vladimir aizen: climate and environmental change impact cryosphere/water resources central asia
DESCRIPTION
The central Asian cryosphere is a part of planet's climate and hydrological system, one that is particularly at risk from accelerated climate changes. Despite the very arid climate, the central Asian glaciers comprise approximately 10,000 km3 fresh water that is a vital source of life for more than 100 million people. The history of climate revealed from the ice-core isotope-chemistry records large variability in the past 12,600 years in central Asia. Glaciers in Altai and inner Tien Shan did not exist at the end of Pleistocene, and were regenerated during and the Younger Dryas, when air temperature was 6.1 ± 0.3◦C lower than the modern mean air temperature (Aizen et al, 2013d). An abrupt increase in air temperature of more than 6.7°C at the end of the Younger Dryas occurred for less than one century did not destroyed glaciers in Altai. During the last 30 years of modern time....TRANSCRIPT
1
Modern and past climate and environmental change impact on cryosphere/water resources in Central Asia
Vladimir B. Aizen and Elena M. Aizen University of Idaho, USA E-‐mail: [email protected]
Abstract
The central Asian cryosphere is a part of planet's climate and hydrological system, one that is particularly at risk from accelerated climate changes. Despite the very arid climate, the central Asian glaciers comprise approximately 10,000 km3 fresh water that is a vital source of life for more than 100 million people. The history of climate revealed from the ice-‐core isotope-‐chemistry records large variability in the past 12,600 years in central Asia. Glaciers in Altai and inner Tien Shan did not exist at the end of Pleistocene, and were regenerated during and the Younger Dryas, when air temperature was 6.1 ± 0.3◦C lower than the modern mean air temperature (Aizen et al, 2013d). An abrupt increase in air temperature of more than 6.7°C at the end of the Younger Dryas occurred for less than one century did not destroyed glaciers in Altai. During the last 30 years of modern time, annual air temperature increased 0.65°C, mainly in summer, and up to 1.6°C over the prairies and deserts. In high mountains of central Tien Shan air temperature increased on 0.21°C but, even a small increase of summer air temperatures intensifies seasonal snow and glacier melt, decreasing snow cover duration for one month. The glaciers lost on average 14% of area and 27% of volume in Altai from 1960s to 2009, 8.5% of area in Tien Shan and 5% in Pamir from 1970th to 2009.
Keywords: Central Asia; cryosphere, climate, snow cover; glaciers; paleoclimate
Introduction Shrinking of alpine glaciers and the acceleration of the glacier’s recession appears from the
middle of 1970 in the majority of mountain regions of the World (Heiberly, 1990; Kadota et al., 1997; Liu et al., 2002; Zemp et al., 2006; Aizen et al., 2006; Niederer et al., 2008; Paul and Andreassen, 2009; Shahgedanova et al., 2010). An accurate evaluation of cryospheric changes becomes a crucial issue for water resource, water supply and hydropower assessments in central Asia. Central Asia has extremely fragile arid lowlands and water-‐rich highlands, where melt of glacier and seasonal snow cover supplies over 80% of river runoff (Dikih, 1993; Aizen, et al., 1998; Shi, et al., 2007). During droughts, glacial runoff can reach 45% (Schultc, 1965, Aizen, 1997). There is a lack of generalized knowledge on cryospheric changes over high central Asia. Existent investigations used data from a few stations (Table 1a), accounting for a relatively limited number of glaciers (Table 1b), which results often do not account for the extended terrain in central Asia and are valid only for local purposes.
Central Asia (Fig. 1) with area of about 6.2 million km2 consists primarily of planes, with high mountains, reaching 7,000 m in the south and southeast. The highest point is Kongur in the eastern Pamir, of 7719 m, and the lowest point is the Turphan depression in eastern Tien
Glacial Flooding & Disaster Risk ManagementKnowledge Exchange and Field Training
July 11-24, 2013 in Huaraz, PeruHighMountains.org/workshop/peru-2013
2
Shan, of -‐154 m bsl. In our research, Central Asia is bordered by Caspian Sea, western Siberia and Altai mountains, the Mongolian steppes and the Gobi desert, and the Takla Mahan and Karakum deserts.
Data and Methods Meteorological data include monthly average air temperatures and sums of
precipitation from 251 stations spanning 35.28°-‐50.25°N and 50.4°-‐91.98°E and from -‐134 m bsl to 4169 m asl for two periods: 1942-‐1975 and 1976-‐2009. Sums of annual (Pan), winter (Pw) and summer (Ps) precipitation, means of annual (Tan) and summer (Ts) air temperatures, linear trends (α) for the two periods (1942-‐1975 and 1976-‐2009) and their differences (ΔT, ΔP) were calculated. The statistical significance was determined by T-‐test, F-‐test and non-‐parametric test (Wilks, 2011). We consider acceleration (a) through changes in linear trends for two periods: a = α1976-‐ 2009 – α1942-‐1975.
