(MERCED, CALIF.) When heat waves hit the Western United States, the risk of wildfires quickly rises. The prolonged heat dries out vegetation, but that’s only part of the cause – heat waves also play other roles in spreading wildfires.
In a new study, our team of fire and climate scientists looked at two decades of wildfire activity in the West, from 2001 to 2024, and for the first time quantified the effect of heat waves on those fires.
kAm(6 6IA64E65 2 3:8 :>A24E[ 3FE E96 ?F>36CD DE:== DFCAC:D65 FDi (9:=6 962E H2G6D[ H9:49 H6 567:?65 2D E9C66 @C >@C6 4@?D64FE:G6 52JD H:E9 E6>A6C2EFC6D :? E96 E@A E6?E9 @7 9@EE6DE 52JD[ 244@F?E65 7@C @?=J `aT E@ `dT @7 H2C>\D62D@? 52JD[ H6 7@F?5 E92E caT @7 2== E96 2C62 3FC?65 3J 7:C6D 925 @44FCC65 5FC:?8 @C C:89E 27E6C 2 962E H2G6]k^Am
kAmk:>8 DC4lQ9EEADi^^52E2HC2AA6C]5H45?]?6E^'FKGd^7F==]A?8Q ^mk^Am
kAm|@C6@G6C[ E96 2>@F?E @7 E96 2C62 E92E 3FC?65 6249 52J H2D >@C6 E92? d_T =2C86C 5FC:?8 962E H2G6D E92? 5FC:?8 E96 4@@=6C 52JD C:89E 367@C6 E96 962E H2G6 3682? :? >2?J A2CED @7 E96 (6DE] x? D@>6 C68:@?D[ E96 5:776C6?46 H2D >F49 =2C86C – FA E@ b__T]k^Am
k9amw@H 962E H2G6D H@CD6? 7:C6 C:D<k^9am
kAmw62E H2G6D 4C62E6 4@?5:E:@?D E92E 72G@C H:=57:C6 :8?:E:@? 2?5 DAC625 :? 2 76H H2JD]k^Am
kAmu:CDE[ 9@E E6>A6C2EFC6D k2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^E96\FD\:D\D66:?8\DEC@?86C\DE@C>D\D@\H9J\2C6\5C@F89ED\86EE:?8\H@CD6\agadf`Qm:?4C62D6 E96 2E>@DA96C6’D 56>2?5 7@C >@:DEFC6k^2m[ >62?:?8 E96 C2E6 2E H9:49 E96 2:C 42? 6G2A@C2E6 >@:DEFC6 7C@> E96 =2?5 2?5 G686E2E:@?] pD 2 C6DF=E[ E96D6 7F6=D C2A:5=J 5CJ @FE[ >2<:?8 E96> 62D:6C E@ :8?:E6]k^Am
kAmw62E H2G6D 2=D@ =:>:E ?:89EE:>6 9F>:5:EJ] %96 5C:6C 2:C 2==@HD 7:C6D E@ C6>2:? 24E:G6 7@C =@?86C A6C:@5D 2?5 k2 9C67lQ9EEADi^^5@:]@C8^`_]`_bg^Dc`dge\_a`\_cbad\`Qm3FC? E9C@F89 >@C6 9@FCD @7 E96 ?:89Ek^2m]k^Am
kAm|2<:?8 >2EE6CD H@CD6[ 962E H2G6D 42? 4C62E6 4@?5:E:@?D 72G@C23=6 7@C =:89E?:?8 3642FD6 @7 E96 9@E[ F?DE23=6 2E>@DA96C6] (6 7@F?5 :?4C62D6D :? 4=@F5\E@\8C@F?5 =:89E?:?8[ :?4=F5:?8 “k2 9C67lQ9EEADi^^HHH]?D7]8@G^?6HD^5CJ\=:89E?:?8\42?\DA2C<\H:=57:C6D\6G6?\F?56C\H6EE6CQm5CJ” =:89E?:?8k^2m[ 5FC:?8 2?5 27E6C 962E H2G6D 24C@DD >2?J A2CED @7 E96 (6DE]k^Am
