In this paper

a new hyperspectral data model that estimates chlorophyll-a concentration（Chla） in Taihu Lake of summer is proposed.The model was developed based on measurement in situ in July 2004

and was validated by hyperspectral data in August 2004.Water samples were collected by Wuxi Taihu Lake Environment Monitoring Station and covered the typical water areas.At each site

hyperspectral data were measured ten times by field spectroradiometer ASD FieldSpec

and were converted into remote sensing reflectance.Different band combinations were calculated and compared

and the normalized band index was selected because it is more explicable.The model built by data in July 2004 is Chla（μg/L）=EXP（2.478+16.378N66）

where N66 is（R696-R661）/（R696+R661）.Goodness-of-fit statistics of the model R2 is 0.9051

and p<0.0001.Compared with other models

this one is more stable

and is of less absolute error when used to estimate Chla in August 2004.The works in the paper also showed that hyperspectral data model can be used to estimate Chla by month in the summer of Taihu Lake.