To generate continuous spatial fields for climatic characteristics, we used the Geographically Weighted Regression (GWR) method (Hofierka et al., 2002) interpolating temporal gaps (Fotheringham et al., 2002; Brunsdon et al., 2001). The lapse were estimated for each grid point based on data from closest stations. Input from a station is linearly weighted due to its distance from the point. Cross validation was used to evaluate the errors of spatial interpolation.
Remote sensing data: Snow covered area: A 8-‐day dataset was developed based on 1 km AVHRR and High
Resolution Picture Transmission (NOAA, 1998, 2007) via NOAA Stewardship System (http://www.class.ncdc.noaa.gov/) from 1976 to 2009 using SAPS (Khlopenkov and Trischenko, 2007). MODIS Terra daily and 8-‐day snow cover product (MOD10A1v5 and MOD10A2v5) was obtained from NSIDC (http://nsidc.org/data/modis/). Auxiliary data include Digital Elevation Model (500 m -‐ 1 km), snow survey data, and land cover information. Snow survey data obtained from NSIDC were used to validate snow identification in daily composite AVHRR. The Land Cover Classification data at 1 km resolution from AVHRR (Hansen et al., 1998, 2000) was obtained from University of Maryland (Zhou et al, 2013).
Glacier area/volume (1970th-‐2009) were completed in three central Asia glacier inventories (http://www.asiacryoweb.org) using declassified photographs from Corona and KH-‐9 Mapping Program, Landsat ETM+ and ASTER images, and ALOS/PRISM 2.5 m resolution (Surazakov & Aizen, 2010; Aizen, 2011). Volume of all Altai-‐Sayan glaciers was estimated using glacier area/volume relationships developed with in-‐situ radio echo-‐sounding measurements of 130 glaciers (Nikitin, 2009). Maps of the Fedchenko Gl., central Pamir, from 1928 and 1958 photogrammetric surveys and data of ice surface velocity, DEMs and ground penetrating radar measurements in 2009, were used to estimate glacier ice-‐volume changes from 1928 to 2009 (Lambrecht, et al, 2013).
12,600 years paleoclimatic isotope-‐chemistry records were obtained from two surface to bedrock ice-‐cores drilled in 2003 on the West Belukha Plateau (Siberian Altai at 4115 m; 171.3 m depth) and in 2007 on the Grigorieva Ice-‐cap (Inner Tien Shan at 4563 m; 87.46 m depth). Both ice-‐cores were processed and analyzed at University of Idaho, University of Maine (USA), National Institute for Polar Research and Research Institute for Humanity and Nature (Japan) dedicated laboratories at 2-‐3 cm resolution (Takeuchi et al, 2013; Aizen et al, 2013).
Stable isotope ratios (δ18O, δD) were determined via headspace equilibration using a Finnigan Delta Plus isotope mass spectrometer coupled with Finnigan's GasBench II. The analytical precision of δ18O and δD isotope ratios was ±0.05‰ and ±0.5‰. Major ion
3
analysis was via suppressed ion chromatography using a Dionex DX500 system. Ion concentration was determined at 0.01–0.07m resolution with minimum of 1 ppb. Radiocarbon analysis of the POC fraction was conducted at Laboratory of Radio and Environmental Chemistry at Paul Scherrer Institute (Switzerland) (Jenk et al. 2009; Sigl et al., 2009). Radiogenic (δ3H) isotope ratios were measured via liquid scintillation counting at National Institute of Polar Research and in the Idaho State University, USA. The dating was based on: δ3H and 14C marks; seasonal signal in stratigraphy and stable isotope distribution; multi-‐identification of layers including forest fires, Tunguska explosion, dust storm and significant volcanic eruptions. The numeric modeling of ice thickness aging presented in Raymond (1983) and implemented by Kaspari et al., (2008), Thompson et al., (1989, 2000), Yao and Yang (2004), Davis et al., (2005) was applied. Information on discrepancy of dating presented in (Aizen et al., 2013d).
Results and Discussion Changes in climatic characteristics (between 1976-‐2009 and 1942-‐1975). Air temperatures. Increases in annual means were observed at 93% and 7% of stations show no changes. The area-‐weighted difference in annual mean temperature throughout the central Asia was 0.65°C, with the most increase in the summer. The most significant differences in annual/summer means were observed in the Aral Caspian deserts and Kazakhstan steeps (ΔTa=1°C, ΔTs =1.6°C). The lowest difference was in the central Tien Shan, 0.21°C. Differences in annual means decreased with altitude from 0.72°C below 1,000 m to 0.31°C above 3,000 m, while the summer differences were significant throughout all regions and altitudes. Area weighted means of acceleration was positive (0.034°C yr-‐1) throughout regions and altitudes with the most acceleration in summer (0.024°C yr-‐1). The western and eastern Pamir regions in summer are exceptions. Precipitation increased significantly at 35%, decreased at 35%, and did not change at the remaining 30% of stations. In summer 46% of stations showed decreases and 20% showed increases. In winter, 47% stations showed increases, while only 16% showed decreases. Spatially interpolated ΔPan ranged from +27 mm in plain/desert to -‐101 mm in the inner and central Tien Shan. The total area weighted ΔPan was positive because the areas with increased precipitation exceeded the areas with decreased precipitation by 8%. Increases in annual precipitation were observed in western and eastern Pamir, western Aral-‐Caspian, northern Tien Shan foothills, southern Altai-‐Sayan mountains and eastern Tarim deserts (42% of central Asia area). An increase in winter precipitation was observed below 2,000 m, while winter precipitation decreased in eastern Pamir and Tien Shan above 2,000m. Annual differences on average decreased in alpine areas above 3,000 m. However, the western Pamir ΔPan had increases at all altitudes, while the western, inner and eastern Tien Shan had significant decreases over all altitudes. The greatest decrease in precipitation occurred during the summer especially at altitudes above 3,000 m in Tien Shan.
