Australia Weather News

A few weeks ago, the World Meteorological Organisation issued a statement on the status of the world's climate indicating 2015 "will make history for a number of reasons".

Even before December figures are available, it is certain that – worldwide – 2015 will be the warmest year since records commenced and that the 5 year period 2011-2015 also expected to be the warmest 5 year period ever, with the surface temperatures reaching the significant milestone of 1°C above the pre-industrial levels (1850-1900) for the first time.

Climate scientists believe the combination of carbon emission along with the impact of the strongest "El Nino" in almost 20 years has been the cause of this significant result. The "El Nino" event is a natural fluctuation in the world's weather patterns, especially in the Pacific and many such events have occurred previously so it is clear there must be other factors contributing to the current situation.

If the world continues to warm in the coming decades, there is likely to be more years exceeding to 1 degree threshold but there are also indications that an increased variability will become more likely. The concerning factor at the moment, however, is that it appears likely that the world is now half way towards the 2°C mark which many scientists believe is the "gateway" to a dangerous level of warming.

The warmth of 2015 follows 2014 which was the warmest year on record. The "El Nino" event will fade away in the early part of 2016 so it is possible that 2016 might not be quite as warm, worldwide. 2015 was also significant for the levels of greenhouse gases. New record high levels were set in the northern hemisphere in their spring and the 3 month global average concentration of carbon dioxide exceeded 400 parts per million for the first time on record.