Table 3.

Isoprene and monoterpenes (sum of α-pinene, β-pinene, limonene, and 1,8-cineole) surface emission rates per vegetation type. Miscellaneous refers to a mix of different species, including lichens and moss tundra (see Figs. S3–S15). Daytime refers to 10:00–20:00, midday to 11:00–14:00, and nighttime to 23:00–05:00 (Alaska standard time – UTC−9). The values in parentheses represent the average enclosure temperature for each emission rate.

	Mean ± standard deviation (μgC m−2 h−1)	Daytime mean ± standard deviation (μgC m−2 h−1)	Midday mean ± standard deviation (μgC m−2 h−1)	Nighttime mean ± standard deviation (μgC m−2 h−1)
Isoprene
Salix spp.	149 ± 327 (17.6 °C)	232 ± 400 (23.9 °C)	334 ± 473 (27.0 °C)	7 ± 10 (8.0 °C)
Betula spp.	12 ± 30 (13.7 °C)	19 ± 38 (17.4 °C)	28 ± 37 (20.1 °C)	5 ± 14 (5.8 °C)
Miscellaneous	38 ± 81 (11.8 °C)	57 ± 100 (14.8 °C)	104 ± 135 (16.2°C)	21 ± 64 (8.2 °C)
Monoterpenes
Salix spp.	0.8 ± 1.3 (17.6 °C)	1.1 ± 1.5 (23.9 °C)	1.4 ± 1.7 (27.0 °C)	0.4 ± 1.0 (8.0 °C)
Betula spp.	0.5 ± 0.6 (13.7 °C)	0.7 ± 0.7 (17.4 °C)	1.0 ± 0.8 (20.1 °C)	0.2 ± 0.2 (5.8 °C)
Miscellaneous	1.1 ± 1.4 (11.8 °C)	1.3 ± 1.6 (14.8 °C)	1.7 ± 2.0 (16.2 °C)	1.0 ± 1.4 (8.2°C)