Changes in cryosphere: Seasonal snow cover (1976-‐ 2009). The Man-‐Kendall's test revealed negative trend in
snow covered area (SCA) with the rate of -‐0.31% yr-‐1 in western Pamir above 3,000 m, -‐0.41% yr-‐1 in eastern Pamir above 4,000 m, -‐0.35% yr-‐1 in western Tien Shan above 3,000 m and -‐0.31% yr-‐1 in inner Tien Shan above 3,000m, while Altai-‐Sayan shows increase of SCA by +0.25% yr-‐1 due to increase of winter precipitation. Maximum decrease of SCA is observed at the beginning of June. There is the negative trend of snow cover duration (SCD) over 3,000 m
4
of -‐0.80 day yr-‐1 in Pamir and -‐1.20 day yr-‐1 in Tien Shan. The SCD reduced by 30 by 2009 in central Asia.
The glaciers of Altai-‐Sayan. Counting the glaciers larger than 0.1 km2, there were 1,428 glaciers with area of 1,285 km2 by 2009. The glaciers lost on average 14% of area from 1960s to 2009 (Surazakov et al., 2007; Nikitin, 2009; Shahgedanova et al., 2010; Aizen, 2011a). The recession varied from 4% for valley glaciers to 16% for small cirque and piedmont glaciers. The number of glaciers have reduced by 7.5% that mainly attributed by small glaciers. Average glacier retreat was from -‐2 to -‐10m yr-‐1 with maximum of -‐45m yr-‐1. Overall glacier recession was accompanied by expansion of 5 glaciers in 1988 and 8 glaciers in 1993. The glaciers ice volume was 33.5 km3 in 2009 and 42.6 km3 in 1960 (Nikitin, 2009). Altai’s glaciers lost 9.1 km3 (27%).
The glaciers of Tien Shan had area 12,949.29 km2 (7,590 glaciers, 1,840 km3) in 2009 and 14,152.23 km2 in the 1970th, resulting in 8.5% loss. The largest absolute and relative glacier area loss occurred in the northern Tien Shan (361 km2, 14.3%), where sums of precipitation decreased above 3,000 m (-‐18.6 mm), and the summer air temperatures increased on 0.44°C. Similar large absolute recession occurred in the inner and central Tien Shan at higher than in the northern Tien Shan elevations: annual precipitation decreased -‐35 mm and summer air temperatures increased 0.71°C. The least absolute glacier recession occurred in the western Tien Shan where the mountains do not reach 4000 m, summer air temperatures increased only 0.23°C and precipitation decreased -‐13.4 mm. The eastern Tien Shan lost 196 km2 of glacier area (12%) (Li, 2006; Aizen, 2013c). The tongue of the largest Tien Shan glacier, Inylchek, (59 km long, 547 km2) retreated 700 m and area loss is -‐0.98 km2 (-‐0.3%) from 1943 to 2011.
The glaciers of Pamir cover 12,449 km2 in 1970th and 11,834 km2 in 2009 (Aizen et al , 2011c). The Pamir glaciers changed mainly due to shrinkage of small glaciers with area <0.5-‐ 2.0 km2, which numbers decreased from 456 in 1970s to 359 in 2009. The number of medium (2.1 – 10.0 km2) and large glaciers (over 100 km2) remains stable and their area shrunk less than 2%. The large central Pamir glaciers are the most stable due to high elevated location of accumulation areas and precipitation surplus in the last two decades. The rate glacier recession is: -‐11.5% and -‐7.6% in Hindukush and Vakhshan Ranges, southern Pamir; -‐4.9% in Gissaro-‐Alai; -‐0.7% and -‐1.5% in central Pamir, and -‐3.8% in eastern Pamir and total glaciers area shrunk 615 km2 (5%) from 1970 to 2009. According to Schetinnikov (1998), Pamir glacier area has shrunk 10.5% from 1950s to 1980. The Fedchenko Glacier, one of the world largest alpine glaciers (72 km long, 579 km2), has insignificantly retreated 755 m with area loss of -‐2.91 km2 (-‐0.5%) from 1958 to 2009 (Lambrecht, et al., 2013; Aizen, eat al., 2013a). However, the level of the glacier surface dropped -‐30 m at the altitude of terminus (2,896 m) with ice volume loss of about 4.3 km³ from 1958 to 2009. The historical photogrammetry surveys on the Fedchenko Gl. have revealed that glaciers in Pamir had the highest rate of recession from 1928 to 1958. In the 1960s and between 2000 and 2007, the area loss was insignificant (0.014 and 0.010 km²/yr respectively) (Lambrecht, et al, 2013).
