Source: China Business Daily
On March 12, 2015, climate scientists at the US National Oceanic and Atmospheric Administration (NOAA) officially reported in the latest Technical Bulletin that El Nino event has arrived once again, and 2015 would likely be the warmest year ever measured globally.
El Nino strengthens the global warming
According to US media reports, scientists outlined their decision process in an official blog post.
According to the blog of NOAA, in the past few months, scientists observed the all-time highest average sea surface temperature in the tropical Pacific. The objects of observation include the sea surface temperature within Nino 3.4 region, which is considered to be an indicator of the occurrence of the EI Nino phenomenon. The seasonal Nino 3.4 index increased by more than 0.5℃ since last September. The Nino 3.4 index increased by more than 0.6℃ in recent weeks.
In addition, the atmospheric conditions observed by scientists also indicate that El Nino is occurring. Therefore, after the predication for a few months, NOAA has officially announced the arrival of El Nino, which will certainly make the gradually warming world become even hotter.
The duration of this year may be longer
El Nino will transfer the huge amounts of heat from the ocean to the atmosphere. So, it can be imagined that the trend of global warming will probably become intensified, if El Nino of this year combines with the gradually warming global oceans. An associated slow-moving indicator, PDO index（The Pacific Decadal Oscillation, i.e. Pacific Decadal Oscillation Index, also called as "Lamadre" phenomenon）also reached a record level in December last year and January this year.
Should the PDO stat strong, it will essentially join force with the El Nino, and thus 2015 will rank as the warmest year on record globally.
Typical El Nino only lasts 6-8 months. However, the duration of El Nino in this year may increase to two years or more.
Threats to China's grain production
Steve Zebiak, a Columbia University climate scientist, who helped issue the first successful prediction of El Nino in 1985, says, if as currently predicted, El Nino in this year continues to strengthen, 2015 would likely be the warmest year ever measured globally.
In general, El Nino may lead to the postponement of the rainy season in southern China. El Nino will bring about continuous rainfall to the south, leading to droughts in the north and floods in the south. Zheng Dawei, a professor of resources and environmental sciences, China Agricultural University says that the occurrence of El Nino event will pose a threat to China's grain production and more attention is needed. "The reduction of our food production were caused by some El Nino years in the history, mostly appeared in the same year and also in the second year, this is related to the seasonal occurrence of El Nino".