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Studies on recent climate trends from the Himalayan range are limited, and even completely absent at high elevation (> 5000 m a.s.l.). This study specifically explores the southern slopes of Mt. Everest, analyzing the time series of temperature and precipitation reconstructed from seven stations located between 2660 and 5600 m a.s.l. during 1994–2013, complemented with the data from all existing ground weather stations located on both sides of the mountain range (Koshi Basin) over the same period. Overall we find that the main and most significant increase in temperature is concentrated outside of the monsoon period. Above 5000 m a.s.l. the increasing trend in the time series of minimum temperature (+0.072 °C yr−1) is much stronger than of maximum temperature (+0.009 °C yr−1), while the mean temperature increased by +0.044 °C yr−1. Moreover, we note a substantial liquid precipitation weakening (−9.3 mm yr−1) during the monsoon season. The annual rate of decrease in precipitation at higher elevations is similar to the one at lower elevations on the southern side of the Koshi Basin, but the drier conditions of this remote environment make the fractional loss much more consistent (−47% during the monsoon period). Our results challenge the assumptions on whether temperature or precipitation is the main driver of recent glacier mass changes in the region. The main implications are the following: (1) the negative mass balances of glaciers observed in this region can be more ascribed to a decrease in accumulation (snowfall) than to an increase in surface melting; (2) the melting has only been favoured during winter and spring months and close to the glaciers terminus; (3) a decrease in the probability of snowfall (−10%) has made a significant impact only at glacier ablation zone, but the magnitude of this decrease is distinctly lower than the observed decrease in precipitation; (4) the decrease in accumulation could have caused the observed decrease in glacier flow velocity and the current stagnation of glacier termini, which in turn could have produced more melting under the debris glacier cover, leading to the formation of numerous supraglacial and proglacial lakes that have characterized the region in the last decades.

The light-absorbing properties of water-soluble brown carbon (WS-BrC) and methanol-soluble brown carbon (MeS-BrC) were studied in PM10 aerosols collected at the "Nepal Climate Observatory-Pyramid" (NCO-P) station (5079m above sea level) during the period 2013-2014. The light absorption coefficients of WS-BrC and MeS-BrC were the highest during the premonsoon season and the lowest during monsoon. MeS-BrC absorbs about 2 times higher at 365nm and about 3 times more at 550nm compared to WS-BrC. The mass absorption cross section (MAC) of WS-BrC measured at 365nm is similar to that observed previously at South Asian low-altitude sites. Fractional solar radiation absorption by BrC compared to BC considering the full solar spectrum showed that WS-BrC absorbs 4 +/- 1% and MeS-BrC absorbs 9 +/- 2% compared to BC at NCO-P. Such ratios become 8 +/- 1% (for WS-BrC respect to BC) and 17 +/- 5% (for MeS-BrC respect to BC) when accounting for correction factors proposed by previous studies to convert absorption coefficients in bulk solutions into light absorption by accumulation mode aerosol particles. These results confirm the importance of BrC in contributing to light-absorbing aerosols in this region of the world. However, the BrC absorption at 550nm appears small compared to that of BC (1-5%, or 3-9% with conversion factors), and it is lower compared to global model estimates constrained by Aerosol Robotic Network observations. Finally, our study provides no clear evidence of a change in the fractional contribution of BrC with respect to BC to light absorption in the middle troposphere respect to the Indo-Gangetic plain boundary layer.

