John Christensen, It seems rather clear for me, that you do not really know, what homogenization, raw data, or measurement means. Please take it not personally, most people do not know the details. We have certainly not to live with the biases, homogenizations are made, to REMOVE THE BIASES. Everytime you make measurements these are full of biases. There are methodological biases, instrumental biases, personal biases etc. Everytime you make a measurement, you have to verify it. IN geochemistry we use standarts to do this sort of homogenisation. Every 10th measurement we do with any instrument is done for calibrating this instrument. If you ever have made measurements in chemistry or physics, you should know, that there are plenty of mistakes to do. It is not only to read a thermometer and write the measurement down. When later your standart appears not to be calibrated right, you have to rehomogenize all of your raw data again, the same, when you find earlier unknown biases. Imagine several 1000 stations, all with their own biases, changing over time, with instrument changes, operator changes etc, then you understand the importance of homogenisation, or in other words, veification of the raw data and correction of the raw data. Then you know, why raw data is not reported, because the raw data is utterly useless without homogenisation, for every measurement done. If you do not have the possibility to verify the raw date and correct it, then you have to remove the data, you can not use it. NASA and the other organisations are completely open with their way of homogenization, why it is done and how it is done. You find it when you dig in their homepage, and you find it, when you simply ask. If you really think, that we probably have to live with biases, then you must distinguish between your own perceptual biases, and instrumental etc. in the data. With the first you may live, with the later you are able to remove them through homogenization. regards Folke Kelm