25 May 1989, Volume 10 Issue 2

    

• Select all
  |

• Select
  A Preliminary Study on the Relationship Between Summer Temperature Drop and Mean Annual Temperature Drop During Ice Ages

  Zhou Shangzhe

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 95-104. https://doi.org/10.7522/j.issn.1000-0240.1988.0014

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  It is very important to study summer temperature during Quaternary ice-ages for reconstructing ancient enviroments. In this paper, the auther carried out a deduction on the relationship between the summer temperature drop and mean annual temperature drop during ice-ages based on the change of natural zone. The result shows that the value of summer temperature drop was lower than that of mean annual temperature drop according to the range of horizontal change of natual zone longitudinally; on the contrary, the value of summer temperature drop was higher than that of mean annual temperature drop in terms of the vert-tical change of the mountain natural zone. Because of this reason, it is believed that the relation between the two drops is dependent on the cause of ice-age. Recently the Milankovitch theory is eulogized as the most up to date solutions to the ice-age cycle. Therefore the influence of the change of obliquity ε to summer temperature and mean annual temperature is discussed in this paper and it is found that the change of ε is a element that makes summer tern- perature change and does makes mean annual temperature change.The auther thinks that although the study of the horizontal and veritical ranges of natural zone variations are the main methodes of reconstructing ancient temperature (including summer temperature and mean annual temperature). We can not make use of it and must pay attention to ice-age theoretical study.
• Select
  Cryosphere Fluctuation in the Past Century

  Li Peiji

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 105-116. https://doi.org/10.7522/j.issn.1000-0240.1988.0015

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The rising concentration of CO₂ and other greenhouse in the atmosphere is likely to produce a warmer climate in the past century as well as in the future. In fact, it is this twentieth century warming that terminated the Litte Ice Age and did indeed lead to a general retreat of glaciers. Lone term monitoring on cryosphere as well as empirical and theoretical studies concerning the response of the earths snow and ice to a global temperature increase revealed that the CO₂-induced climate change might exist profound effect on cryosphere.Observed long-term change in glacier volume, and annual mass balance models yield the data on thetransfer of water from glacier to the ocean. The glaciers and small ice caps of the world have in general been shrinking since the turn of the century. Shrinkage has been most pronounced among temperate and mid-latitude glacier. The wastage of the world’s glaciers and small icecaps contributed 0.46 ± 0.26mm/yr. to the 61-yr rise in sea level, which represents between 1/4-1/2 of the observed sea level rise.The estimates of the mass balance of the Greenland ice sheet by the hydrological budget methodsuggest that it is not greatly out of balance with the present climate. Observation of present elevation changes of the ice sheet surface indicates thining of the marginal zones and thickening of the central partThe present-day net balance estimates of the Antarctic ice sheet suggest growth, ranging about-20% to +50% from a balance state. But it may begin to retreat from bottom due to increased bottom melting which would probably cause grounding lines to retreat and would be accompanied by thinning and accelerated discharge from the inland in ice sheet A drastic retreat of west antarctic sheet in some day would cause mean global sea level to rise by as much as 5- 6 m and this would have far-hing consequences.The CO₂-induced changes in sea ice could have major climatic significance. The arctic ocean iceextent retreated by 10% from the 1935-1960- And a 4℃ summer warming would elminate the summer packice completely. The extent of antarctic pack ice in the summer as charted from satellite imagery, decreased by 2.5×10⁶km² between 1973 and 1980. The U. S. Navy and Russian atlases and whaling and research ship reports from the 1930’s indicate that summer ice conditions earlier in this century were heavier than the current average. Decrease in snow cover extent is anticipated in response to CO₂-induced global warming. Many of the CO₂-related changes in snow cover is and will be in middle latitudes and their effects are expected to be localized. However, there is evidence of increased snowfall amount with higher winter temperatures in some high-latitude regions. The climate model simulations have shown an increase in the snowpack in high-altitude locations, particularly in Antarctica, and a considerable desiccation of the soiliin the mid-latitude agriculturally-productive areas in the Northern Hemisphere. This spring dryingoccurred in part due to the earlier melting of the seasonal snowpack in the CO₂-enriched world the snow resource fluctuation in China is positively correlated with the global mean temperature. It increases during the warming period and decreases during the cooling period. The heavier snow winters appear to be associated with the EL Nino/Southern Oscillation.
• Select
  The Cycles and Periods of the Quaternary Climate Change

  Zhao Jingbo

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 117-124. https://doi.org/10.7522/j.issn.1000-0240.1988.0016

