The correlations of the d18Omax in the shallow ice core from the Guliya ice cap on the Tibetan Plateau with the global sea surface temperatures (SST) and height at the 500 hPa over the Northern Hemisphere were analyze...The correlations of the d18Omax in the shallow ice core from the Guliya ice cap on the Tibetan Plateau with the global sea surface temperatures (SST) and height at the 500 hPa over the Northern Hemisphere were analyzed. The correlated regions on oceans that have a significant influence on the d18Omax in the Guliya ice core are all located in ocean currents, or convergent regions of currents. They are the eastern Equatorial Pacific, the Northern Pacific Current, the Hot Pool in the eastern Indian Ocean, the Mozambique Current, the Northern Atlantic Current, the Canary Current and the Atlantic Equatorial Current. The d18Omax in the Guliya ice core has negative correlations with the SST located in the lower latitudes, and positive correlations with the SST in the middle latitudes. The correlated areas at the 500 hPa that have a great impact on the d18Omax are located in the subtropical highs over the mid-low-latitude oceans and the long-wave trough area over Balkhash Lake, where there are marked negative correlations between the heights in those areas and the d18Omax. The influencing mechanism is displayed by the diversity of the vapor origins transported to the Guliya region. The strengths of the European ridge and the ridge over Baikal Lake have notable positive correlations with the d18Omax. The two systems indirectly influence the vapor transportation towards the Guliya region by the adjustment of long-wave trough and ridge.展开更多
The climatic and environmental variations since the Last Interglaciation are reconstructed based on the study of the upper 268 m of the 309-m-long Guliya ice core. Five stages can be distinguished since the Last Inter...The climatic and environmental variations since the Last Interglaciation are reconstructed based on the study of the upper 268 m of the 309-m-long Guliya ice core. Five stages can be distinguished since the Last Interglaciation from the δ18O record in the Guliya ice core: Stage 1 (Deglaciation), Stage 2 (the Last Glacial Maximum), Stage 3 (interstadial), Stage 4 (interstadial in the early glacial maximum) and Stage 5 (the Last Interglaciation). Stage 5 can be divided further into 5 substages; a, b, c, d, e. The δ18O record in the Guliya ice core indicates clearly the close correlation between the temperature variation on the Tibetan Plateau and the solar activities. The study indicates that the solar activity is a main forcing to the climatic variation on the Tibetan Plateau. Through a comparison of the ice core record in Guliya with that in the Greenland and the Antarctic, it can be found that the variation of large temperature variation events in different parts of the world is generally the same, but the variation amplitude of temperature is different.展开更多
Based on a comparative study of the Guliya ice core with the Greenland GRIP ice core, the abrupt climatic changes on the Tibetan Plateau during the Last Ice Age have been examined. The major stadial-interstadial event...Based on a comparative study of the Guliya ice core with the Greenland GRIP ice core, the abrupt climatic changes on the Tibetan Plateau during the Last Ice Age have been examined. The major stadial-interstadial events and 7 warm events (Brφrump, Odderade, Oerel, Glinde, Hengelo, Denekamp, BQlling) are consistent in the two ice cores. However, there are some unique features in the Guliya ice core records. The transition from warm to cold periods in the Guliya ice core is faster than that in the Greenland GRIP ice core. The magnitude of the climatic changes in the Guliya ice core is also larger than that in the Greenland GRIP ice core. Another significant feature of the Guliya ice core records is that there is a series of cycles of about 200 a from 18 to 35 kaBP. 22 warm events and 20 cold events with a fluctuation magnitude of 71 have been distinguished. The warm and cold events with a fluctuation magnitude within 3 ℃ are as high as 100. It is speculated that the abrupt climatic changes in different periods are caused by different driving forces. The abrupt climatic changes from stadial to interstadial are driven by insolation and are amplified by the snow cover on the Tibetan Plateau. The abrupt climatic changes on shorter time scales are the consequence of interaction between sun activity and the monsoon.展开更多