k7:8FC6mk:>8 2=ElQw@H 962E H2G6D 6I246C32E6 H:=57:C6 C:D<]Q DC4lQ9EEADi^^:>286D]E964@?G6CD2E:@?]4@>^7:=6D^fc`ehe^@C:8:?2=^7:=6\a_ae_e`b\df\63DH>I]A?8n:I=:3lC3\c]`]_U2>AjBlcdU2>Aj2FE@l7@C>2EU2>AjHlfc_U2>Aj7:El4=:AQ ^mk7:842AE:@?mp? :==FDEC2E:@? D9@HD 9@H 962E 6I246C32E6D H:=57:C6 C:D<] |F<6D9 zF>2Ck^7:842AE:@?mk^7:8FC6m
kAmsCJ =:89E?:?8 42? @44FC H96? E96 AC64:A:E2E:@? :? 2 DE@C> DJDE6> 6G2A@C2E6D 367@C6 :E C62496D E96 8C@F?5] %9:D EJA6 @7 =:89E?:?8 :D A2CE:4F=2C=J 52?86C@FD 3642FD6 :E 42? :8?:E6 G686E2E:@? H:E9@FE AC@5F4:?8 6?@F89 C2:?72== E@ 5@FD6 E96 7=2>6D]k^Am
kAm%96D6 724E@CD 4@>3:?6 E@ 96:89E6? E96 C:D< @7 H:=57:C6D] %92E C:D< @7E6? k2 9C67lQ9EEADi^^5@:]@C8^`_]``ae^D4:25G]262`affQmA6CD:DED 6G6? 27E6C E96 962E H2G6 6?5Dk^2m[ 2D 5CJ G686E2E:@? 2?5 5625 >2E6C:2= @? E96 8C@F?5 E6?5 E@ C6>2:? F?FDF2==J 5CJ 7@C 52JD 27E6C E6>A6C2EFC6D C6EFC? 4=@D6C E@ ?@C>2= – 2==@H:?8 7:C6D E@ 4@?E:?F6 8C@H:?8]k^Am
k9am%C6?5D :? 962E 2?5 7:C6Dk^9am
kAm%96 4@??64E:@? 36EH66? 962E H2G6D 2?5 H:=57:C6 24E:G:EJ :D 364@>:?8 :?4C62D:?8=J :>A@CE2?E 3642FD6 k2 9C67lQ9EEADi^^5@:]@C8^`_]`_ah^a_a_v{_gf_hfQm962E H2G6D 2C6 364@>:?8 >@C6 4@>>@?k^2m 2D 8=@32= E6>A6C2EFC6D C:D6[ k2 9C67lQ9EEADi^^HHH]>@?E6C6J32J2BF2C:F>]@C8^2?:>2=D\E96\@462?^D@=FE:@?D\E@\4=:>2E6\492?86^H92E\42FD6D\4=:>2E6\492?86Qm7F6=65 3J 8C66?9@FD6 82D 6>:DD:@?Dk^2m]k^Am
kAm$:?46 a__`[ E96 ?F>36C @7 962E H2G6 52JD 24C@DD (6DE6C? &]$] 7@C6DED 92D ?62C=J 5@F3=65] sFC:?8 E96 D2>6 A6C:@5[ E96 2>@F?E @7 7@C6DE 2C62 3FC?65 k2 9C67lQ9EEADi^^5@:]@C8^`_]``ae^D4:25G]262`affQm:?4C62D65 3J a]d E:>6Dk^2m] $EC:<:?8=J[ H:E9@FE E96 :?4C62D6 :? 962E H2G6 52JD D:?46 a__`[ H6 7@F?5 E92E E96 4F>F=2E:G6 2C6 @7 3FC?65 7@C6DE H@F=5 92G6 366? bfT D>2==6C]k^Am
k7:8FC6mk:>8 2=ElQp >2A @7 E96 H6DE6C? &]$] D9@HD E96 8C62E6DE :?7=F6?46 @7 962E H2G6D @? A2CED @7 r2=:7@C?:2[ ~C68@?[ }6G252[ x529@ 2?5 &E29[ 3FE 2== 2C62D H:E9 9:89 A6C46?E286D]Q DC4lQ9EEADi^^:>286D]E964@?G6CD2E:@?]4@>^7:=6D^fc`ehf^@C:8:?2=^7:=6\a_ae_e`b\df\2bgGf5]A?8n:I=:3lC3\c]`]_U2>AjBlcdU2>Aj2FE@l7@C>2EU2>AjHlfc_U2>Aj7:El4=:AQ ^mk7:842AE:@?mw62E H2G6D 92G6 2 3:886C :?7=F6?46 :? D@>6 C68:@?D E92? @E96CD] %96 >2A D9@HD E96 A6C46?E286 @7 E96 E@E2= 2C62 3FC?65 5FC:?8 2?5 :>>65:2E6=J 7@==@H:?8 962E H2G6D 7C@> |2J E@ ~4E@36C[ a__`\a_ac] k2 9C67lQ9EEADi^^5@:]@C8^`_]``ae^D4:25G]262`affQms>:EC: p] z2=2D9?:<@G[ 6E 2=][ a_aek^2mk^7:842AE:@?mk^7:8FC6m