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  We have found 40 paleosoil layers which occur not only in the loess of the middle Pleistocene, but also in the loess of the early pleistocene at the Shuijiazhui loess section,Lantian, Xian. According to the loess and paleosoil in the section, 25 climate cycles nearby Xian can be divided since loessdeposition. The 25 cycles were not local climate events restricted in Xian region. Climate change indicated by loess and paleosoil in Luochuan, Shanxi. is similar to that in xian region. 24 cycles have been determined in the light of CaCO₃ contents and sporo-pollen materials in river-lake deposits in Hebei plain, since 2430000 Y. B. D. By the age dating in magnetism, we conclude that the basic cycle of the Quaternary climate change is about one hundred thousand years.At present, there are two kinds of completelty different methods of dividing the Quaternary climate in the world. The main difference of the two methods is not due to inconsist ency of climate change, but to the different areas, sections and climate marks in study that are not identical in sensitivity to climate changes.The division at four, five or six glacial periods and interglacial preiods on the basis of the glacial till and glacial eroson landform is not entire. But there is little difference in the number of glacial periods and interglacial periods in many areas in the world,and there are4-6 coldresistant vegtation periods, corresponding toglacial periods in the glacial regions, indicated by sporo-pollen materials in the areas where the Quaternary glacier did not occur, there fore we infer that there were four, five or six periods in the Quaternary in which the climate change range was greater than other periods.
• Select
  Some Characteristics of the Climatic Landform in the Northeast China Since the Last Glacial Epoch

  Xiao Ronghuan, Hu Jianbin

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 125-134. https://doi.org/10.7522/j.issn.1000-0240.1988.0017

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  In the last glacial epoch, many cirques with the height of about 2200m above sea-level developed around the Tianchi Lake of the Changbai Mountains. Vast areas of the Northeast were in the periglacial environment. Up to now, many periglacial forms are still dominant in geomorphologic landscape. During the post-glacial period, glacial geomorphology of the Changbai Mountain was transformed by the periglacial environment, and periglacial geomorphology in vast areas was transformed by the warmer environment. The Ice-snow Line, as a boundary of the climatic landform, moved northward form 44-45°N of the last glacial stage to 51°N of the Present situation. Since the last glacial stage, the climatic landscape zones have shown the characteristics of moving parallelly along longitude and latitude.
• Select
  Solar Penetration Radiation in Snow Layers

  Xie Yingqin, Zang Jinsen

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 135-142. https://doi.org/10.7522/j.issn.1000-0240.1988.0018

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The distribution of solar radiation energy in a snow layer depends on the Lambert’s law. In granular snow layers the absolute value of the absorption coefficient varies form 0.297 to 0.457cm^-1 for the shortwave radiation in the wavelength range between o.4and 1.1 μ.Various extinction observations indicate that the absorption coefficient depends on the wavelength, snow depth and the incident radiation intensity. In addition, about 86% of the shortwave incident radiation is absorbed by the snow layer from surface to the depth of 5 cm, and only about 14% of that can penetrate into the deeper snow layers. The effective depth of penetration is about 20cm.
• Select
  Effects of permafrost on Ground water in Huola Basin, Northern Daxinganling Ridge

  Wang Baolai, Zhou Youwu, Guo Dongxin

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 143-150. https://doi.org/10.7522/j.issn.1000-0240.1988.0019

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Permafrost, as, an impermeable frost-seam, increases the artesian pressure and depth of groundwa-ter. The seam lies below the permafros layer. The recharge and discharge of groundwater are conducted mainly through taliks and shattered fault zones. Existence of taliks with a large area can increase the exchange intensity of groundwater and lower mineralization of groundwater.
• Select
  A Primary Calculation of Temperature and precipitation in Tianshan Mountains, China

  Liu Chaohai, Ding Liangfu

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 151-159. https://doi.org/10.7522/j.issn.1000-0240.1988.0020

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Using the meteorological data of the meteorological stations and hydrological stations in Tianshan Mountains, and the new data of the glacier inventory in Tianshan,the authors computed the mean summer (6-7) temperature at the typical altitudes, and estab-lishec the empiric formula calculatin the annual ablation (A) at the equilibrium line altitude (ELA): A = 0.78(T_6-8 +9.0)^3.09. The annual precipitation near ELAs in every ranges of Tianshan Mountains was calculated by extropolation. The results show that the maximum precipitation in Tianshan Mountains appears to be in the south slope of Awulale Range and the north slope of Nalati Range with an annual precipitation value of 1000-1100mm. The minimum precipitation is in the South Range of Tianshan, north slope of Tianger Range and the south slope of Nalati Range.Using the data of the glacier inventory and the meteorological data in Tianshan Mountains, the authors discussed the climatic conditions of the development of the glaciers in Tianshan Mountains, the relationship between the characteristics of the glacier distribution and the climatic condition, the reason that the numbers of the glaciers are larger in the south slope than in the north slope in part range of Tianshan Mountains, and finally discussed the distribution characteristics of the ice formation zones of the glaciers.
• Select
  Climatic Geomorphology of the Anyemaqen Mountains

  Wang Jingtai

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 161-171. https://doi.org/10.7522/j.issn.1000-0240.1988.0021