Paleoclimate The Altai-‐Sayan and Tien Shan glaciers below 5,000 m did not exist in the Bølling-‐Allerød
period (Takeuchi, et al., 2012; Aizen, et al., 2013d). Altai-‐Sayan glaciers regenerated during the Younger Dryas (YD), when air temperatures were on average 6.1°C lower than in the Recent Warming Period (RWP), i.e. from 1993 to 2003. The inner Tien Shan Glaciers regenerated later (Takeuchi et al., 2013). An abrupt decrease in air temperatures at the beginning, and an increase at the end, of the YD intensified winds and dust loading to atmosphere from
5
expanded Asian deserts. Concentrations of major ions increased significantly during the transitional time of abrupt air temperature change while during the minimum air temperatures of the YD, mineral dust loading weakened. These results are in accordance with analyses from Greenland (Mayewski et al., 1997), Antarctica (Jouzel et al., 1996), and tropical alpine (Thompson et al., 1995) ice cores. After the YD, major ions concentration decreased, with the lowest concentrations during RWP.
During the Holocene, the time colder than RWP observed for about six and a half millennia, i.e., YD, Pre Boreal Oscillation, Severe Centennial Drought (SCD). During SCD air temperature was on average 4.9°C lower than during the following MWP, and 4.41° lower compared to the recent time. The Altai glaciers survived the Abrupt Warming Events, the Holocene Climate Optimum (HCO), and the Medieval Warm Period (MWP). Air temperatures during the HCO and MWP were warmer corresponding to a 1.6°C and 2.4°C centennial means increase compared RWP. During the MWP, decadal means exceeded 3.3°C the recent decadal mean air temperatures. The most intensive enrichment of δ18O is related to circa 760 AD during the MWP when temperatures reached a maximum, further cooling followed gradually with periods of higher or lower temperatures until the middle of 20th century.
Changed trajectories in prevailing western and northwestern storms from the Atlantic during MWP described by Bradley (2000), Bradley et al. (2003), resulted in increase share of re-‐evaporated moisture from the Aralo-‐Caspian basin, which extended and dominated as far as Tien Shan and Siberia with a maximum share during the pre-‐industrialization time (Aizen et al., 2013d).
Conclusion Significant increases in annual and summer average air temperatures for the last 30 years
were observed at 93% of central Asian stations. The most significant increase was observed in the Aral Caspian deserts and Kazakhstan steeps. Acceleration in grow of annual and summer air temperatures were positive throughout regions and altitudes, except for the western and eastern Pamir in summer. Increases in precipitation for the last 30 years were observed in the western Pamir, the western Aral-‐Caspian, the northern Tien Shan foothills, Altai-‐Sayan mountains and eastern Tarim deserts. The increase in winter precipitation was observed mainly below 2,000 m, and in central Pamir and eastern Pamir above 5,000 m. The largest decrease in precipitation observed during the summer, particularly in Tien Shan over 3,000 m asl.
The rate of seasonal snow covered area decrease for the last 30 years varied from -‐0.31% to 0.41% yr-‐1 in western and eastern Pamir, and in western and inner Tien Shan above 3,000 -‐4,000 m. The Altai-‐Sayan shows positive rate: +0.25% yr-‐1.
The rate of glacier area change is different in the large glacierized massifs and small glaciers. The biggest glacier recession observed below 4,000-‐4,500 m. The 80% of glacier covered area are presented by several large glacierized massifs over 300 km2 each with accumulation areas above 5,000 m, where the rate of area recession does not exceed 3% for the last 40-‐60 years. However, changes in glacier covered area do not represent the real changes of glaciers. To estimate the water resources in central Asia, assessment of changes in ice volume is necessary.
Glaciers up to 5,000 m in central Asia did not exist during the Bølling-‐Allerød interstadial period. The climate that time was warmer than during the last 30 years. The glaciers regenerated during and after the Younger Dryas, when air temperatures were on average 6.1oC lower than now. At the end of Younger Dryas air temperature increased abruptly more than 6.7oC within 100 years. Reconstructed air temperatures shows several periods during the
6
Holocene Climate Optimum (7,000 to 3,600 cal yrs BC) and Medieval Warm Period (AD 700–1,150) with air temperatures up to 3.3oC higher than in the last 30 years decadal mean. References Aizen, V.B., H. Zhou, E.M. Aizen, C. Mayer, A.B. Surazakov. Central Pamir Glaciers regime and
dynamics: 1928-‐2011 photogrammetry, GPS survey, Corona KH-‐9, Landasat, SRTM, ALOS PRISM data (2013a, in process).