kAmw@H6G6C[ ?@E 2== 64@DJDE6>D C6DA@?5 E96 D2>6 H2J]k^Am
kAm(9:=6 H6 7@F?5 2 DEC@?8 =@?8\E6C> C6=2E:@?D9:A 36EH66? :?4C62D:?8 962E H2G6D 2?5 :?4C62D:?8 3FC?65 2C62 :? 7@C6DED[ E9:D H2D ?@E E96 42D6 :? 8C2DD=2?5D 2?5 D9CF3=2?5D[ H96C6 E96 E@E2= 3FC?65 2C62 92D ?@E :?4C62D65] x? 8C2DD=2?5D 2?5 D9CF3=2?5D[ E96 2>@F?E @7 =2?5 E92E 3FC?D :? 2 8:G6? J62C :D :?7=F6?465 >@C6 DEC@?8=J 3J E96 2>@F?E @7 2G2:=23=6 G686E2E:@? E92? 3J 962E 2=@?6]k^Am
k7:8FC6mk:>8 2=ElQQ DC4lQ9EEADi^^:>286D]E964@?G6CD2E:@?]4@>^7:=6D^fc`ehg^@C:8:?2=^7:=6\a_ae_e`b\df\37;3=5]A?8n:I=:3lC3\c]`]_U2>AjBlcdU2>Aj2FE@l7@C>2EU2>AjHlfc_U2>Aj7:El4=:AQ ^mk7:842AE:@?mw@H 3FC?65 2C62 2?5 =:89E?:?8\42FD65 H:=57:C6 :8?:E:@?D :?4C62D6 5FC:?8 2?5 27E6C 962E H2G6D[ 7C@> 2 C6G:6H @7 H:=57:C6D :? E96 (6DE6C? &]$] 7C@> a__` E@ a_ac] %96 492CE D9@HD E96 A6C46?E286 :?4C62D6 6249 52J 4@>A2C65 E@ =6G6=D 367@C6 2 962E H2G6] u@C 6I2>A=6[ @? 2G6C286[ E96 D6G6?E9 52J 27E6C E96 962E H2G6 DE2CED AC@5F46D 2? 2=>@DE a__T :?4C62D6 :? 7@C6DE 3FC?65 2C62 4@>A2C65 E@ E96 4@?5:E:@?D E92E 6I:DE65 367@C6 E96 962E H2G6] y@9? p32EK@8=@Fk^7:842AE:@?mk^7:8FC6m
k9amp 7FEFC6 H:E9 6G6? 5C:6C 962E H2G6Dk^9am
kAmr=:>2E6 492?86 :D 42FD:?8 (6DE6C? &]$] DF>>6CD E@ k2 9C67lQ9EEADi^^HHH]4=:>2E646?EC2=]@C8^4=:>2E6\>2EE6CD^DF>>6C\A24<286QmEC6?5 9@EE6C 2?5 5C:6Ck^2m] r@?D6BF6?E=J[ C6=2E:G6 9F>:5:EJ 5FC:?8 962E H2G6D 92D 2=D@ 564=:?65 :? C646?E 564256D[ 6DA64:2==J :? 7@C6DE65 C68:@?D @7 r2=:7@C?:2[ ~C68@? 2?5 (2D9:?8E@?]k^Am
kAm%96D6 5C:6C 962E H2G6D 2AA62C A2CE:4F=2C=J 67764E:G6 2E :?4C62D:?8 H:=57:C6 24E:G:EJ] p=@?8D:56 k2 9C67lQ9EEADi^^5@:]@C8^`_]`_bg^Dc`cef\_ad\debbb\gQm=@?8\DE2?5:?8 7:C6 567:4:EDk^2m[ H9:49 C6DF=E65 7C@> E96 AC24E:46 @7 BF:4<=J 6IE:?8F:D9:?8 7:C6D C2E96C E92? 2==@H:?8 =@H\=6G6= 7:C6D E@ 3FC? 2H2J 7@C6DE 563C:D[ E96D6 724E@CD 92G6 6D42=2E65 E96 A@E6?E:2= 7@C =2C86 7:C6D :? E96 (6DE]k^Am
