surface_temperature_tm for Landsat 7

[vjjan91]

Looks like your function works for LST for Landsat 5, but is there a function to calculate LST for Landsat 7?

Please help.

[sacridini]

Hi! Actually you can use the L5 function to get the same data from the L7 sensor too. :)

[eringregoire]

I'm still having an issue with L7 and calculating LST. Here is the code I'm using. I changed the one function to surface_temperature_tm but for whatever reason I still cannot get an accurate measure of the land surface temperature using this code and Landsat 7. Do you know if there is anything else I need to change in my code?

// LST 2002

var LST02 = ee.Image(
clippedCollection7.filterBounds(point)
.filterDate('2002-07-01', '2002-11-30')
.sort('CLOUD_COVER')
.first()
);
var new_toa_radiance = geet.toa_radiance(LST02, 8);
var brightness_temp_img = geet.brightness_temp_l7c(new_toa_radiance, true);
var l7_ndvi = geet.ndvi_l7(brightness_temp_img);
var img_pv = geet.prop_veg(l7_ndvi);
var lse = geet.surface_emissivity(img_pv);
var surfTemp_lse = geet.surface_temperature_tm(lse);
var im = surfTemp_lse.select("LST");
print(im);

[vjjan91]

@erin - Could you also provide a screenshot of the output ?

[eringregoire]

[eringregoire]

And the temperature range is 23 to 221 degrees.

[vjjan91]

Maybe a link to your code? (if possible) Thanks! Hopefully, @sacridini can figure it out.

[eringregoire]

https://code.earthengine.google.com/2b3e9f1eb3ce5a3d38882c48a7abfc52
Here is the link to my code. Thank you!!

[sacridini]

Hi guys, i'm working a lot in another project, so sorry for the delay.
eringregoire, i think this code could help you... that's the way i generate the LST layer:

    var geet = require('users/elacerda/geet:geet');
    var image_col = ee.ImageCollection(l5)
                      .filterBounds(roi)
                      .filterDate('2010-01-01', '2010-12-31')
                      .sort('CLOUD_COVER');
    var image = image_col.first();
    var toa = geet.toa_radiance(image, 6);
    var ndvi = geet.ndvi_l5(toa);
    var bt = geet.brightness_temp_l5c(ndvi, true);
    var propVeg = geet.prop_veg(bt);
    var lse = geet.surface_emissivity(propVeg);
    var lst = geet.surface_temperature_tm(lse);
    var lst_only = lst.select('LST');

The number of the band that you are using to call the toa_radiance function its really 8? As far as i know, the Landsat 7 have the same band numbers as Landsat 5, right? Another point is the order of the things and the variables that you area passing. I think it can be that...

I hope i was helpfull. Try this code that I gave you and then tell me if it worked. :)

Best,
Edu