Aizen, E.M., V.B. Aizen, H. Zhou. Atmosphere Circulation Patterns and Climate Changes in Central Asia. Journal of Climate (2013b, submitted).
Aizen, V. B., E.M. Aizen, A. B. Surazakov, S.A. Nikitin, J. Kubota, H. Zhou. Glaciers changes in Tien Shan in 20th century J. Glaciology (2013c, submitted)
Aizen, E.M., Aizen, V. B., Takeuchi, N., Joswiak, D. R., Fujita, K., Nikitin, S. A., Grigholm, B., Zapf, A., Mayewski, P.A., Scwikowski, M., Nakawo, M., Abrupt and moderate climate changes at high-‐mid latitudes of Asia during the Holocene. Submitted to the Journal of Glaciology (2013d, in review))
Aizen, V.B. 2011a. Altai Glaciers. Encyclopedia of Snow, Ice and Glaciers. Ed: V.P.Sigh, Springer Publisher, p.1253.
Aizen, V.B. 2011b. Tien Shan Glaciers. Encyclopedia of Snow, Ice and Glaciers. Ed: V.P.Sigh, Springer Publisher, p.1253.
Aizen, V.B. 2011c. Pamir Glaciers. Encyclopedia of Snow, Ice and Glaciers. Ed: V.P.Sigh, Springer Publisher, p.1253.
Aizen, V.B., P.A. Mayewski, E.M Aizen, D.R. Joswiak, S. Kaspari, S. Sneed, A.B. Surazakov, B. Grigholm, A. Finaev. 2009. Stable-‐Isotope and Chemical Time Series from Fedchenko Glacier Firn Core (Pamir).J. of Glaciology, V.55/190 pp.275-‐291.
Aizen, V.B., E.M. Aizen, A.B. Surazakov, V.A. Kuzmichenok, 2006. Assessment of Glacial Area and Volume Change in Tien Shan (Central Asia) During the Last 150 years Using Geodetic, Aerial Photo, ASTER and SRTM Data. Ann. Glac., V.43, pp. 202-‐213.
Aizen V. B., E. M. Aizen, J. Melack and J. Dozier, 1997. Climate and Hydrologic Changes in the Tien Shan, Central Asia. J. Climate, 10, 6, 1393-‐1404.
Aizen, V.B., E.M. Aizen, 1998. Estimation of glacial runoff to the Tarim River, Central Tien Shan. Proceedings of International Symposium "WaterHead'98", Merano, ITALY, IAHS Publ., No 248, pp.191-‐199.
Bradley, R.S., K.R. Briffa, J. Cole, M.K. Hughes and T.J. Osborn. 2003. The climate of the last millennium. In: Alverson, K., R.S. Bradley and T.F. Pedersen (eds.) Paleoclimate, Global Change and the Future. Springer, Verlag, Berlin, 105-‐141.
Bradley, R. 2000. 1000 Years of Climate Change, Science 288:1353-‐1354. Brunsdon, C., J. McClatchey, and D.J. Unwin, 2001. Spatial variations in the average rainfall-‐
altitude relationship in Great Britain: an approach using geographically weighted regression. International Journal of Climatology 21 (4), pp.455-‐466.
Claussen, M., C. Kubatzki, V. Brovkin, A. Ganopolski, P. Hoelzmann, and H.-‐J. Pachur. 1999. Simulation of an abrupt change in Saharan vegetation in the mid-‐Holocene. Geoph. Res. Lett., 26(14), 2037-‐2040.
Davis, M.E.., L.G. Thompson, T.Yao and N. Wang. 2005. Forcing of the Asian monsoon on the Tibetan Plateau: eveidence from high-‐resolution ice core and tropical coral records. J. Gephys. Res., 110 (D4), D04101, (10.1029/2004)D004933.)
Dikih, A. N., 1993: Glacial runoff of Tien Shan rivers and its role in formation of total runoff J. Data Glaciol. Studies, 78, pp. 5–43 (Russ).
7
Froehlich, K., J.J. Gibson and P. Aggarwal. 2002. Deuterium excess in precipitation and its climatological significance. In Study of environmental changes using isotope techniques. Vienna, International Atomic Energy Agency, C&S Papers Series 13/P, 54–65.
Fotheringham, S., M. Charlton, and C. Brunsdon, 2002. Geographically Weighted Regression: The Analysis of Spatially Varying Relationships Wiley, 282 p.
Gillespie, A.R., R.M. Burke, and A. Bayasgalan. 2001. Neoglaciation in Central Asia. Geological Society of America, Abstracts with Program, 33 (6), 442.
Haeberli, W., 1990. Glacier and permafrost signals of 20th-‐century warming. Annals of Glaciology, 14, pp. 99-‐101.
Hofierka J., Parajka J., Mitasova H., Mitas L., 2002. Modeling impact of terrain on precipitation using 3-‐D spatial interpolation. Transactions in GIS, 135-‐150.
