Poas – stratovolcano, Costa Rica

Eruption history

VEI – Volcanic Explosivity Index: 0 = lava outpouring, 4 = like Eyjafjallajökull 2010, 6 = like Pinatubo 1991, 7 = like Tambora 1815. The scale is logarithmic – each step is about 10 times more material.

Start	End	VEI	Vent and dating
5 January 2025	continuing	2	Observations: Reported
1 December 2023	5 May 2024	1	Observations: Reported
2 August 2023	11 August 2023	1	Observations: Reported
6 April 2022	6 April 2022	1	Crater lake - Fumarola Naranja · Observations: Reported
7 February 2019	30 September 2019	2	Caliente Summit Crater · Observations: Reported
25 May 2018	25 May 2018	?	Summit crater · Observations: Reported
12 April 2017	6 November 2017	1	Laguna Caliente Crater · Observations: Reported
5 June 2016	16 August 2016	1	Lake in summit crater · Observations: Reported
16 November 2009	13 October 2014	1	Observations: Reported
12 January 2009	21 March 2009	1	Observations: Reported
13 January 2008	13 January 2008	1	Observations: Reported
25 September 2006	16 December 2006	1	Observations: Reported
24 March 2006	24 March 2006	1	Observations: Reported
8 April 1996	8 April 1996	1	Observations: Reported
16 March 1994	16 October 1994	2	Observations: Reported
16 October 1992	16 September 1993	0	Observations: Reported
16 February 1992	16 March 1992	1	Observations: Reported
6 March 1991	16 September 1991	1	Observations: Reported
16 June 1987	16 June 1990	2	Observations: Reported
16 March 1981	16 May 1981	1	Observations: Reported
26 December 1980	26 December 1980	1	Observations: Reported
12 September 1980	12 September 1980	1	Observations: Reported
8 September 1979	16 January 1980	1	Observations: Reported
22 September 1978	16 December 1978	1	Observations: Reported
18 December 1977	15 June 1978	2	Observations: Reported
16 May 1977	16 July 1977	1	Observations: Reported
21 June 1976	16 November 1976	2	Observations: Reported
11 September 1974	16 February 1975	2	Observations: Reported
9 February 1972	8 September 1973	2	Observations: Reported
16 July 1970	—	1	Observations: Reported
3 May 1969	3 June 1969	2	Observations: Reported
2 July 1968	—	1	Observations: Reported
1 January 1967	—	1	Observations: Reported
25 December 1964	16 March 1965	2	Observations: Reported
23 May 1963	2 July 1963	2	Observations: Reported
2 July 1958	3 July 1961	2	Observations: Reported
23 March 1952	25 December 1957	2	Observations: Reported
2 July 1948	2 July 1951	1	Observations: Reported
4 November 1946	—	1	Observations: Reported
2 July 1941	2 July 1946	1	Observations: Reported
2 July 1932	2 July 1934	1	Observations: Reported
2 July 1929	—	1	Observations: Reported
2 July 1925	—	1	Observations: Reported
2 July 1916	—	2	Observations: Reported
8 October 1914	15 May 1915	2	Observations: Reported
30 May 1914	—	2	Observations: Reported
12 September 1910	14 October 1910	1	Observations: Reported
25 January 1910	16 February 1910	2	Observations: Reported
29 December 1898	31 December 1907	1	Observations: Reported
2 July 1895	—	1	Observations: Reported
16 January 1888	2 July 1891	1	Observations: Reported
2 July 1880	—	1	Observations: Reported
2 July 1860	—	1	Observations: Reported
2 July 1834	—	2	Observations: Reported
2 July 1828	—	1	Observations: Reported
1747	—	2	Observations: Reported
c. 1280	—	?	North flank (Bosque Alegre) · Correlation: Tephrochronology
c. 210	—	?	North flank (Bosque Alegre) · Correlation: Tephrochronology
760 BCE ± 200 years	—	?	North flank (Bosque Alegre) · Isotopic: 14C (calibrated)
c. 3,950 BCE	—	?	North flank (Cerro Congo) · Isotopic: 14C (calibrated)
5,590 BCE ± 100 years	—	?	Botos Cone · Isotopic: 14C (uncalibrated)
7,620 BCE ± 100 years	—	?	Isotopic: 14C (uncalibrated)
7,920 BCE ± 75 years	—	?	Isotopic: 14C (uncalibrated)

Data: Global Volcanism Program, Smithsonian Institution (#345040)