The high-resolution records of δ18O and snow accumulation variations from the Guliya ice core provide valuable data for research on climatic variations at a decadal resolution during the past 2000 years in China. Bas...The high-resolution records of δ18O and snow accumulation variations from the Guliya ice core provide valuable data for research on climatic variations at a decadal resolution during the past 2000 years in China. Based on the ice core data, five spells have been divided: the warm and wet period before 270 AD, the cold and dry period between 280 and 970 AD, the moderate and dry period between 970 and 1510 AD, the well-defined' Little Ice Age 'with drastic cold-warm fluctuations between 1510 and 1930 AD and the warming period since 1930 AD. According to the combination of temperature and precipitation, cold events (55 times) surpass warm ones (26 times) , and dry events (55 times) surpass wet ones (45 times) . Cold-wet events (14 times) are less than cold-dry ones (16 times) , while warm-wet events (10 times) are more than warm-dry ones (4 times) . If the difference of 2‰ in δ18O (corresponding to 3K in temperature) between two or three adjacent decades is taken as the criterion of it, the abrupt change has taken place 33 times or so since the 3rd century. Among them are four large ones, occurring in 250-280, 550-580, 1220-1260, and 1520-1560 AD respectively. Comparison of the ice core data with the latest comprehensive research results on historical documents of East China shows that the great climatic events appeared simultaneously or at the same age in the ice core record and in the documentary data, suggesting that consistences and similarities in climatic variation among different areas are far away from each other in the lower to mid-latitudes. However, there is a great difference between them during the Medieval Warm Period, which is conspicuous in the historical documents but not in the ice core. In addition, the first cold event of the Little Ice Age on East China was 60 years earlier than that of the Guliya Ice Cap, when the degree of cooling in West China is more intensive than that of East China. But the third cold event in East China lagged behind that in West China during the late 19th century. The 1820s cold event in both West and East China may be caused by the magnificent Tambora volcanic eruption in 1815.展开更多
Evidence for the '8.2 ka cold event' has been provided mostly from the circum-North Atlantic area. However, whether this cold event occurred in other places is a key to understanding its cause. Here, we provid...Evidence for the '8.2 ka cold event' has been provided mostly from the circum-North Atlantic area. However, whether this cold event occurred in other places is a key to understanding its cause. Here, we provide the evidence for the '8.2 ka cold event' from the Guliya ice core in the northwest Tibetan Plateau, and it was found that the peak cooling (-8.3-8.2 ka) in this ice core was about 7.8-10°C, which was larger than the cooling in the North Atlantic region. The primary causes for this episode were diminished solar activity and weakened thermohaline circulation. Moreover, another weak cold event, centered about 9.4 ka, was also recorded in the Guliya ice core record. These two cold events were concurrent with the ice-rafting episodes in the North Atlantic during the early Holocene, which implies that the millennial-scale climatic cyclicity might exist in the Tibetan Plateau as well as in the North Atlantic.展开更多
The past temperature and precipitation variations are recorded precisely and continuously in μ18O and glacial accumulation records in the Guliya ice core. Fight warm periods and seven cold periods can be distinguishe...The past temperature and precipitation variations are recorded precisely and continuously in μ18O and glacial accumulation records in the Guliya ice core. Fight warm periods and seven cold periods can be distinguished in the past 2000 a. Of the four most intensive cold periods, three are in the Little Ice Age and one in the 11th - 12th century. The variation of precipitation is relatively small compared with that of temperature. Five humid periods and four dry periods occurred in the past 2 000 a. The long-term variation of temperature is positively correlated with that of precipitation according to the Guliya ice core record, but the variation of precipitation lags behind the variation of temperature.展开更多
