Global Chemical Transport Model,

Methyl chloride (CH3Cl) is a chlorine-containing trace gas in the atmosphere contributing significantly to stratospheric ozone depletion. Large uncertainties in estimates of its source and sink magnitudes and temporal and spatial variations currently exist. GEIA inventories and other bottom-up emission estimates are used to construct a priori maps of the surface fluxes of CH3Cl. The Model of Atmospheric Transport and Chemistry (MATCH), driven by NCEP interannually varying meteorological data, is then used to simulate CH3Cl mole fractions and quantify the time series of sensitivities of the mole fractions at each measurement site to the surface fluxes of various regional and global sources and sinks. We then implement the Kalman filter (with the unit pulse response method) to estimate the surface fluxes on regional/global scales with monthly resolution from January 2000 to December 2004. High frequency observations from the AGAGE, SOGE, NIES, and NOAA/ESRL HATS in situ networks and low frequency observations from the NOAA/ESRL HATS flask network are used to constrain the source and sink magnitudes. The inversion results indicate global total emissions around 4100 ± 470 Gg yr-1 with very large emissions of 2200 ± 390 Gg yr-1 from tropical plants, which turn out to be the largest single source in the CH3Cl budget. Relative to their a priori annual estimates, the inversion increases global annual fungal and tropical emissions, and reduces the global oceanic source. The inversion implies greater seasonal and interannual oscillations of the natural sources and sink of CH3Cl compared to the a priori. The inversion also reflects the strong effects of the 2002/2003 globally widespread heat waves and droughts on global emissions from tropical plants, biomass burning and salt marshes, and on the soil sink.

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Remote Sensing Application to The Knowledge Of Enviromental Dynamics For A Project Of Management Planning In Central Karakoram National Park,Pakistan

The aim of this contribution is to present the research activities which will be carried out in the frame of the Project “Institutional Consolidation for the Coordinated and Integrated Monitoring of Natural Resources towards Sustainable Development and Environmental Conservation in the Hindu Kush - Karakoram-Himalaya Mountain Complex”. The Project will be performed within the cooperation of four scientific partners: IUCN (International Union for the Conservation of Nature and Natural Resources), ICIMOD (International Centre for Integrated Mountain Development), Ev-K2-CNR and CESVI (NGO, Cooperazione e Sviluppo, onlus) with the involvement of international researchers. The local management will be provided in Nepal by the Sagarmatha National Park (SNP), in Pakistan by the Central Karakoram National Park (CNKP) and in Tibet Autonomous Region (China) by the Quomolongma Nature Preserve (QNP). This contribution will provide an overview about the research issues (on forests, biodiversity, glacier changes, livelihoods) mainly based on remote sensing technologies which could be successfully applied on CNKP. The need for integrating remote sensing data and field activities are presented as well. The applied image processing techniques (i.e. radiometric normalization, image geometric rectification and thematic classification) are introduced with an emphasis on the key role played by acquiring field data and evaluating the accuracy. The basis of this discussion is the creation of some base thematic maps realised mainly from remote sensing data.

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Sedimentary evidence for recent increases in production in Tibetan plateau lakes

The Tibetan Plateau is a vast, elevated plateau in Central Asia with an average elevation of over 4,500 m and contains the world’s third largest store of ice. It occupies a climatic transition zone between the Asian monsoons and westerly airflow. As a result of this location, the region is sensitive to changes in climate on timescales of decades to millennia and longer. Long-term data are needed to evaluate climatic changes and their impact on ecosystems, but in areas as remote as the Tibetan Plateau, long-term instrumental records of environmental change are geographically sparse and monitoring has only been undertaken in recent times. Paleolimnological approach might be then one of the few means by which environmental variability can be ascertained at scales that allow comparison with contemporary monitoring data and future model projections. Therefore, a paleolimnological study was undertaken in eight different lakes sampled along a North–South transect across the Tibetan Plateau analysing geochemistry and algal pigment in order to assess longer term variability in the trophic condition of these systems and their potential to reconstruct changes in relation to recent climate evolution and possible human impacts. Chronologies for the last century were based on radiometric techniques (210Pb, 241Am and 137Cs). Results show that inorganic sediment dominates the composition of the cores used in this study. Organic carbon constitutes less than 5% d.w. in all the lake cores, except for Kemen Co core where concentrations up to 14% d.w., are observed. Corg:N ratios are generally in the order of 5–10, indicating that autochthonous algal production is the principal biological source of organic matter. Pigment preservation is generally good throughout the cores from all lakes as shown by the 430:410 nm ratio that is generally around 1.0 or higher. Six out of eight lakes show an increase in primary production in recent times. High pre-1800 AD pigment concentrations were detected only in Qinghai Lake. Since most of the lakes show a similar behaviour in the most recent section of the core, we interpret this as a response to climate and land-use changes that have increased autochthonous production throughout the Tibetan Plateau.

