= where X was VPD (hPa), f (X) was the flammability index, and a and b were fitting coefficients (wSeheeSreup plwemasenVtaPrDy S(ℎ2, F i)g,u r e S 2.2w) athsatthceapfltaumremdabbeihliatvyioinrdsiemx,ilaanrdto p aasnt dlite rawtuerree(efi.tgt.i,n[g36c–o3e8f]f)i...