By the analyses of Guliya ice core on the Ti-betan Plateau, it was found that the calcium (Ca2+) origi-nated from the terrestrial source is the main cation of soluble aerosol and a good proxy of the atmospheric compon...By the analyses of Guliya ice core on the Ti-betan Plateau, it was found that the calcium (Ca2+) origi-nated from the terrestrial source is the main cation of soluble aerosol and a good proxy of the atmospheric component and environment in the mountain ice core located in the mid-low latitude arid regions. Evident variation of Ca2+ concentration has been found in the Guliya ice core since the Last Intergla-ciation with two relatively strong increase periods and two weak increase periods. These variations are generally related to climatic changes: high Ca2+ concentration periods coincide with cold periods and low Ca2+ concentration periods coin-cide with warm periods. However, Ca2+ concentration does not always decrease (increase) with climate warming (cool-ing). The magnitude and phase of Ca2+ concentration does not always match temperature either. The changes of at-mospheric circulation, land surface condition and atmos-pheric humidity might be important factors which influence Ca2+ concentration besides temperature.展开更多
Based on the study of oxygen isotope and mi-croparticle in the Guliya ice core, atmospheric dust and en-vironmental changes in the northwest Tibetan Plateau since the last interglacial were revealed. The microparticle...Based on the study of oxygen isotope and mi-croparticle in the Guliya ice core, atmospheric dust and en-vironmental changes in the northwest Tibetan Plateau since the last interglacial were revealed. The microparticle record indicates that low dust load on the Plateau in the interglacial. Particle concentration increased rapidly when the climate turned into the last glacial and reached the maximum during the MIS 4. In the Last Glacial Maximum, however, the en-hancement of microparticle concentration was slight, differ-ing to those in the Antarctic and Greenland. On the orbital timescale, both the temperature on the Tibetan Plateau and summer solar insolation in the Northern Hemisphere had their impact on the microparticle record, but the difference in phase and amplitude also existed. Though having the same dust source, microparticle records in the ice cores on the Tibetan Plateau and the Greenland seem to have different significance.展开更多
The variations of NO\+-\-3 concentration in the Guliya ice core are reconstructed for recent about 1 000 a. Spectrum analysis of NO\+-\-3 indicates significant periodicities in the variations of NO\+-\-3 concentration...The variations of NO\+-\-3 concentration in the Guliya ice core are reconstructed for recent about 1 000 a. Spectrum analysis of NO\+-\-3 indicates significant periodicities in the variations of NO\+-\-3 concentration, which coincide with the periodicities of the solar activity. Therefore, a positive correlation between the variations of NO\+-\-3 concentration and the solar activity is found.展开更多
The climatic variations since the Little Ice Age recorded in the Guliya Ice Core are discussed based on glacial δ18O and accumulation records in the Guliya Ice Core. Several obvious climate fluctuation events since 1...The climatic variations since the Little Ice Age recorded in the Guliya Ice Core are discussed based on glacial δ18O and accumulation records in the Guliya Ice Core. Several obvious climate fluctuation events since 1570 can be observed according to the records. In the past 400 years, the 17th and 19th centuries are relatively cool periods with less precipitation, and the 18th and 20th centuries are relatively warm periods with high precipitation. The study has also revealed the close relationship between temperature and precipitation on the plateau. Warming corresponds to high precipitation and cooling corresponds to less precipitation, which is related with the influence of monsoon on this region.展开更多
Whether the solar activity was very low, and especially whether the solar cycle existed, during the Maunder Minimum (1645-1715 AD), have been disputed for a long time. In this paper we use the Guliya NO3 data, which c...Whether the solar activity was very low, and especially whether the solar cycle existed, during the Maunder Minimum (1645-1715 AD), have been disputed for a long time. In this paper we use the Guliya NO3 data, which can reflect the solar activity, to analyze the characteristics of the solar activity during the Maunder Minimum. The results show that the solar activity was indeed low, and solar cycle displayed normal as present, i.e. about 11 a, in that period. Moreover, it was found that the solar activity contains a 36-year periodic component probably, which might be related to the variations in the length of the sunspot cycle. This finding is of importance for the study of the relationship between the sun variability and the Earth climate change.展开更多
