1. The 5th TPE workshop Berlin, 8-9 Dec. 2014 The increasing dustiness in Tibetan Plateau ice cores over the past decades under warming perspective Guangjian Wu, Tandong Yao, Baiqing Xu, Chenglong Zhang, et al. wugj@itpcas.ac.cn Institute of Tibetan Plateau Research, Chinese Academy of Sciences Institute of Tibetan Plateau Research, CAS

2. 1951–2012: 0.12 °C per decade Institute of Tibetan Plateau Research, CAS 2 The dust trend under warming -20~-60%

3. Also increasing dust loadings? Institute of Tibetan Plateau Research, CAS 3

4. 4 The Antarctic and North America Nature Geoscience 2008

5. 5 Dust trend and its impact on the Tibetan Plateau Institute of Tibetan Plateau Research, CAS Impacts of dust on snow and glaciers:  decrease snow albedo and induce enhanced melting  change the duration of snow cover  affect the glacier-fed rivers and water resource

6. 6 Taklimakan Central Asia Africa Arab Thar  Adjacent to and largely surrounded by Asian deserts  Located at the downwind (Westerlies) of arid regions  Deposited and preserved in glaciers Westerlies

7. 7 Aerosol Optical Depth over and around the Tibetan Plateau and ice core drilling Institute of Tibetan Plateau Research, CAS Tanggula Zuoqiupu

8. Udaoliang Tanggula ice core (5743m asl, 33 m thick) Shenza Taklimakan Dating the Tanggula ice core (back to 1850 AD) 8 Institute of Tibetan Plateau Research, CAS

9. Zuoqiupu (5565 m asl, 116m long) Shenza Zedang Ng Ali 9 Dating the Zuoqiupu ice core (back to 1935 AD) Institute of Tibetan Plateau Research, CAS

10. Two dusty stages: 1860-1874: high flux coarse grain size 1930-1954: relatively low flux coarse grain size cold-dusty pattern significant (α=0.01) increase Since 1960: moderate flux moderate grain size warm-dusty pattern 10 Annual average of Tanggula ice core record Institute of Tibetan Plateau Research, CAS

11. 11 Annual average of Zuoqiupu ice core record  Dust particles became fine since 1965  Dust conc. kept on increasing, became much higher since 1980  Warming since 1965 Institute of Tibetan Plateau Research, CAS

12. Dataset: ECMWF ERA-40 Composite analysis on: over and near the Tibetan Plateau  200 hPa zonal wind (high-level Westerlies)(unit: m s −1 )  500 hPa height (unit: m) six extremely high dust flux years vs. eight extremely low dust flux years (after the 1954 horizon) 12 Possible circulation mechanism for high dust Institute of Tibetan Plateau Research, CAS

13. 13 Tanggula: 200 hPa zonal wind strength anomaly during high dust years, high-level Westerlies over the Tibetan Plateau strengthened positivenegative 95% confidence Institute of Tibetan Plateau Research, CAS

14. 14 Tanggula: 500 hPa height anomaly positivenegative 95% confidence During the dusty years, a negative anomaly was found over the upwind dust source regions (Tarim Basin and western Tibetan Plateau). The low pressure (cyclone) activities favor dust storm events Institute of Tibetan Plateau Research, CAS

15. 15 Zuoqiupu: 850-1000 hPa height anomaly positivenegative 95% confidence Institute of Tibetan Plateau Research, CAS

16. 16 Eolian dust activities seem to be active on Tibetan Plateau Shen et al., GPC 2010 Institute of Tibetan Plateau Research, CAS Eolian sand deposition along Yarluzangbo valley

17. Telegraph poles and wires buried by dune at Xidatan, south of Golmud Modern dunes along the Qinghai-Tibet Highway 17 Institute of Tibetan Plateau Research, CAS

18. 18 Desertification in the central Tibetan Plateau area in the source region of Yangtze R. increased by 2,678 km 2 (+8.8%) Institute of Tibetan Plateau Research, CAS Desertification and active eolian dust on the Tibetan Plateau seems intensified over the past decades

19. 19 Summary  Along with warming, dustiness intensified since 1960s in the central and southeastern Tibetan Plateau  Possible warm-dusty type pattern in the central Tibetan Plateau within current warming perspective, while previously cold-dusty type  Possible circulation mechanisms for the increased dust: strengthened Westerlies; intensified low pressure activities in the upwind source regions Institute of Tibetan Plateau Research, CAS Future work  More dust records from the Third Pole region  Tracing the provenance of dust in snow/ice

20. Thank you for your attention!