Photo by Scott Rowland. Arenal is a stratovolcano in Costa Rica that has been very active in recent years. An eruption in 1968 wiped out the town of Pueblo Nuevo, killing 78 people. The volcano has produced loud explosions, gas clouds, ash and vapor, and lava flows frequently since the 1968 eruption. Arenal's last major eruption occurred in 1993.
On 24-25 March, pyroclastic flows traveled down the N and NE flanks of the Arenal volcano. The resulting ash clouds deposited ash on an area up to 10 km2. Some of the block and ash deposits were several meters thick and the debris fan was ~250 m wide. There were no reports of injuries or damage to structures.
On 23 August, the Arenal Volcano erupted killing one person and injuring two others. The volcano erupted a sequence of pyroclastic flows orginated by a crater collapse in the north flank of Arenal. The deposits reached a maximum distance of 2.7 km from the active crater and expanded more than 300 m in the distal part. The National Park was closed and most of the hotels in the area were evacuated.
Arenal erupted rock and ash high into the air on May 5. This explosive eruption split the crater, spilling lava down the north slope of the volcano. Rocks were ejected from the volcano at speeds of 120 miles per hour. A red alert was declared, and 450 people were evacuated due to dangers of flying debris and lava flows. No casualties were reported, and damage was minimal. This was the largest eruption since 1993.
The pyroclastic flows discharged by Arenal in the eruption of May 5 traveled several kilometers down the northwest flank of the volcano. Ash fell at least as far as ~3 miles (~5 km) from the now partially collapsed crater.