Kääb, A., E. Berthier, C. Nuth, J. Gardelle, Y.Arnaud. 2012. Contrasting patters of early twenty-‐first-‐century glacier mass change in the Himalayas. Nature. 23 August 2012. Vol 488, issue 7412, pages 495-‐498, doi:10.1038/nature11324.
Kadota T., K. Fujita, K. Seko, R.B. Kayastha, Y. Ageta. 1997. Monitoring and prediction of shrinkage of a small glacier in the Nepal Himalaya. Ann. Glaciol., 24, 90-‐94.
Khlopenkov, K.V., Trishchenko, A.P., 2007. SPARC: New Cloud, Snow, and Cloud Shadow Detection Scheme for Historical 1-‐km AVHHR Data over Canada. Journal of Atmospheric and Oceanic Technology 24, 322-‐343.
Krenke, A., 1998. Former Soviet Union hydrological snow surveys, 1966-‐1996, Edited by NSIDC [WWW Document]. URL http://nsidc.org/data/g01170.html
Kropacek, J., Neckel, N. 2012. Towards a robust method for estimation of volume changes of Mountain glaciers from ICESat data. EGU General Assembly 2012, held 22-‐27 April, 2012 in Vienna, Austria., p.2849.
Latifovic, R., Trishchenko, A.P., Chen, J., Park, W.B., Khlopenkov, K.V., Fernandes, R., Pouliot, D., Ungureanu, C., Luo, Y., Wang, S., others, 2005. Generating historical AVHRR 1 km baseline satellite data records over Canada suitable for climate change studies. Canadian Journal of Remote Sensing 31, 324–346.
Lambrecht, A., C. Mayer, V. Aizen, D. Floricioiu, A. Surazakov. The Fedchenko glacier in the Pamir during eight decades. Journal of Glaciology (2013, in review).
Mayewski, P.A., L.D. Meeker, M.S. Twickler, S.I. Whitlow, Q. Yang, W.B. Lyons, M. Prentice. 1997. Major features and forcing of high-‐latitude northern hemisphere atmospheric circulation using a 110,000-‐year-‐long glaciochemical series. J. Geoph. Res. 102: 26345-‐26366.
Jenk TM, S. Szidat, M. Schwikowski, H.W.Gäggeler, S. Brütsch, L. Wacker, H.A.Synal, M.Saurer, 2006. Radiocarbon analysis in an Alpine ice core: record of anthropogenic and biogenic contributions to carbonaceous aerosols in the past (1650-‐1940). Atmos Chem Phys 6:5381-‐90.
Jouzel, J., C. Waelbroeck, B. Malaize, M. Bender, J.R. Petit, M. Stievenard, N.I. Barkov, J.M. Barnola, T. King, V. M. Kotlyakov, V. Lipenkov, C. Lorius, D.Raynaud, C. Ritz, and T . Sowers. 1996. Climatic interpretation of the recently extended Vostok ice records. Climate Dynamics 12, 513–21.
Kaspari. S.,R. L..Hooke, P.A.Mayewski, S.Kang, S.Hou and D. Qin.2007. Snow accumulation rate on Qomolangma (Mount Everest), Himalaya: synchroneity with sites across the Tibetan Plateau on 50-‐100 year timescales. J. Glaciol., 54, (185). 343-‐353.
Li B, Zhu A-‐X, Zhang Y, Pei T, Qin C., Zhou C., 2006. Glacier change over the past four decades in the middle Chinese Tien Shan. J. Glaciol. 52/178.
8
Liu Chaohai, Xie Zichu, Liu Shiyin, 2002. Study on the glaciers variation and its runoff responses in the arid region of Northwest China. Science in China (Series D), 42 (suppl.), pp. 55-‐62.
Niederer, P., V. Bilenko, N. Ershova, H. Hurni, S. Yerokhin, and D. Maselli, 2008. Tracing glacier wastage in the Northern Tien Shan (Kyrgyzstan/Central Asia) over the last 40 years. Climatic Change 86 (1):227-‐234.
Nikitin, S.A. 2009. Zakonomernosti respredeleniya lednikovyh ldov v Russkom Altae, ocenka ih zapasov i dinamiki (Pattern of distribution of ice in the Russian Altai glaciers, evaluation of its resources and dynamics). Materialy Glaciol.Issledovanii (Data of Glaciological Studies), V. 107, 87-‐96 (Russ).
Paul, F. and L.M. Andreassen, 2009. A new glacier inventory for the Svartisen region, Norway, from Landsat ETM+ data: challenges and change assessment. J. Glaciol., 55(192), 607–618.
Raymond, CF.1983. Deformation in the vicinity of ice divides J. Glaciol., 29 (103), 357-‐373. Savelieva, N. I., I. P. Semiletov, L. N. Vasilevskaya, and S. P. Pugach. 2000. A climate shift in
seasonal values of meteorological and hydrological parameters for northeastern Asia, Prog. Oceanogr., 47(2–4), 279–297.