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Spatial distribution of debris thickness and melting from remote-sensing and meteorological data, at debris-covered Baltoro glacier, Karakoram, Pakistan

A distributed surface energy-balance study was performed to determine sub-debris ablation across a large part of Baltoro glacier, a wide debris-covered glacier in the Karakoram range, Pakistan. The study area is similar to 124 km(2). The study aimed primarily at analyzing the influence of debris thickness on the melt distribution. The spatial distribution of the physical and thermal characteristics of the debris was calculated from remote-sensing (ASTER image) and field data. Meteorological data from an automatic weather station at Urdukas (4022 m a.s.l.), located adjacent to Baltoro glacier on a lateral moraine, were used to calculate the spatial distribution of energy available for melting during the period 1-15 July 2004. The model performance was evaluated by comparisons with field measurements for the same period. The model is reliable in predicting ablation over wide debris-covered areas. It underestimates melt rates over highly crevassed areas and water ponds with a high variability of the debris thickness distribution in the vicinity, and over areas with very low debris thickness (<0.03 m). We also examined the spatial distribution of the energy-balance components (global radiation and surface temperature) over the study area. The results allow us to quantify, for the study period, a meltwater production of 0.058 km(3).

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The determination of a regional atmospheric background mixing ratio for anthropogenic greenhouse gases: a comparison of two independent methods

Halocarbons are powerful greenhouse gases capable of significantly influencing the radiative forcing of the Earth’s atmosphere. Halocarbons are monitored in several stations which are globally distributed in order to assess long term atmospheric trends and to identify source regions. However, to achieve these aims the definition of background mixing ratios, i.e. the mixing ratio in a given air mass when the recent contribution of local sources is absent, is necessary. This task can be accomplished using different methods. This paper presents a statistical methodology that has been devised specifically for a mountain site located in Continental Europe (Monte Cimone, Italy), characterised by the vicinity of strong sources. The method involves the decomposition of the observed data distribution into a Gaussian distribution, representative of background values, and a Gamma distribution, ascribable to contribution from stronger sources. The method has been applied to a time series from a European marine remote station (Mace Head, Ireland) as well as to time series from Monte Cimone. A comparison of the methodology described in this paper with a well-established meteorological filtering procedure at Mace Head has shown an excellent agreement. A comparison of the baselines at Mace Head, Mt. Cimone and the Swiss alpine station of the Jungfraujoch highlighted the occurrence of a specific background concentration. Although this paper presents the application of the method to three hydrofluorocarbons, the proposed methodology can be extended to any long lived atmospheric component for which a long term time series is available and at any location even if affected by strong source regions.

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Analysis of glacial meltwater in Bagrot Valley, Karakoram, based on short term ablation and debris cover observations on Hinarche Glacier

People in the Karakoram use discharge from glaciers during summer for irrigation and other purposes. While the glacial meltwater supply during hot and dry periods will vary as a result of climate change, Karakoram glaciers so far have not shown a consistent reaction to climatic change, although climate scenarios indicate severe future impacts in the high-elevation regions of the Himalaya and Karakoram. Field measurements on Hinarche Glacier in Bagrot Valley are combined with remote sensing information and climate observations to investigate the meltwater production of the glacier and estimate the meltwater discharge in the valley. Special emphasis was placed on ice melt beneath supraglacial debris, which is the common process on the glacier tongues in the region. The calculated annual meltwater production of about 135 million m3 for Hinarche Glacier shows the order of magnitude for glacier runoff in such environments. Glacial meltwater production is about 300 million m3 per year for the entire valley under balanced conditions. This analysis serves as a basis for further investigations concerning temporal meltwater variability and potential water usage by the local population.

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European Emissions of Halogenated Greenhouse Gases Inferred from Atmospheric Measurements

European emissions of nine representative halocarbons (CFC-11, CFC-12, Halon 1211, HCFC-141b, HCFC-142b, HCFC-22, HFC-125, HFC-134a, HFC-152a) are derived for the year 2009 by combining long-term observations in Switzerland, Italy, and Ireland with campaign measurements from Hungary. For the first time, halocarbon emissions over Eastern Europe are assessed by top-down methods, and these results are compared to Western European emissions. The employed inversion method builds on least-squares optimization linking atmospheric observations with calculations from the Lagrangian particle dispersion model FLEXPART. The aggregated halocarbon emissions over the study area are estimated at 125 (106–150) Tg of CO2 equiv/y, of which the hydrofluorocarbons (HFCs) make up the most important fraction with 41% (31–52%). We find that chlorofluorocarbon (CFC) emissions from banks are still significant and account for 35% (27–43%) of total halocarbon emissions in Europe. The regional differences in per capita emissions are only small for the HFCs, while emissions of CFCs and hydrochlorofluorocarbons (HCFCs) tend to be higher in Western Europe compared to Eastern Europe. In total, the inferred per capita emissions are similar to estimates for China, but 3.5 (2.3–4.5) times lower than for the United States. Our study demonstrates the large benefits of adding a strategically well placed measurement site to the existing European observation network of halocarbons, as it extends the coverage of the inversion domain toward Eastern Europe and helps to better constrain the emissions over Central Europe.

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