kAm(:=57:C6 7@C642DED 2=C625J 244@F?E 7@C 724E@CD DF49 2D H:?5[ 9F>:5:EJ 2?5 7F6= 5CJ?6DD[ 3FE E96J EJA:42==J 92G6 ?@E :?4=F565 962E H2G6D] ~FC C6D62C49 DF886DED E92E 962E H2G6D 56D6CG6 8C62E6C 2EE6?E:@?[ 2D E96J 2C6 ?@E ;FDE A6C:@5D @7 F?4@>7@CE23=6 k2 9C67lQ9EEADi^^HHH]2A92]@C8^AF3=:42E:@?D^AF3=:4\962=E9\?6HDH:C6^AF3=:4\962=E9\?6HDH:C6^2CE:4=6D^6IEC6>6\962E\<:==D\>@C6\A6@A=6\E92?\2?J\@E96C\6IEC6>6\H62E96C\6G6?EQm2?5 D@>6E:>6D 5625=Jk^2m H62E96C[ 3FE 2C6 2=D@ :?4C62D:?8=J :>A@CE2?E 5C:G6CD @7 H:=57:C6 C:D<]k^Am
kAmk6>m%9:D 2CE:4=6 :D C6AF3=:D965 7C@> k2 9C67lQ9EEAi^^E964@?G6CD2E:@?]4@>^FDnFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?lC6=2E65\=:?<\_U2>AjFE>04@?E6?El2CE:4=6\agd`agQm%96 r@?G6CD2E:@?k^2m[ 2 ?@?AC@7:E[ :?56A6?56?E ?6HD @C82?:K2E:@? 3C:?8:?8 J@F 724ED 2?5 ECFDEH@CE9J 2?2=JD:D E@ 96=A J@F >2<6 D6?D6 @7 @FC 4@>A=6I H@C=5] xE H2D HC:EE6? 3Ji k2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^AC@7:=6D^5>:EC:\<2=2D9?:<@G\af_egbbnFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQms>:EC: z2=2D9?:<@Gk^2m[ k6>mk2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^:?DE:EFE:@?D^F?:G6CD:EJ\@7\42=:7@C?:2\>6C465\a_denFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQm&?:G6CD:EJ @7 r2=:7@C?:2[ |6C465k^2mk^6>mj k2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^AC@7:=6D^4@?8\J:?\af_haa_nFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQmr@?8 *:?k^2m[ k6>mk2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^:?DE:EFE:@?D^F?:G6CD:EJ\@7\42=:7@C?:2\>6C465\a_denFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQm&?:G6CD:EJ @7 r2=:7@C?:2[ |6C465k^2mk^6>mj k2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^AC@7:=6D^>259F=:<2\8FC2K252\af_haaanFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQm|259F=:<2 vFC2K252k^2m[ k6>mk2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^:?DE:EFE:@?D^F?:G6CD:EJ\@7\42=:7@C?:2\>6C465\a_denFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQm&?:G6CD:EJ @7 r2=:7@C?:2[ |6C465k^2mk^6>m[ 2?5 k2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^AC@7:=6D^>F<6D9\<F>2C\af_haabnFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?l3J=:?6\=:?<U2>AjFE>04@?E6?El2CE:4=6\agd`agQm|F<6D9 zF>2Ck^2m[ k6>mk2 9C67lQ9EEADi^^E964@?G6CD2E:@?]4@>^:?DE:EFE:@Tbr^6>TbtTbr^ATbtTbrATbtTbrDEC@?8Tbt#625Ta_>@C6iTbr^DEC@?8TbtTbr3CTa_^TbtTbrF=TbtTbr=:TbtTbr2Ta_9C67lQm(:=57:C6D 2C6 C6G6CD:?8 p>6C:42’D AC@8C6DD @? @K@?6 A@==FE:@?[ E96 >2:? :?8C65:6?E :? D>@8k^2mk^6>mk^6>mk^Am