The Guliya Ice Cap is the largest (with a total area of 376.1 m2 and an area cf 131 2 m2 at the flat top), highest (6 700 m a. s.l.) and coldest (with an ice temperature of -19℃ at 10 m depth) ice cap found in Centra...The Guliya Ice Cap is the largest (with a total area of 376.1 m2 and an area cf 131 2 m2 at the flat top), highest (6 700 m a. s.l.) and coldest (with an ice temperature of -19℃ at 10 m depth) ice cap found in Central Asia so far. From 1990 to 1992, the oxygen isotope ratios, microparticle concentrations, anions, cations of a large number of samples from snow pits and ice cores were analysed to study the climatic and environmental characteristics of the Guliya Ice Cap. Being frozen to bedrock and with extremely low ice temperature, the ideal climatic and environmental informarion was recorded in Guliya Ice Cap. The distinct annual and seasonal cycle characteristics of the oxygen isotope ratio, microparticle concentration, anion and cation provide bases to date precisely the high-resolution time series in the ice cap. Oxygen isotope ratios decreased, microparticle concentrations and various chemical elements increased in the colder periods, while oxygen isotope values increased, microparticle concentrations and various chemical elements decreased during warmer periods, and the interpretation of various abrupt events will be the key to restore systematically various kinds of climatic and environmental information recorded in this ice cap. The records in the Guliya ice cores indicate that climatic wanning which happened in the middle 1980s was one of the most impressive events during the past several decades.展开更多
Carrying dry and wet deposition records of aerosols in the mid-to upper-troposphereabove northwestern Qinghai-Xizang Plateau, the Guliya Ice Core extracted in 1992 at the el-evation of 6 400m on Guliya Ice Cap of west...Carrying dry and wet deposition records of aerosols in the mid-to upper-troposphereabove northwestern Qinghai-Xizang Plateau, the Guliya Ice Core extracted in 1992 at the el-evation of 6 400m on Guliya Ice Cap of western Kunlun Mt. has provided a uniqueopportunity to improve our understanding of atmospheric emvironment in this area. Onthe basis of studies on firn-ice transition of the ice cap, depositional processes展开更多
A 36CI peak was found in the predicted section of Guliya ice core, from the Qinghai-Tibetan Plateau, at about 37 kaBP. This cannot be interpreted by means of changes in the accumulation rate, but by the enhanced cosmo...A 36CI peak was found in the predicted section of Guliya ice core, from the Qinghai-Tibetan Plateau, at about 37 kaBP. This cannot be interpreted by means of changes in the accumulation rate, but by the enhanced cosmogenic isotope production rate in the atmosphere. Compared with the records of 10Be and 36CI in the other regions, the peaks of the cosmogenic isotopes are global and can be considered as time marks. An intriguing fact is that the peaks coincided with cold periods.展开更多
基金Under the auspices of the G1998040802 BX2001-03 and KXCX2-301 programs
文摘The correlations of the d18Omax in the shallow ice core from the Guliya ice cap on the Tibetan Plateau with the global sea surface temperatures (SST) and height at the 500 hPa over the Northern Hemisphere were analyzed. The correlated regions on oceans that have a significant influence on the d18Omax in the Guliya ice core are all located in ocean currents, or convergent regions of currents. They are the eastern Equatorial Pacific, the Northern Pacific Current, the Hot Pool in the eastern Indian Ocean, the Mozambique Current, the Northern Atlantic Current, the Canary Current and the Atlantic Equatorial Current. The d18Omax in the Guliya ice core has negative correlations with the SST located in the lower latitudes, and positive correlations with the SST in the middle latitudes. The correlated areas at the 500 hPa that have a great impact on the d18Omax are located in the subtropical highs over the mid-low-latitude oceans and the long-wave trough area over Balkhash Lake, where there are marked negative correlations between the heights in those areas and the d18Omax. The influencing mechanism is displayed by the diversity of the vapor origins transported to the Guliya region. The strengths of the European ridge and the ridge over Baikal Lake have notable positive correlations with the d18Omax. The two systems indirectly influence the vapor transportation towards the Guliya region by the adjustment of long-wave trough and ridge.