Schetinnikov, A.S. 1998. Morfologiya i regime lednikov Pamiro-‐Alaya (Morphology and regime of the Pamir-‐Alai glaciers). CANIGMI Publisher, Tashkent, p.219.
Schultc, V.L., 1965. Book: Riki Srednei Azii (The Rivers of Central Asia). Hydrometeo Publisher, Leningrad, 691p. (Russ).
Sigl M, Jenk TM, Kellerhals T, Szidat S, Gäggeler HW, Wacker L, Synal HA, Boutron C, Barbante C, Gabrieli J, Schwikowski M. 2009. Towards radiocarbon dating of ice cores. J Glaciol 55(194):985-‐96.
Shahgedanova, M. G. Nosenko, T. Khromova, A. Muraveyev. 2010. Glacier shrinkage and climatic change in the Russian Altai from the mid-‐ 20th century: An assessment using remote sensing and PRECIS regional climate model. J. Geophysical Research, V. 115, D16107, doi:10.1029/2009JD012976
Shi, Yafeng, Yongping Shen, Ersi Kang, Dongliang Li, Yongjian Ding, Guowei Zhang and Ruji Hu 2007. Recent and Future Climate Change in Northwest China. Climatic Change, Vol. 80, Numbers 3-‐4, pp. 379-‐393.
Surazakov, A.B., V. B. Aizen, 2010. Positional accuracy evaluation of declassified Hexagon KH-‐9 mapping camera imagery. Photogrammetric Engineering & Remote Sensing, Vol.76, N 5, pp.603-‐608.
Surazakov, A.B., V. B. Aizen, S.A.Nikitin. 2007. Glacier Area and River Runoff Changes in the Head of Ob River Basins During the Last 50 Years. Environmental Research Letters, http://dx.doi.org/10.1088/1748-‐9326/2/4/045017.
Surazakov, A.B., Aizen V.B. 2006. Surazakov, A.B., V.B. Aizen. 2006. Estimating Volume Change of Mountain Glaciers Using SRTM and Map-‐Based Topographic Data: IEEE, Transaction of Geoscience and Remote Sensing, V. 44, №. 10, October 2006.
Takeuchi, N., K. Fujita, V. B. Aizen, C. Narama, Y. Yokoyama, S. Okamoto, K. Naoki, J. Kubota. 2012. The disappearance of glaciers in Central Asia at the end of Pleistocene revealed by an ice core drilled in the Tien Shan Mountains. Earth and Planetary Science (2013 in review)
Taylor, K.C., P. A. Mayewski, R.B. Alley, E.J. Brook, A.J. Gow, P.M. Grootes, D.A. Meese, E.S. Saltzman, J.P. Severinghaus, M.S. Twickler, J.W.C. White, S. Whitlow, G.A. Zielinski. 1997. The Holocene-‐Younger Dryas Transition Recorded at Summit, Greenland. Science, 278: 825-‐827.
9
Thompson L.G, E. Mosley-‐Thompson, M.E. Davis, P.N. Lin, K.A. Henderson, J. Cole-‐Dai, J.F. Bolzan, K.B. Liu. 1995. Late Glacial Stage and Holocene tropical ice core records from Huascara´n, Peru. Science 269: 47–50.
Thompson, L.G., E. Mosley-‐Thompson, M.E. Davis, J.F. , Bolzan, T.Yao, N. Gundestrup, X. Wu, L. Klein, and Z. Xie. 1989. 100,000 year climate record from Qinghai-‐Tibetan Plateau ice cores. Science, 246(4929), 474-‐477.
Thompson, L.G., T. Yao, E. Mosley-‐Thompson, M.E. Davis, K.A. Henderson, and P.N. Lin. 2000. A high-‐resolution millennial record of the south Asian monsoon from Himalayan ice cores. Science , 289 (5486): 1916-‐1919.
Yao, T. and M.Yang. 2004. Climatic changes over the last 400 years recorded in ice collected from the Guliya Ice Cap, Tibetan Plateau. In Cecil, L.D., J.R. Green and L.G. Thompson, eds. Earth paleoenvironments: records preserved in mid and low-‐ latitude glaciers. Dordecht, Kluwer, 163-‐180.
Zemp, M., W.Haeberli, M.Hoelzle, F. Paul, 2006. Alpine glaciers to disappear within decades? Geophysical Research Letters, Vol. 33, l13504, doi:10.1029/2006gl026319.
Zhou, H., Aizen, V. B., Aizen, E. M., Deriving long term snow cover extent dataset from AVHRR and MODIS data: central Asia case study, Remote Sensing of Environment (2013, accepted)
Table 1. Recent publications on Central Asia climate, glaciers and hydrological changes. (a)
Region, area n Peri
od Resolut.
