海冰密集度对全球气候变化研究有重要的意义,其反演结果的验证工作也被广泛关注,但结合多源数据反演,同时对两种算法验证的研究较少的现状,该文利用ASPeCt船测海冰密集度数据对Bootstrap算法和NASA Team (NT)算法基于SSM/I数据估算的海冰密集度精度进行验证,并与MODIS影像反演获得的海冰密集度进行对比。研究结果显示两种海冰密集度算法获得的反演结果与ASPeCt船测值偏差分别为2.26%和7.27%,均方根误差分别为11.39%和12.32%。相比之下,MODIS结果与ASPeCt船测海冰密集度比较得到偏差为3%,均方根误差为5.21%。Bootstrap算法、 NT算法与ASPeCt船测值比较的偏差和均方根误差显示两种算法精度相近;由于MODIS数据分辨率与ASPeCt船测数据相近,所以其反演精度较优;但因时空分辨率的限制,各种结果都具有一定的不确定性。
英文摘要:
Sea ice concentration has significant implications for climate change;therefore effective validation for its accuracy has been widely concerned.In this paper,the sea ice concentration which obtained by using Bootstrap algorithm and NASA Team(NT)algorithm based on the passive microwave radiometer special sensor microwave/imager(SSM/I)data was validated using the Antarctic sea ice processes and climate(ASPeCt)data,and its result was compared with the sea ice concentration data obtained from MODIS. Experimental results showed that the biases of Bootstrap and NT sea ice concentration compared with ASPeCt were 2.26%and 7.27%respectively,and the RMSE were 11.39%and 12.33%respectively;the bias for retrieval result from MODIS data was 3%,and RMSE was 5.21%;the accuracy of Bootstrap and NT algorithm were both great,while MODIS showed better accuracy benefiting from its higher spatial resolution which is closed to ASPeCt;meanwhile,all the results had uncertainties on account of spatial and temporal resolution.