Precipitation

1. Compare Change of Annual Precipitation

Analyzed Trend is +3.15mm higher in Seonbong than Seogwipo.

The change of heavy rain days is +0.252087days greater in Seogwipo than Seonbong.

2, Compare Change of Seasonal Precipitation

Spring

Analyzed Trend is +0.95391868mm higher in Seogwipo than Seonbong.

Summer

Analyzed Trend is +7.65354169mm higher in Seonbong than Seogwipo.

Autumn

Analyzed Tred is +18.7868055mm higher in Seogwipo than Seonbong.

Winter

Analyzed Trend is +4.56124998mm higher in Seogwipo than Seonbong.

3. Compare Annual Sum of Precipitation

When drawing a graph of the annual sum of precipitation data of Seogwipo and Seonbong, we found out that some values were located without periodicity. We thought these outliers could have been caused by a typhoon-like weather phenomenon. So we used the quartile concept to sort out the outlier in a climatic statistical way.

Firstly we got quartile values Q1(25% value) and Q3(75% value), and obtained InterQuartile range, IQR(Q3-Q1). Using these values, we obtained the upper fence (Q3+1.5*IQR) and lower fence (Q1-1.5*IQR). A value greater than the upper fence and a value lesser than the lower fence was set as the outlier(special case).

Red points are special cases.

In Seogwipo annual sum of precipitation data, the average was 1912.198mm, IQR: 541.325, upper fence: 2996.25mm and lower fence: 830.97mm. The ranges x > 2996.25mm and x<830.97mm were set as special cases. As a result, 1985 was set as a special case, with annual sum of precipitation, 3244.3mm.

In Seonbong annual sum of precipitation data, the average was 677.8848mm, IQR: 274.775, upper fence: 1211.713mm and lower fence:112.612mm were obtained. The ranges x>1211.71mm and x<112.613mm were set as special cases. As a result, 2015 with an annual sum of precipitation,1550.9mm, was set as a special case.

In the data for the difference in Seogwipo & Seonbong annual sum of precipitation, the average was 1234.313mm, IQR: 572.775, upper fence: 2333.213mm and lower fence: 42.1125mm. The ranges x>233.21mm and x<21.1125mm were set as special cases. As a result, the special cases were set in 1985 with a difference of 2,787.9 mm and 1999 with a difference of 2,349.3 mm.

1. Seogwipo's Special case, 1985

1985.06.20~1985.07.21 : Assumed Rainy season(KMA, 장마백서2011)

Total precipitation on rainy season : 1342.8mm

Special cases

1985.06.22 precipitation : 143.5mm
1985.06.24 precipitation: 137.2mm
1985.06.26 precipitation : 232.8mm
1985.06.27 precipitation : 144.2mm
1985.06.28 precipitation : 96.3mm
1985.07.03 precipitation : 72.9mm
1985.07.04 precipitation : 218mm
1985.07.05 precipitation : 187mm

Total precipitation
: 1,231.9mm

1985.08.09~1985.08.11 : Typhoon KIT

Main day's precipitation of this typhoon : 232.4mm

2. Seonbong's Special case, 2015

2015.05.12. precipitation: 49mm
reason: effect of the lower pressure located in Eastern China

2015.05.27. precipitation: 33mm
reason: effect of the higher pressure located in West sea

2015.07.13. precipitation: 96mm
reason: effect of the 9th typhoon CHAN-HOM moving northern

2015.08.14. precipitation: 58mm
reason: Located at the edge of a high pressure on the west coast

2015.08.16. precipitation: 361mm
reason: Located at the edge of a high pressure on the west coast & Influence of low pressure trough

and mild high pressure passing through the Northern Region

2015.08.21. precipitation: 353mm, 2015.08.22. precipitation: 100mm
reason: influence of weak pressure trough passing northward

2015.10.01. precipitation: 115mm
reason: Influence of low pressure

2015.10.08. precipitation: 38mm
reason: Located at the edge of a high pressure on the west coast and the influence of pressure trough

gradually approaching from the northwest