Date: Wed, 8 Sep 1999 11:25:54 -0400 From: Changsheng Chen To: eegle-all@wings.glerl.noaa.gov Subject: Data needed to verify the model results Cc: ji@shark4.marsci.uga.edu Mime-Version: 1.0 Hi, Everyone, We are working on the 3-D modeling experiments for a case study over a period of March 1 to 31, 1998. We are trying to examine how the suspended sediment affect the lower trophic level food web over that period. To verify the model results, we need some water sample data of chla. We have looked at PSS survey data posted at the EEGLE web site and found that chla at three PSS sections, especially at Gary section, show a significant vertical gradient. But all other variables, such as suspended sediment, light attenuation, temperature, fluorence, etc all were vertically well mixed. Before using the PPS data to compare with our model, we really need to have some water sample data to see what difference it would be between PPS and water sample measurement. This would be critical for our modeling effort. I wish anybody, who has these data, could kindly provide us these data. Second questions here is that we need the information of the SRP released rate from suspended sediments. This information is also critical for us to test our hypothesis on the effects of suspended sediments on the food web. We think that suspended sediments affect the ecosystem by two ways: one is through modifying the light attenuation and the other is by releasing nutrients. If one knows about this information, please let us know it. If we don't have any data for Lake Michigan, would you suggest some literatures or references related to this topic? Third equestion is about PAR data. We need the PAR at the surface to estimate the light extinction coefficient. Do you know who has these data? Thanks in advances, Chen at UGA