Temperature Variability and Trends Assessments parts of Highland and Momase region of Papua New Guinea

Abstract

Mean temperature trend investigation was carried out for the provinces in the highlands region to coastal regions of the country Papua New Guinea (PNG). The assessment encompasses ways forward to figure out how temperature varies over time including the direction and magnitude of trend, which is either increasing or decreasing at certain magnitude level. Temperature trend and or variability investigation was carried out for 50 years time period, starting 1968 all the way to 2018. Parametric and non-parametric Mann-Kendal and Sen’s statistics including ArcGIS spatial statistics were used to investigate trend both on spatial and temporal basis. The trend was investigated within the study region on both annual and seasonal basis. The CRU TS 4.03 gridded mean temperature (TMP) data sets on a spatial resolution of 0.5⁰ by 0.5⁰ were used to investigate temperature trend including temperature mean over time. Total of 57 stations were generated from the gridded data. The assessment and analysis were carried out for each station (STN 1 – 57) and the results are both presented graphically and spatially with written documents. Within the study region either annual or seasonal, majority of stations show increasing trend rather than decreasing trend. Most of the stations displayed significant increasing/decreasing trend over 50 years time period. The overall temperature trend for the study region was investigated and calculated to be significantly increasing at 0.01 ⁰C/year. On monthly average, the month of June, July, August and September are observed to experience medium to low temperature and month of November, December, January , February and March were observed to be experiencing medium to high temperatures.