Inter-annual variation of the earth rotation and El Niño

The relationship between the inter-annual variations of the earth rotation, atmospheric angular momentum (AAM), sunspot number and El Niño is analyzed. The result shows that the inter-annual variation of the earth rotation responds to the variation of AAM and the pregnancy of El Niño timely. Generally, the inter-annual component of the earth rotation will reach zero in a changing process that increases from the negative to the positive extreme before El Niño occurs about half year or more. And the solar activity may have certain influence on the appearance of El Niño. We consider that El Niño will possibly appear around the end of 2001.