Anshari et al. 2004; Anshari et al. 2010), <100 mm of rainfall occurred during the
dry months. The dry season usually occurred between July and August in both
concessions. A short and weak dry season often occurred from January to February.
Since there was only one station from 2009 to 2011, the average annual rainfall
between 2012 and 2019 was calculated to examine annual changes (Fig. 3.26). In
2014 and 2015, an apparent decrease in total rainfall was observed. Although the
2 years of lower rainfall showed the same (approximately 2500 mm/year) total
rainfall, the completely rainless period each year differed markedly, i.e., 50 days
in 2015 and 27 days in 2014. Almost no rain fell for 100 days from June to
September 2015. The long drought caused by a strong El Niño event in 2015
triggered large-scale forest and peat fires throughout Indonesia.
Fig. 3.26 Annual rainfall (mm) in WSL-MTI from 2012 to 2019. Annual rainfall was calculated as
the average of seven stations
Fig. 3.25 The seasonal rainfall pattern in WSL-MTI from 2012 to 2019
3 Large-Scale Practice on Tropical Peatland Eco-Management
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