| According to the glacier inventory,the amount of China's glacier resources is the forth in the world.And China is the biggest country with mountain glaciers in the middle and low latitude.Especially the Qinghai-Tibetan plateau has the most considerable glacier resources in China.This makes the glaciers play a vital role in the changes of the western water resources.So the study on the glacier variation has important scientific and practical significance to the global change and the water resource change of west arid zone in China.Due to the special geographical position and formidable natural conditions of mountain glaciers,and the limitation of the early remote sensing satellite imaging technology,It is difficult to obtain high quality remote sensing images to monitor the change of glacier long time series.At present,Most of the studies on regional glacier changes have a time span of less than 10 years?mainly concentrated in the2000 years later?.Therefore,there is a lack of early long time series of regional glacier change observation data.Spy satellite KH-9 data has the advantages of high spatial resolution,wide ground coverage,high base ratio,and early imaging time etc.,which can provide a good basic data source for the study of long-term temporal mass balance of mountain glaciers.In this paper,it is taken as the main data source to extract the mass balance of mountain glaciers between 1974 and 2000.The elevation data obtained by ICEsat sensor has the advantages of high precision and small footprint,which can extend the time scale of the research on extraction of parameters of mountain glacier change in this paper,and is used to extract the thickness change information of glacier after 2000?2003-2009?.In addition,in view of the increasing number of domestic high-resolution optical remote sensing satellite data,but in the mountain glacier velocity monitoring of Chinese satellite remote sensing data is not used much,In this paper,the GF-1 satellite image data made in China was used to extract the glacier's velocity between 2013 and 2017,so as to verify the feasibility of GF-1 data in mountain glacier velocity monitoring application.The main contents and results of this paper are as follows:?1?A new automatic identification method of KH-9 image distortion cross symbol is proposed,which makes the correction error of KH-9 image distortion less than one pixel.On this basis,a detailed and complete technical process of KH-9image preprocessing and KH-9 DEM extraction is established.Combined with extracted KH-9 DEM and SRTM data,the characteristics of mass balance changes in early and long time series?1974-2000?of glaciers in the study area was obtained by geodetic measurement method.The results show that yalong glacier has been melting in the past 30 years,and the average mass balance is-0.30±0.04m w.e.×a-1;The average material balance of west kunlun glacier in the past 30 years is approximately or slightly positive.?2?This thesis introduced the ICEsat GLA14 altimetry data processing method in detail,and established the technical process of extracting the thickness change of mountain glaciers based on ICEsat data and SRTM data.The elevation changes from 2003 to 2009 of the glacier were extracted by the annual change trend robust regression method under the condition of 90%confidence.Results show that Yalong glacier in 2003-2009 has been in a state of apparent thickness thinning,the thinning amount up to 0.58 m?(6-1;The west kunlun glacier is thickening on the whole with an annual thickening of 0.20 m?(6-1.?3?This thesis analyzed spatiotemporal variation differences of mass balance and thickness change parameters between west kunlun glacier and yalong glacier,and studied the response characteristics of change parameters to climate change.It is found that yalong glacier,is very sensitive to temperature changes.Influenced by the continuous and significant increase of summer temperature,the surface of the glacier has a strong ablation.on the contrary,west kunlun glaciers slower response to climate change,is not sensitive to temperature changes,the rain became the dominant factor of climate change,increased rainfall inhibits glaciers melt,promote the accumulation of the glacier.so,the west kunlun glaciers were in a state of matter accumulation in 1974-2000 and 2003-200,and more rain makes matter accumulation after 2000 is also more obvious.?4?The extraction method of glacier velocity in frequency domain and phase correlation based on optical image is introduced in detail,and a complete extraction process of glacier velocity that can be used for gf-1 data is established.Using the domestic GF-1 data,yalong glacier velocity distribution characteristics of different period in 2013-2017 were extracted.Compared with landsat-8 data,the feasibility of gf-1 data in mountain glacier velocity extraction research was evaluated from the aspects of residual displacement in non-glacial stable region and the velocity of glacier main ice streamline profile.The results showed that GF-1 data was completely applicable to the extraction of mountain glacier velocity. |
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