You want to lower saturation. Load up the sandbox2 editor. Open a level.cry (ex. island.cry) from inside the levels>"level_name" folders. Then click the "terrain" drop down dialogue at the top of the editor and select "time of day." This opens the TOD editor. Then scroll down through the TOD scrub bars until you find the saturation variable. Don't bother with the numerical settings on the very right. Then double click on each yellow dot inbetween the first and last. You'll end up with only two yellow dots (the first and the last) and those will both be set to 1.0. Grab the first yellow dot and drag it down till you're at a saturation level of .43 (what I'm using for those shots).
To get the exact same look you'll also want to remove all the dots except for the first and last for the grain filter in TOD. You can then increase the grain to .24 (what I'm using for those shots). I then turn the sharpen filter down to zero but I only do this for gameplay because it can help smooth out the edges in combination with r_useedgeAA 2. I leave everything else at default.
The screenshots are taken at 4224x2376 and then down scaled to 1920x1080.