Climate records obtained by most instruments are relatively short in time, which limits the study of climate change, necessitating the use of proxy data to extend records to the past. It was not until the late 1940s that atmospheric data of sufficient quality and spatial resolution were available to determine the main patterns of climate change such as the North American Pacific model and the Pacific Decadal Oscillation. The global ice cores are from the north and south poles and the third pole, and there are also mountain glaciers in Alaska. The ice core data obtained in that area are of great significance for revealing the climate in North America and climate change in the Arctic regions at both low and high latitudes. The physical meaning of each variable: First column: time; second column: accumulation rate data; third column: oxygen isotope data value
This data set contains the oxygen isotope, dust, anion and accumulation data obtained from the deep ice core drilled in 1992 in the Guliya ice cap, which is located in the west Kunlun Mountains on the Tibetan Plateau. The length of the ice core was 308.6 m. The ice core was cut into samples, 12628 of which were used to measure the oxygen isotope values, 12480 of which were used to measure the dust concentrations, and 9681 of which were used to measure the anion concentrations. Data Resource: National Centers for Environmental Information（http://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/ice-core）. Processing Method: Average. The data set contains 4 tables, namely: oxygen isotope, dust and anion data from different depths in the Guliya ice core, 10-year mean data of oxygen isotopes, dust, anions and net accumulation in the Guliya ice core, 400-year mean data of oxygen isotopes, dust and anions in the Guliya ice core, and chlorine-36 data from different depths. Table 1: Data on oxygen isotopes, dust and anion concentrations at different depths in the Guliya ice core. a. Name explanation Field 1: Depth Field 2: Oxygen isotope value Field 3: Dust concentration (diameter 0.63 to 20 µm) Field 4: Cl- Field 5: SO42- Field 6: NO3- b. Dimensions (unit of measure) Field 1: m Field 2: ‰ Field 3: particles/mL Field 4: ppb Field 5: ppb Field 6: ppb Table 2: 10-year mean oxygen isotope, dust, anion and net accumulation data for the Guliya ice core (0-1989) a. Name explanation Field 1: Start time Field 2: End time Field 3: Oxygen isotope value Field 4: Dust concentration (diameter 0.63 -20 µm) Field 5: Cl- Field 6: SO42- Field 7: NO3- Field 8: Net accumulation b. Dimensions (unit of measure) Field 1: Dimensionless Field 2: Dimensionless Field 3: ‰ Field 4: particles/mL Field 5: ppb Field 6: ppb Field 7: ppb Field 8: cm/year Table 3: 400-year mean oxygen isotope, dust and anion data for the Guliya ice core. a. Name explanation Field 1: Time Field 2: Oxygen isotope Field 3: Dust concentration (diameter 0.63-20 µm) Field 4: Cl- Field 5: SO42- Field 6: NO3- b. Dimensions (unit of measure) Field 1: Millennium Field 2: ‰ Field 3: particles/mL Field 4: ppb Field 5: ppb Field 6: ppb Table 4: Chlorine-36 data at different depths a. Name explanation Field 1: Depth Field 2: 36Cl Field 3: 36Cl error Field 4: Year b. Dimensions (unit of measure) Field 1: m Field 2: 104 atoms g-1 Field 3: % Field 4: Millennium
The modern sporopollen identification results of five different geomorphic types in the middle reaches of Heihe River show that there are 39 sporopollen types, 22 main types, belonging to 6 different vegetation types in 45 topsoil samples distributed in the desert vegetation belt. The SPOROPOLLEN ASSEMBLAGES with high percentage of sporopollen in the sporopollen map were selected to represent different geomorphic types. It was found that five geomorphic types (dune, alluvial proluvial fan, flood plain, riverbed and wetland) could be expressed by different combinations of nine sporopollen.
This data set contains a deep drilling paleomagnetic age data near the open sea in the middle reaches of Heihe River. The borehole is located at 99.432 E and 39.463 n with a depth of 550m. The samples of paleomagnetic age were taken at the interval of 10-50 cm. The paleomagnetic test was carried out in the Key Laboratory of Western Ministry of environmental education of Lanzhou University. The primary remanence of the samples was obtained by alternating demagnetization and thermal demagnetization, and the whole formation magnetic formation was obtained by using the primary remanence direction of each sample, and then the sedimentary age of the strata was obtained by comparing with the standard polarity column. The results show that the bottom boundary of the borehole is about 7 Ma and the top boundary is 0 ma.