基金Project supported by the Climbing Program of the State Eighth Five-Year Plan and the National Natural Science Foundation of China
文摘The climatic and environmental variations since the Last Interglaciation are reconstructed based on the study of the upper 268 m of the 309-m-long Guliya ice core. Five stages can be distinguished since the Last Interglaciation from the δ18O record in the Guliya ice core: Stage 1 (Deglaciation), Stage 2 (the Last Glacial Maximum), Stage 3 (interstadial), Stage 4 (interstadial in the early glacial maximum) and Stage 5 (the Last Interglaciation). Stage 5 can be divided further into 5 substages; a, b, c, d, e. The δ18O record in the Guliya ice core indicates clearly the close correlation between the temperature variation on the Tibetan Plateau and the solar activities. The study indicates that the solar activity is a main forcing to the climatic variation on the Tibetan Plateau. Through a comparison of the ice core record in Guliya with that in the Greenland and the Antarctic, it can be found that the variation of large temperature variation events in different parts of the world is generally the same, but the variation amplitude of temperature is different.
基金Project supported by the CAS Key Projects National Climbing Program (Grant Nos. KZ951-A1-204-02-03, KZ951-A1-402-03, 95-Yu-24).
文摘Based on a comparative study of the Guliya ice core with the Greenland GRIP ice core, the abrupt climatic changes on the Tibetan Plateau during the Last Ice Age have been examined. The major stadial-interstadial events and 7 warm events (Brφrump, Odderade, Oerel, Glinde, Hengelo, Denekamp, BQlling) are consistent in the two ice cores. However, there are some unique features in the Guliya ice core records. The transition from warm to cold periods in the Guliya ice core is faster than that in the Greenland GRIP ice core. The magnitude of the climatic changes in the Guliya ice core is also larger than that in the Greenland GRIP ice core. Another significant feature of the Guliya ice core records is that there is a series of cycles of about 200 a from 18 to 35 kaBP. 22 warm events and 20 cold events with a fluctuation magnitude of 71 have been distinguished. The warm and cold events with a fluctuation magnitude within 3 ℃ are as high as 100. It is speculated that the abrupt climatic changes in different periods are caused by different driving forces. The abrupt climatic changes from stadial to interstadial are driven by insolation and are amplified by the snow cover on the Tibetan Plateau. The abrupt climatic changes on shorter time scales are the consequence of interaction between sun activity and the monsoon.
基金Project supported by the Ministry of Science and Technology of China and the KZ 951-A1-202-04 project of the Chinese Academy of Sciences.
文摘The high-resolution records of δ18O and snow accumulation variations from the Guliya ice core provide valuable data for research on climatic variations at a decadal resolution during the past 2000 years in China. Based on the ice core data, five spells have been divided: the warm and wet period before 270 AD, the cold and dry period between 280 and 970 AD, the moderate and dry period between 970 and 1510 AD, the well-defined' Little Ice Age 'with drastic cold-warm fluctuations between 1510 and 1930 AD and the warming period since 1930 AD. According to the combination of temperature and precipitation, cold events (55 times) surpass warm ones (26 times) , and dry events (55 times) surpass wet ones (45 times) . Cold-wet events (14 times) are less than cold-dry ones (16 times) , while warm-wet events (10 times) are more than warm-dry ones (4 times) . If the difference of 2‰ in δ18O (corresponding to 3K in temperature) between two or three adjacent decades is taken as the criterion of it, the abrupt change has taken place 33 times or so since the 3rd century. Among them are four large ones, occurring in 250-280, 550-580, 1220-1260, and 1520-1560 AD respectively. Comparison of the ice core data with the latest comprehensive research results on historical documents of East China shows that the great climatic events appeared simultaneously or at the same age in the ice core record and in the documentary data, suggesting that consistences and similarities in climatic variation among different areas are far away from each other in the lower to mid-latitudes. However, there is a great difference between them during the Medieval Warm Period, which is conspicuous in the historical documents but not in the ice core. In addition, the first cold event of the Little Ice Age on East China was 60 years earlier than that of the Guliya Ice Cap, when the degree of cooling in West China is more intensive than that of East China. But the third cold event in East China lagged behind that in West China during the late 19th century. The 1820s cold event in both West and East China may be caused by the magnificent Tambora volcanic eruption in 1815.
