From the Source:
"Global warming will alter fire regimes. Climate models predict that higher temperatures and longer droughts will increase wildfire frequency, particularly in semi-arid regions. Higher rainfall in some areas could reduce fire frequency, though it could also foster more vegetation, thus providing more fuel for fires. Lightning, an important ignition source, is thought to increase in a warmer climate, and more-intense rainstorms could exacerbate post-fire runoff and landslides. Fire is expected to grow as a source of carbon dioxide."