k=:mk6>mk2 9C67lQ9EEAi^^E964@?G6CD2E:@?]4@>^9@H\2>6C:42\4@FCE65\:?4C62D:?8=J\56DECF4E:G6\H:=57:C6D\2?5\H92E\E92E\>62?D\7@C\AC@E64E:?8\9@>6D\E@52J\acfc`bnFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?lC6=2E65\=:?<`U2>AjFE>04@?E6?El2CE:4=6\agd`agQmw@H p>6C:42 4@FCE65 :?4C62D:?8=J 56DECF4E:G6 H:=57:C6D − 2?5 H92E E92E >62?D 7@C AC@E64E:?8 9@>6D E@52Jk^2mk^6>mk^=:m
k=:mk6>mk2 9C67lQ9EEAi^^E964@?G6CD2E:@?]4@>^E96\H6DED\:4@?:4\7@C6DED\2C6\:?4C62D:?8=J\DECF88=:?8\E@\C64@G6C\7C@>\H:=57:C6D\2=E6C:?8\9@H\7:C6D\3FC?\4@F=5\3@@DE\E96:C\492?46D\a__eegnFE>0D@FC46l{66U2>AjFE>0>65:F>lC6=2E65\=:?<U2>AjFE>042>A2:8?lC6=2E65\=:?<aU2>AjFE>04@?E6?El2CE:4=6\agd`agQm%96 (6DE’D :4@?:4 7@C6DED 2C6 :?4C62D:?8=J DECF88=:?8 E@ C64@G6C 7C@> H:=57:C6D – 2=E6C:?8 9@H 7:C6D 3FC? 4@F=5 3@@DE E96:C 492?46Dk^2mk^6>mk^=:m
kA 4=2DDlQ7:?6\AC:?EQmk6>mk6>mkDA2?ms>:EC: z2=2D9?:<@G C646:G6D 7F?5:?8 7C@> E96 }2E:@?2= $4:6?46 u@F?52E:@?]k^DA2?mk^6>mk^6>mk^Am
kA 4=2DDlQ7:?6\AC:?EQmk6>mkDA2?m|259F=:<2 vFC2K252 C646:G6D 7F?5:?8 E9C@F89 E96 u2C>D u@@5 uFEFC6 x??@G2E:@? x?:E:2E:G6[ DFAA@CE65 3J E96 &]$] s6A2CE>6?E @7 r@>>6C46VD t4@?@>:4 s6G6=@A>6?E p5>:?:DEC2E:@? qF:=5 q24< q6EE6C #68:@?2= r92==6?86]k^DA2?mk^6>mk^Am
kA 4=2DDlQ7:?6\AC:?EQmk6>mkDA2?mr@?8 *:? 2?5 |F<6D9 zF>2C 5@ ?@E H@C< 7@C[ 4@?DF=E[ @H? D92C6D :? @C C646:G6 7F?5:?8 7C@> 2?J 4@>A2?J @C @C82?:K2E:@? E92E H@F=5 36?67:E 7C@> E9:D 2CE:4=6[ 2?5 92G6 5:D4=@D65 ?@ C6=6G2?E 277:=:2E:@?D 36J@?5 E96:C 24256>:4 2AA@:?E>6?E]k^DA2?mk^6>mk^Am
kAmk:>8 DC4lQ9EEADi^^4@F?E6C]E964@?G6CD2E:@?]4@>^4@?E6?E^agd`ag^4@F?E]8:7n5:DEC:3FE@Cl=66Q DEJ=6lQ96:89Ei`AIjH:5E9i`AIjQ 2=ElQQ ^mk^Am
(0) comments
Welcome to the discussion.
Log In
Keep it Clean. Please avoid obscene, vulgar, lewd, racist or sexually-oriented language.
PLEASE TURN OFF YOUR CAPS LOCK.
Don't Threaten. Threats of harming another person will not be tolerated.
Be Truthful. Don't knowingly lie about anyone or anything.
Be Nice. No racism, sexism or any sort of -ism that is degrading to another person.
Be Proactive. Use the 'Report' link on each comment to let us know of abusive posts.
Share with Us. We'd love to hear eyewitness accounts, the history behind an article.