Anthropogenic Ignition and Fire Weather Extremes: An Assessment of Meteorological Extremes Preceding the 2023 Central Western Ghats Forest Fire.

In March 2023, a record area of 418 hectares was burnt in forest fires across the Goan region of the Central Western Ghats(CWG). We investigated the causes of this sudden forest fire using live meteorological and phenological datasets collected before, during, and after the incident from our PhenoMet tower located in the Netravali Wildlife Sanctuary (WLS) in the CWG. The farmers of forest fringes used conduct controlled burning on their farm, which sometimes results in minor forest fires. In 2023, this activity gone out of control and led to unprecedented forest fires. The State forest department reports that the fire occurred between 4^th to 15^thMarch 2023. A review of literature suggests that the fire weather conditions are generally associated with prevalence of > 28⁰c mean daily temperatures, <40% daily mean humidity, and, > 38⁰c maximum daily temperature, and > 25⁰c daily minimum temperature. We found that the onset of the forest fire on March 4 marked with a maximum temperature exceeding 37°C, a mean daily temperature above 28 °C, and a daily average humidity of 27%, with a minimum of 13%. The fire weather conditions initiated on February 22 and persisted until March 15, lasting for 22 days. While the onset of the forest fire was associated with low humidity values along with other weather parameters, the dousing of fires was associated with a notable increase in humidity values. We noted a perceptible change in the weather parameters close to March 15 with the Daily Average Humidity values rising from below 63% to close to 82% in 24 hours. While the Max Humidity showed only a slight increase from 96% to 98%, the Minimum Humidity values rose from 25% to 38%. Also, advancing the End of Season and shortening growing seasons in The Tropical Semi Evergreen Forest increased fire susceptibility. This study provides insight into the weather parameters that escalate forest fires.It will contribute to improving forest fire management and reducing the impact of future fire events especially in rich biodiversity areas such as the tropical evergreen and the semi-evergreen forest of Western Ghats