Technique
Temperature
Precipitation Others
(1) Tien Shan 200to > 4000 m
110
1940-‐1991
month
Thiessen polygon spatial averaging
+0.01C /yr
+1.2 mm/yr < 2000m
Max snow thickness, duration:-‐10cm,-‐9 day/50yrs
(2) CA 35-‐50N 75-‐120E
32
1951-‐1990
summer month
REOFA SE Mongolia & N China negative trend
North TS summer precip shows decadal scale oscillation
(3) Tajikistan 800-‐4160 m
4
1930-‐1991
year
valleys:+2.2°C/60yrs; HE: +0.4°C/60 yrs
<1000 m: +0.25 mm/yr >2000 m: +5.37mm/yr
(4) CA -‐25 to 848 m 37 to 50N 50 to 85E
26
1891-‐1991
year
Multi-‐regression; spatial extrapolation
Steady positive trend
Less steady positive trend
(5) 68-‐3614 m 39.73-‐
21 1879 200
year Regression, DFA
+ 0.027 C yr-‐1
Warming did not occurring steadily. Three
10
45.77N 62.12-‐78.4 E
1 thrusts were identified : beginning 30th ; 50th 70th
(6) north China 9
1979–1999
month Negative trend
Droughts for 3 summers (1997-‐99)
(b) Region Perio
d Initial area, km2
Data, map/image geo-‐referencing error, method of glacier delineation for the First (F), Second (S) and Third (T) inventories
Area change, km2 (%)
(7) Akshiirak
1943-‐1977 424.7
F, S: 1:10,000 topographic maps compiled from aerial photography; horizontal errors < 2.5 m; manual digitizing with stereo interpretation of the aerial photographs.
-‐17.95 (-‐4.2)
(8) Akshiirak
1977-‐2001 406.8
F: 1:50,000 map (Kuzmichenok, 1990); manual digitizing of the scanned map. S: ASTER image; georeferencing errors were not reported; manual digitizing.
-‐93.6 (-‐23)
(9) Akshiirak
1977-‐2003 406.8
F: original glacier boundaries from Kuzmichenok (1990) S: ASTER image; image orthorectification error 9 m; manual digitizing with stereo interpretation of the 3N and 3B bands.
-‐35.15 (-‐8.6)
(10) Zailiyskiy Alatau
1955-‐1990 287.3
F: Glacier boundaries were transferred from aerial photographs to 1:25,000 map; errors of area estimation 5-‐7%. S: Aerial photographs, same methods as above; errors of area estimation 2-‐3%.
81.8 (-‐29)
(11) Zailiyskiy Alatau (6 valleys)
1979-‐1999
198.37
F: 1:100,000 topographic maps; nominal accuracy 20 m; manual digitizing S: Landsat ETM; errors of area estimation 2-‐3%; multispectral classification and manual editing.
-‐34.2 (-‐17.3)
(12) Sokoluk R. basin, Kirgizkiy range
1963-‐1986 31.7
F: 1:25,000 topographic maps; nominal accuracy 5 m; manual digitizing. S: KFA1000 space photograph; orthorectification error 15 m; manual digitizing.
-‐4.2 (-‐13.3)
1986-‐2000 27.5 T: Landsat ETM+; orthorectification error 10
m; 4/5 band ratio for glacier classification. -‐4.7 (-‐17.1)
(13) Glacier No. 1, Urumqi
1962-‐2003 1.94
F,S: topographic maps 1962, 1964, 1986, 1992, 1994, 2000 and 2001; errors were not reported; manual digitizing. -‐0.24 (-‐12.4)
(14) Terskey-‐
1971-‐2002 245 F: Corona (1.8 m resolution);
orthorectification error 30.0 m; manual -‐18 (-‐8)
11
Alatoo digitizing. S: Landsat ETM+; orthorectification error 25.7 m; multispectral classification.
(15) Aksu R. basin
1963-‐1999 1760 F: Topographic maps of 1:100,000 scale;
manual digitizing. S: Landsat TM and ETM; manual digitizing. Linear error of glacier boundary change 90 m. Only the glaciers with length change >90m were included in the study.
-‐58.6 (-‐3.3)
(15) Kaidu R. basin
1963-‐2000 333 -‐38.5 (-‐11.6)
(16) Southern Chinese Tien Shan
1960s-‐
1999
2093.8
F: Aerial photographs and S: Landsat TM images. Linear error of glacier boundary change 90 m. Only the glaciers with length change >90m were included in the study.
-‐96.3 (-‐4.6)
(1) Aizen et al., 1997; (2) Yatagai and Yasunari, 1994; (3) Finaev, 2005; (4) Konovalov,
2003; (5) Giese et al., 2007; (6) Xu, 2001; (7) Kuzmichenok, 1990; (8) Khromova et al., 2003; (9) Aizen, et al., 2007; (10) Vilesov and Uvarov, 2001; (11) Bolch, 2007; (12) Niederer et al., 2008; (13) Ye et al., 2005; (14) Narama et al., 2006; (15) Liu et al., 2002; (16) Ding et al., 2006.
Figures Fig. 1. The Central Asia study area
12