Since the formation of Heihe River, sporopollen data samples have been collected from the drilling strata of Da'ao well in the middle reaches of Heihe River. Drilling location: 39.491 n, 99.605 E. The drilling depth is 140 meters. 128 samples of sporopollen are collected from top to bottom. At present, there are 19 data of sporopollen results, which are distributed in each sedimentary facies from top to bottom. The sporopollen samples were removed from carbonate, organic matter, silicate and other impurities in the laboratory, and the species and data of sporopollen were identified under the microscope. Sporopollen results mainly include the percentage content and number of trees, shrubs, herbs, aquatic, ferns and other families and genera.
Based on the study of the terrace formation age in the upper reaches of heihe river, photoluminescence samples were collected from the sediments of grade 6 river terrace near the upper reaches of qilian river.The quartz particles (38-63 microns) in the sample were isolated in the laboratory, the equivalent dose and dose rate in the quartz particles were measured, and the photoluminescence age of the sample was finally obtained.The obtained ages range from 5ka to 82ka, corresponding to the years of cutting down the terraces of all levels.
Since the formation of heihe, palynology data samples were collected from the borehole formation of dasunken well in the middle reaches of heihe.Borehole location: 39.491 n, 99.605 e.The borehole has a depth of 140 meters and 18 palynological samples are collected from top to bottom. Currently, there are 3 palynological results, which are distributed in each sedimentary phase from top to bottom.Impurities such as carbonate, organic matter and silicate were removed from palynology samples in the laboratory, and the palynology types and data were identified under the microscope.Palynology results mainly included the percentage and number of trees, shrubs, herbs, aquatic and ferns.
This data set is the hydrogen isotope data of leaf wax from 10 m core of Qinghai Lake in Tengchong, Southeast of Qinghai Tibet Plateau. Tengchong Qinghai Lake is a small crater lake in Gaoligong Mountain, Southwest China. Core samples were collected at about 4m in the center of the lake in 2017. Ams-14c dating was used to establish the age series. The n-alkane leaf wax hydrogen isotope was determined and analyzed by Agilent 6890 GC gas chromatograph and Deltaplus XL type chromatography isotope mass spectrometry. The data reflect the information of atmospheric precipitation isotope in this area, and play an important role in the study of monsoon precipitation changes in southwest monsoon region in the past 40000 years. Data acquisition, pre-processing extraction and instrument testing were completed in strict accordance with the relevant operating procedures.
Lake sediment is important archive for reconstructing the past climate change, in which the chronological framework of sediments is the basis. Varve is a kind of sedimentary lamina formed in pairs in lake sediments, usually with one year as a cycle. Supported by the projects the Strategic Priority Research Program of Chinese Academy of Sciences “Pan-Third Pole Environment Study for a Green Silk Road (Pan-TPE)” and The Second Tibetan Plateau Scientific Expedition and Research, the authors obtained a 1-meter long sediment gravity core from Jiangco in the central Tibet Plateau, and found well preserved varves. Subsequently, core thin sections were made, and the varve and its thickness were counted and measured to obtain the chronological sequence from 81 A.D. to 2015. The precipitation in this area in the past 2000 years has been reconstructed by using the percentage of coarse-grained layer thickness in the total varve thickness, which represents the precipitation. High resolution and high-precision chronology and precipitation records can provide reliable background of climate and environmental change, and provide reference for paleoclimate simulation and the rise and fall of ancient civilization.
Pollen and spores extracted from sediment are considered as the important proxy in reconstructing past vegetation and climate, and which plays essential role in investigating environmental evolution during the Quaternary. Accurate identification of pollen and spore is the base for palynological research, which determines it is quite necessary to establish modern atlas for pollen and spore. Supported by the projects the Strategic Priority Research Program of Chinese Academy of Sciences “Pan-Third Pole Environment Study for a Green Silk Road (Pan-TPE)” and The Second Tibetan Plateau Scientific Expedition and Research, authors completed the vegetation and soil surveys in 2018 for the alpine meadow in the east Tibetan Plateau (including Yushu Prefecture, Changdu City, Ganzi prefecture, Naqu City) and alpine forest in the southeast Tibetan Plateau (Linzhi City) , and collected 401 specimens for anther of flowering plants and sporangium of ferns. Pollen and spores were extracted and from these specimens using the standard acid-alkali approach and acetolysis (9:1 mixture of acetic anhydride and sulphuric acid) treatment, and further were refrigerated in glycerin. More than two photographs were took for each pollen and spore type, using the LEICA-dm-2500 optical microscope and its imaging system with scale. The atlas of pollen and spore morphology will be a valuable reference for palynology research and teaching.