基金This work was supported by the Chinese National Committee of Science and Technology (Grant No. G1998040800)the Chinese Academy of Sciences (Grant No. KZCX1-10-02)+1 种基金 the National Natural Science Foundation of China (Grant No. 49801004) the US NSF-ESH
文摘Evidence for the '8.2 ka cold event' has been provided mostly from the circum-North Atlantic area. However, whether this cold event occurred in other places is a key to understanding its cause. Here, we provide the evidence for the '8.2 ka cold event' from the Guliya ice core in the northwest Tibetan Plateau, and it was found that the peak cooling (-8.3-8.2 ka) in this ice core was about 7.8-10°C, which was larger than the cooling in the North Atlantic region. The primary causes for this episode were diminished solar activity and weakened thermohaline circulation. Moreover, another weak cold event, centered about 9.4 ka, was also recorded in the Guliya ice core record. These two cold events were concurrent with the ice-rafting episodes in the North Atlantic during the early Holocene, which implies that the millennial-scale climatic cyclicity might exist in the Tibetan Plateau as well as in the North Atlantic.
基金Project supported by the Climbing Program and the National Natural Science Foundation of China.
文摘The past temperature and precipitation variations are recorded precisely and continuously in μ18O and glacial accumulation records in the Guliya ice core. Fight warm periods and seven cold periods can be distinguished in the past 2000 a. Of the four most intensive cold periods, three are in the Little Ice Age and one in the 11th - 12th century. The variation of precipitation is relatively small compared with that of temperature. Five humid periods and four dry periods occurred in the past 2 000 a. The long-term variation of temperature is positively correlated with that of precipitation according to the Guliya ice core record, but the variation of precipitation lags behind the variation of temperature.
文摘By the analyses of Guliya ice core on the Ti-betan Plateau, it was found that the calcium (Ca2+) origi-nated from the terrestrial source is the main cation of soluble aerosol and a good proxy of the atmospheric component and environment in the mountain ice core located in the mid-low latitude arid regions. Evident variation of Ca2+ concentration has been found in the Guliya ice core since the Last Intergla-ciation with two relatively strong increase periods and two weak increase periods. These variations are generally related to climatic changes: high Ca2+ concentration periods coincide with cold periods and low Ca2+ concentration periods coin-cide with warm periods. However, Ca2+ concentration does not always decrease (increase) with climate warming (cool-ing). The magnitude and phase of Ca2+ concentration does not always match temperature either. The changes of at-mospheric circulation, land surface condition and atmos-pheric humidity might be important factors which influence Ca2+ concentration besides temperature.
文摘Based on the study of oxygen isotope and mi-croparticle in the Guliya ice core, atmospheric dust and en-vironmental changes in the northwest Tibetan Plateau since the last interglacial were revealed. The microparticle record indicates that low dust load on the Plateau in the interglacial. Particle concentration increased rapidly when the climate turned into the last glacial and reached the maximum during the MIS 4. In the Last Glacial Maximum, however, the en-hancement of microparticle concentration was slight, differ-ing to those in the Antarctic and Greenland. On the orbital timescale, both the temperature on the Tibetan Plateau and summer solar insolation in the Northern Hemisphere had their impact on the microparticle record, but the difference in phase and amplitude also existed. Though having the same dust source, microparticle records in the ice cores on the Tibetan Plateau and the Greenland seem to have different significance.
