*3.4. Performance of SM2RAIN-CCI and SM2RAIN-ASCAT in Detecting Precipitation Events*

Table 6 shows the daily scale averaged regional categorical metrics of SM2RAIN-CCI and SM2RAIN-ASCAT during a common period of 2007–2015. The categorical metrics are calculated by using a threshold of 1 mm/day. Higher POD (lower FAR) values were detected in the hyper-arid region. The humid region has a lower POD (higher FAR) because of high precipitation magnitude and intensity in the region. Moreover, saturated soil and water storage in hydraulic structures might be the cause of lower POD (higher FAR) in the humid region. Similarly, CSI and the bias score (BS) was also higher in the hyper-arid region and lower in humid region. About the skill of detecting precipitation events, SM2RAIN-ASCAT outperformed SM2RAIN-CCI across three climate regions of Pakistan. In terms of

POD (FAR), SM2RAIN-ASCAT improved the precipitation detection capability by 11.94% (15%) in humid, 10.67% (14.28%) in arid and 8.53% (19.05%) in hyper-arid regions.


**Table 5.** Seasonal evaluation of SM2RAIN-ASCAT across Pakistan during 2007-2015.

**Table 6.** Daily scale averaged regional categorical metrics of SM2RAIN-CCI (SM2RAIN-ASCAT) during 2007–2015.