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The glaciers of the Anyemaqen Mountains include those of valley, cirque and hanging types, as well as one small ice cap. They are of sub-continental type. The surrounding nivation zone is very extensive, below which lies a vegetated periglacial zone.Solifluction lobes are well developed as are the relict thermokarst forms. Below 4000m a.s.l. seasonal erosion by flowing water is widespread and there is a dense bush vegetation with some trees.The climatic landform zonation in the Anyemaqen region is a result of the long-term evolution. Current geomorphological processes have led to a distinct vertical zonality controlled in response to changes in climate with altitude. The slope forms clearly represent a gradational series. Each of these processes occurred within different height zones in the past. The steep bedrock slopes formed by glacial erosion during the last Quaternary glaci-ation have been replaced by the debris and solifluction slopes of the present regime resulting from climatic amelioration and deglaciaciation. The lower limit of the periglacial zone during the last glaciation may have reached 3800 m a.s.l. or even lower, as seen from the evidence of the distribution of former glaciers. glaciers. However, typical periglacialslopes are now hard to find in these areas, owing to the erosion by slopewashes and related processes.The last glaciation ended only about 10,000 years ago. Although the morphological framework imposed by glacial erosion still exists, the essential slope forms have been greatly changed. This is a measure of the role of the climate in the current morphogenesis to which must be added the active role played by neotectonics in the uplift of the Qinghai-Xizang plateau.
• Select
  The Relation Between the Growth of Seasonal Depth Hoar and the Avalanches in China

  Wang Yanlong

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 173-180. https://doi.org/10.7522/j.issn.1000-0240.1988.0022

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The growing processes of depth hoar under the maritime and continental climatic conditions are discussed in particular and it is found that in western China there are four developing stages of depth hoar, i.e. embrynic, loose, aggregate and melt-freeze stage. The temporal and spatial distribution of depth hoar is quite different for different area because of the climate. The depth hoar developed under continental climatic condition has the longest existing time and the largest thickness, maybe more than 85% of total depth of snow cover. But the thickness of depth hoar developed under maritime climatic condition does not more than 25% of total depth of snow cover. So the depth hoar developed under different climatic condition contributes to the occurence of avalanche differently owing to the difference in depth, density and strength of snow cover. A depth hoar well developed under mantime climatic condition is a signal showing an avalanche with large-scale and wide range will happen. But under continental climatic condition, even if the depth hoar should reach 50-60cm, more than 60% of to tal depth of snow cover, avalanche wouldn’t occur, and then there is a possible avalanche damage only. A depth hoar avalanche can not occur because of minor depth and density of snow cover, though the depth hoar has been well developed under continental climatic condition. Finally, the developing feature of depth hoar avalanche is discussed.
• Select
  Fluctuations of Glaciers on the Northwest Slope of Mt. Nanjagbarwa Since the Last Glaciation

  Zhang Zhenshuan

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 181-188. https://doi.org/10.7522/j.issn.1000-0240.1988.0023

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  This section deals with the till stratigraphy, glacial evolution and relationships between glacier variation and climate in the Mt. Nanjabarwa region and some results have been achieved:1. There were three fluctuations of glaciers since the late Pleistocene in this region, that is the last glaciation with the age of 25000-10000B.P. during the late Pleistocene, the Neoglaciation with the age of 3500-1000 B.P. during the late Holocene, and the Little Ice Age with the age 400-200 B.P. also in the late Holocene.2. In the above periods, there are clear till stratigraphies and obvious glacial evolation processed. The area of glaciers decreased, the length shortened and the snow line rose gradually since the last glaciation. The climatical fluctuations were in step with those of the glaciers.
• Select
  Development of Apparatus Used for Water Migration Test in Soil

  Xu Xiaozu, Wang Jiacheng, Deng Yousen

  JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 1988, 10(2): 189-196. https://doi.org/10.7522/j.issn.1000-0240.1988.0024

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The apparatus used for the test of water migration in soil mainly consists of three parts a refrigerated recirculating bath, a thermotank and a soil container. The refrigerated reci-rculating bath consists of a compressor system, a main cooler and two subcoolers. The evaporator is fixed in the main cooler. The cooling liquid can be circulated from the main cooler to the tubes in the two subcoolers and in the thermotank by a pump.Temperatures in the two subcoolers and in the thermotank are controlled by temperature controllers with the thermostability in the range of ±0.1℃. The refrigerated recirculating bath can provide different temperatures at both ends of the soil container at the same time. The thermotank consists of a cooling tube, a electric heater and a fan. It keeps the temperature in the thermotank stable within the range of ±0.5℃, even if the ambient temperature is fluctuated in a range of 10℃ instantaneously. The size and the structure of the soil container is similar to one suggested by American scientists (1983) in order to make the test data comparable. The soil container consists of a top plate, a bottom plate and a plexiglass tube cut into halfs. The structure of the two plates is suitable for the circulation cooling liquid and supply of water. The apparatus has the following features: 1) All spare parts are homemade. 2) One compressor system provides two different temperatures at the same time. 3) The apparatus is suitable for different test conditions such as different overburden pressures, temperature gradients, water supply. and so on. The apparatus can be used for the studies of water migration, frost heaving and the formation of the cryogenetic stucture of soil.