文摘The variations of NO\+-\-3 concentration in the Guliya ice core are reconstructed for recent about 1 000 a. Spectrum analysis of NO\+-\-3 indicates significant periodicities in the variations of NO\+-\-3 concentration, which coincide with the periodicities of the solar activity. Therefore, a positive correlation between the variations of NO\+-\-3 concentration and the solar activity is found.
文摘The climatic variations since the Little Ice Age recorded in the Guliya Ice Core are discussed based on glacial δ18O and accumulation records in the Guliya Ice Core. Several obvious climate fluctuation events since 1570 can be observed according to the records. In the past 400 years, the 17th and 19th centuries are relatively cool periods with less precipitation, and the 18th and 20th centuries are relatively warm periods with high precipitation. The study has also revealed the close relationship between temperature and precipitation on the plateau. Warming corresponds to high precipitation and cooling corresponds to less precipitation, which is related with the influence of monsoon on this region.
文摘Whether the solar activity was very low, and especially whether the solar cycle existed, during the Maunder Minimum (1645-1715 AD), have been disputed for a long time. In this paper we use the Guliya NO3 data, which can reflect the solar activity, to analyze the characteristics of the solar activity during the Maunder Minimum. The results show that the solar activity was indeed low, and solar cycle displayed normal as present, i.e. about 11 a, in that period. Moreover, it was found that the solar activity contains a 36-year periodic component probably, which might be related to the variations in the length of the sunspot cycle. This finding is of importance for the study of the relationship between the sun variability and the Earth climate change.
文摘The Guliya Ice Cap is the largest (with a total area of 376.1 m2 and an area cf 131 2 m2 at the flat top), highest (6 700 m a. s.l.) and coldest (with an ice temperature of -19℃ at 10 m depth) ice cap found in Central Asia so far. From 1990 to 1992, the oxygen isotope ratios, microparticle concentrations, anions, cations of a large number of samples from snow pits and ice cores were analysed to study the climatic and environmental characteristics of the Guliya Ice Cap. Being frozen to bedrock and with extremely low ice temperature, the ideal climatic and environmental informarion was recorded in Guliya Ice Cap. The distinct annual and seasonal cycle characteristics of the oxygen isotope ratio, microparticle concentration, anion and cation provide bases to date precisely the high-resolution time series in the ice cap. Oxygen isotope ratios decreased, microparticle concentrations and various chemical elements increased in the colder periods, while oxygen isotope values increased, microparticle concentrations and various chemical elements decreased during warmer periods, and the interpretation of various abrupt events will be the key to restore systematically various kinds of climatic and environmental information recorded in this ice cap. The records in the Guliya ice cores indicate that climatic wanning which happened in the middle 1980s was one of the most impressive events during the past several decades.
文摘Carrying dry and wet deposition records of aerosols in the mid-to upper-troposphereabove northwestern Qinghai-Xizang Plateau, the Guliya Ice Core extracted in 1992 at the el-evation of 6 400m on Guliya Ice Cap of western Kunlun Mt. has provided a uniqueopportunity to improve our understanding of atmospheric emvironment in this area. Onthe basis of studies on firn-ice transition of the ice cap, depositional processes
文摘A 36CI peak was found in the predicted section of Guliya ice core, from the Qinghai-Tibetan Plateau, at about 37 kaBP. This cannot be interpreted by means of changes in the accumulation rate, but by the enhanced cosmogenic isotope production rate in the atmosphere. Compared with the records of 10Be and 36CI in the other regions, the peaks of the cosmogenic isotopes are global and can be considered as time marks. An intriguing fact is that the peaks coincided with cold periods.
