Meteorological Features at 6523 m of Mt.Qomolangma(Everest)between 1 May and 22 July 2005

Mt. Qomolangma (Everest), the highest mountain peak in the world, has little been studied extensively from a meteorological perspective, mostly because of the remoteness of the region and the re-sultant lack of meteorological data. An automatic weather station (AWS), the highest in the world, was set up on 27 April 2005 at the Ruopula Pass (6523 m asl) on the northern slope of Mt. Qomolangma by the team of integrated scientific expedition to Mt. Qomo-langma. Here its meteorological characteristics were analyzed according to the 10-minute-averaged and 24-hour records of air temperature, relative humidity, air pressure and wind from 1 May to 22 July 2005. It is shown that at 6523 m of Mt. Qomolangma, these meteorological elements display very obvious diurnal variations, and the character of averaged diurnal variation is one-peak-and-one-vale for air tem-perature, one-vale for relative humidity, two-peak-and- two-vale for air pressure, and one-peak with day-night asymmetry for wind speed. In the 83 days, all the air temperature, relative hu-midity and air pressure increased with some dif-ferent fluctuations, while wind speed decreased gradually and wind direction turned from north to south. The variations of relative humidity had great fluctuations and obvious local differences. Then thepaper discusses the reason for the characters of diurnal and daily variations. Compared with the corresponding records in May 1960, 5-day-averaged maximums, minimums and diurnal variations of air temperature in May 2005 were apparently lower.

Review of the studies on climate change since the last inter-glacial period on the Tibetan Plateau

As the ＂Third Pole＂ of the world, the Tibetan Plateau has important effects on climate of its surrounding areas and even the whole world. Many results have been achieved on climate change since the last inter-glacial period in recent decades from ice core, tree-ring and lake sediment records over the Tibetan Plateau. In this paper, we review these achievements, especially those in the special periods. During the last inter-glacial period, temperature went down rapidly and went up slowly. The temperature record of the last glacial period is consistent with Greenland ice core records, also having own features over the Tibetan Plateau. Younger Dryas event agrees with the records from Europe and Greenland. Generally speaking, it is warm in the Holocene, and temperature has been rising gradually in the last 2000 years and gone up rapidly in recent decades. Climate changes on different time scales on the Tibetan Plateau occurred earlier and the change amplitude is larger than those in other parts of China.

Soluble species in aerosols collected on the route of the Second Chinese National Arctic Research Expedition

Aerosol samples are collected on the route of the Second Chinese National Arctic Research Expedition from July 15 to September 28,2003. The concentration of water soluble ions （Na^＋, NH4^＋, Ca^2＋, Cl^-, MSA , SO4^2- and so on） are analyzed. By correlation analysis, the ions can be divided into three groups ： （ 1 ） Na^＋ , Mg^2＋, K^＋, Ca^2＋, Cl^-, SO4^2-, mainly from sea salt; （2） NH4^＋, NO3^-, markedly from coastal regions of the continents ; （3） Acetate, MSA, C2O4^2-, from other sources. Marine aerosols are the dominant origin, Cl^- and Na^＋ are the most dominant anion and cation, respectively and these two ions （ Na^＋ ＋Cl^- ） account for 55. 6% of the total aerosol loading. The mean equivalence ratio of NH4^＋/SO4^2- is 0.45, we suggest that ammonium and sulfate exist mainly as NH4HSO4. The concentration of NO3- shows three different patterns on the route of expedition： Japan Sea with median value of 15.2 neq · m^ -3 ; Sea of Okhostk and Bering Sea of 1.8 neq ·m ^-3 and Arctic Ocean of 0.4 neq · m^-3 Bering Sea is a high MSA area. Through the comparison of the concentration of main water soluble ions between the First and Second Chinese National Arctic Research Expedition, the variation matches each other.