Scientists examine temperature and salinity of sea water with device CTD onboard ship Xiangyanghong 09 in the South China Sea, south China, April 25, 2017. Chinese scientists embarked on a deep-sea mission in the South China Sea on Tuesday, the beginning of the second stage of China's 38th oceanic expedition. China's manned submersible Jiaolong with her crew of scientists arrived in the location aboard the mother ship Xiangyanghong 09. The submersible is expected to conduct its first South China Sea dive this year on Wednesday. (Xinhua/Liu Shiping)