Nextdata project aim to create a national system for retrieval, storage, access and diffusion of environmental and climate data from mountain and marine areas. For this project a database to collect paleoclimatic data from ice cores and marine cores has been developed. These data derived from drilling projects of non polar glaciers and marine sediments respectively. The activity is based on a catalog system of data and metadata called SHARE GeoNetwork, developed within the EvK2-CNR SHARE project. The database structure to stock data is based on WDB (Water and Weather Database System) architecture, a database developed from Norwegian Meteorological Institute for their operability data-center. This database was chosen because of WDB is released in according to the GNU General Public License and so completly configurable, customizable and shared; furthermore, it is developed in PostgreSQL/PostGIS and it allow to record punctual and grid type hydrometeorological data. In the first step of the project, WDB database has been customized to stock data derived from SHARE high altitude stations. Hereinafter we need to modified WDB source code in order to insert paleoclimatic data. They have a time extension that goes from current period to tens millions years ago. The “data” field of PostgreSQL has a time range from 4713 BC to 294276 AC; consequently every physical and chemical data, analyzed on ice core and marine core samples dated in different age before 4713 AC, cannot be saved into WDB database structure. We have maintained the main model but we have modified a part of the source code inserting new functions to write data into WDB, without time limits. This increase the value of temporal data aspect that is essential for paleoclimatic analysis. So, the new database system called WDBPALEO has been proposed to scientific community.

This paper introduces the development of a web- platform for sharing of environmental data in the framework of EvK2 - CNR Committee SHARE Project (Stations at High Altitude for Research on the Environment). This system intends to meet the requirement of access to the complex information concerning the acquisition of climate data at high altitude and to the data themselves. The tool that is being studied and developing proposes an environment for the research, dedicated mainly to high-altitude studies, allowing researchers to access the wealth of resources that are acquired by the climatologic stations. With regards to remote sensing data processing, the system gives the opportunity to free access to the data relevant either for atmospheric corrections or ground data calibrations. Moreover, into SHARE GeoNetwork, a specific topic is dedicated to the description of the new technologies developed in the SHARE Project. The core of the system is the catalogue of metadata based on GeoNetwork open source application, proposed on the principles of Free and Open Source Software (FOSS) and International and Open Standards for services and protocols (from ISO/TC211 and OGC). A new hierarchical structure has been implemented into SHARE for the description of metatada of the stations, sensors and measures The first release of SHARE-GeoNetwork is working from 2011 and it is accessible for public at http://geonetwork.evk2cnr.org. The integrated activity of the SHARE GeoNetwork is the implementation of the Data Base for the management of the measures acquired since 1987 by the Ev-K2 CNR Committee. These data have been ordered and stored in a coherent form by an open source database management system, Weather and Water Database (WDB), developed by the Norwegian Meteorological Institute. The geographic component of the system has been implemented and the publication of maps and georeferenced data is allowed. © 2013 SPIE.

The interpretation of firn and ice cores in high altitude sites in central Asia requires a detailed knowledge of fresh-snow chemistry, especially in the extra-monsoon season. Since 1992 the Water Research Institute of CNR has been involved in sampling and analysis of wet and snow deposition in the Himalayan area. The first campaigns, which were based at the EV-K²-CNR Pyramid site in Khumbu Valley, were focused on the southern side of the Everest groupin monsoon season with the aim of evaluating the long range transport of inorganic pollutants from the Indian subcontinent to the Himalayan range. In the following years, involving climbing expeditions, we extended our research to other regions outside the monsoon season. This approach allowed us to get a better knowledge of spatial and temporal distribution of major ions in snow deposition of the Himalayan region.

The study of the Himalayan snow deposition started on 2000 (Pumori) with the collection of snow samplings at different altitudes. The geographic isolation of Himalaya and Karakorum supplies a significant background of the xenobiotic pollutants concentration in the atmospheric depositions and an important instrument to evaluate the atmospheric processes connected to the transportation, allowing to identify the origin of the chemical species and the trace compounds. The study involves macroconstituents, acidifying species, trace metals and persistent organic micropollutants present in the sub-surfacial snow layer. As final target this study will contribute to verify the real importance of the Himalaya and Karakorum range such as barrier to the northern diffusion of pollutants produced in the Asian subcontinent, producing the Atmospheric Brown Cloud (ABC) phenomenon. These results will be compared with the measurements of the alpine snow depositions.