The Third Atmospheric Scientific Experiment for Understanding the Earth–Atmosphere Coupled System over the Tibetan Plateau and Its Effects

Abstract

61The Tibetan Plateau (TP), known as the "sensible heat pump" and the 62 "atmospheric water tower", modifies monsoon circulations and regional energy and 63 water cycles over Asia (Wu and Zhang 1998; Zhao and Chen 2001a; Wu et al. 2007; 64 Xu et al. 2008b; Zhou et al. 2009). Strong ascent over the TP may transport lower-65 tropospheric water vapor and anthropogenic pollutants into the upper troposphere-66 lower stratosphere (UT-LS), which exerts an influence on the local ozone valley 67 (Zhou et al. 1995; Liu et al. 2003; Bian et al. 2011) and the aerosol-layer 68 enhancements near the tropopause (Tobo et al. 2007; Vernier et al. 2015). The TP also In the 1990s, a longer-term field experiment was conducted over the TP with the 84 support of the Japanese Experiment on Asian Monsoon (JEXAM). It estimated the 2008a; Zhang et al. 2012; Chen et al. 2011 Chen et al. , 2013. It found diurnal variations of et al. 2013; Hu et al. 2014; Zheng et al. 2014 Zheng et al. , 2015a Zheng et al. , b, c, 2016 Guo et al. 2015; 161 Zhuo et al. 2016; Wan et al. 2017). These problems may also cause large uncertainties 162 in reanalysis datasets and satellite products (such as air temperature, soil moisture, 163 surface heat fluxes, and radiation) over the TP (Li et al. 2012; Wang et al. 2012; Zhu 164 et al. 2012; Su et al. 2013; Zeng et al. 2016). 165To promote Tibetan meteorological research, the Third Tibetan Plateau 166Atmospheric Scientific Experiment (TIPEX-III), to continue for eight to ten years, OBJECTIVES. 173The field observational objective of TIPEX-III is to constitute a 3-D observation 174 system of the land surface, PBL, troposphere, and lower stratosphere over the TP. 175This system integrates ground-, air-, and space-based platforms based on the 176 meteorological operational networks, the TIPEX-III network, the existing NIOST (Fig. 1a). Consistent with the operational observations of the 265 CMA, at each site the measurement system measures soil water content ( Fig. 1a). The regional network consists of 33 sites over 270 Naqu (Fig. 1c), which began operating in August 2015, and 17 sites over Shiquanhe This network consists of six additional sites at Bange, Namucuo, Anduo, Nierong, 280Jiali, and Biru, and contributes to integrated research on the high-resolution land-281 surface and PBL processes over the central TP and their effects on mesoscale systems. 282These observations have been conducted at Shiquanhe, Namucuo, Naqu, Anduo, Gongshan (98.67°E, 27.75°N) station on the southeastern slope of the TP (Fig. 1b), a 300 key area for gauging water-vapor transports from the Indian Ocean to East Asia. (Fig. 1b). A primary goal of these observations is to explore the cloud (Fig. 1b). A follow-up field campaign using ground-based radars Tuotuohe, Mangya, Golmud, and Xining meteorological stations (Fig. 1b). Using PRELIMINARY ACHIEVEMENTS OF TIPEX-III. 328The implementation of TIPEX-III has enhanced the monitoring capability for the 380(1) Cloud diurnal variation and warm rain process. 3...

The Microphysical Properties of Convective Precipitation Over the Tibetan Plateau by a Subkilometer Resolution Cloud‐Resolving Simulation

“…It is critical to cold‐rain microphysical processes. Additionally, with the airborne measurements from the cloud particle images and two‐dimensional stereo, Zhao et al () also confirmed that the dominant cloud particles in precipitating cumulus clouds over the Naqu area at temperatures of −2.5 to −3.5°C are supercooled water and a small number of ice particles. The maximum mixing ratio of ice crystals is only ~0.015 g kg −1 at near 13 km, and the amount of ice crystals is an order of magnitude smaller than that of cloud droplets.…”

Estimation of Surface Heat Fluxes Over the Central Tibetan Plateau using the Maximum Entropy Production Model

“…Their results showed that the monthly mean values of SH are between 60 and 80 W/m 2 over the central TP during July–August. This may be associated with the large surface turbulent exchange coefficients of the bulk transfer models used in their studies (Zhao et al, ). The regional mean values of LE MEP are generally greater than those of LE EC over the central TP, with the positive values of mean bias error (MBE) (Figures 4a2–e2) which is consistent with the previous results (e.g., Barr et al, ; Dugas et al, ; McNeil & Shuttleworth, ; Sellers & Hall et al, ; Twine et al, ).…”

“…Table shows the geographical conditions of the five TIPEX‐III experimental sites over central TP in detail. Each site has one planetary boundary layer tower (Zhao et al, ). Integrated sonic turbulent wind and CO 2 /H 2 O flux measuring instruments (made by Campbell Scientific, USA) with one 3‐D sonic anemometer and one CO 2 /H 2 O open‐path gas analyzer for wind speed (with an accuracy of 8.0 cm/s for horizontal velocity and 4.0 cm/s for vertical velocity), temperature (with an accuracy of 0.15 °C when temperature is 30 to 50 °C), and CO 2 /H 2 O flux (with accuracy of 0.2 mg/m 3 and 0.004 g/m 3 , respectively) are mounted at 2.98, 2.1, 2, 2, and 3 m at the five sites, respectively.…”

Development and Evaluation of an Ensemble‐Based Data Assimilation System for Regional Reanalysis Over the Tibetan Plateau and Surrounding Regions

“…Several major field campaigns (Ma et al, ; Zhang et al, ) aimed at deepening our understanding of atmospheric processes over the TP have been performed since 1979 (Tao et al, ). These include the ongoing Third Tibetan Plateau Atmospheric Scientific Experiment (TIPEX‐III) that was initiated formally in 2013 (Zhao et al, ). However, observational data sets from field campaigns are limited by their sparse spatial and temporal coverage, in particular at the climatic timescales.…”