I'm Leif Olmanson, I'm a researcher at the
University of Minnesota.
Minnesota is kind of a natural fit for using
Landsat for water quality assessments. It's a very
diverse state with over 10,000 lakes. Probably
like 20 years ago we started using Landsat for
water clarity assessments. And that led to a thing we
did about 15 years ago, was actually make our
data available in a google earth format on Lake Browser.
And having that data available has proven to be very popular.
Over the years we've seen the data with Landsat 8 now
much less noisy data then we've had in the past.
Also the processing of the data has improved a lot.
When we first started this, you had a lot of work to do
to get an image where you could actually use it. you
had to geometrically correct it, you had to do all kinds
of crazy stuff to actually start using it. Now we have
a lot of products like the surface reflectance product
And now just recently with the analysis ready data
basically you can start using it right away, which is
a big improvement.
Having this always changing land cover map will be a very
useful product for some of these projects that we have.
And also the methodology will be consistent over
time where what we've found is some of the older land
cover classifications, there's a different method used
every time it's done, so it's not conducive to
determining what's changing on the landscape so
having this continuous one method will be very
useful for lots of studies including lakes.
The largest thing that Landsat has is the archive.
I mean that's the most important thing. There's
no other sensor we can go back at look at in the
lakes. Some of the new ones might have some
better spectral bands or something that might
be able to identify chlorophyll better but
nobody has that that archive.
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