Abstract
The study aims to investigate the relationship between dominant climate
variabilities namely El Niño-Southern Oscillation (ENSO), and Indian
Ocean Dipole (IOD) versus rainfall, and vertical humidity in Chiangmai,
Thailand. The Oceanic Niño Index (ONI) which represents ENSO status and
Dipole Mode Index (DMI) which represent IOD indicator were collected for
the period 1986-2020 (35 years). Subsequently, the 12-month lag
correlations were analyzed between both indicators against rainfall and
vertical moisture at cloud-base and cloud-top height levels for the same
time periods. The results indicate that the impacts of both climate
variabilities may not occur during the same period of the phenomenon.
The effects of ENSO to weather pattern in Chiang Mai might be lagged by
0 to 12 months. Even though the correlation of the humidity versus ONI
and DMI is fluctuated. The correlation results of ONI and cloud-base
humidity level has moderate values and consistent with La Niña events.
However, the DMI correlations against rainfall and mixing ratio are
inconclusive due to insufficient data. The relationship between ONI
index, rainfall, and mixing ratio can be used to predict the future
rainfall and atmospheric moisture once they are validated. Keyword:
ENSO, ONI, DMI, IOD, rainfall, mixing ratio, vertical humidity