“…tic conditions at those sites. It is very difficult, however, to create a complete data set for driving a model solely from observations, which are prone to data gaps due to instrument problems, human mistakes, or other reasons (Nakai et al, 2013;Kodama et al, 2007;Watanabe et al, 2000;Iwahana et al, 2014;Ohta et al, 2001Ohta et al, , 2008Ohta et al, , 2014Kotani et al, 2013;Lopez et al, 2007;Nakai et al, 2008;Sato et al, 2001). Despite efforts to maintain and improve our observational network, data gaps are unavoidable, as the availability of instrumentation is often limited by logistical or funding issues.…”