Evergreen vs deciduous

[hamidrezaomidvar]

Do we have any land cover data set that distinguish between evergreen and deciduous vegetation? I found a potential method that we might be able to predict these two classes using two images. It is based on combination of NDVI and NDWI

[hamidrezaomidvar]

Some background:
There are two separate metrics that can separate vegetation and water.
The first one is NDVI as follows:

NIR and RED are near infrared and Red bands. This is a very good indicator of vegetations in the satellite images.
Another indicator is NDWI, which is a good indicator of water bodies:

where GREEN is the green band in the satellite data.
So far I have been using these two metric to predict water, vegetation, and others. However, there is another version of NDWI which is a good indicator of the amount of water (either in vegetation or water):

where SWIR is the shortwave infrared band. Let's take a look at these three features for Colombo:

You can see that NDVI and NDWI_1 can separate vegetation and water very good. NDWI_2 is a combination of water and vegetation.

So now I am thinking if we look at NDVI-NDWI_2, where NDVI values are from an image during the growing season, and NDWI_2 is from an image during non-growing season, then the value of NDVI-NDWI_2 should be high for deciduous vegetation, while it is small for other. This is what we see here for a forrest I plotted for north America:

So we can give this additional metric to our model to predict these kinds of vegetations. To do so, we need data sets containing these two different vegetations

[sunt05]

Have a look at this site:
http://data.ess.tsinghua.edu.cn

I'm not quite sure if it would be useful.

[hamidrezaomidvar]

Thanks, I will take a look.