How to prove anthropogenic global warming?

For example, you can compare the results of two climate models: one - greenhouse gases produced by humanity, and another without them. At the same time it turns out, what role in warming is played by natural factors: solar activity, volcanic eruptions, etc.

With regard to atmospheric warming, most scientists long been clear that for him responsible people. But in the World ocean, this method is still used very carefully. Meanwhile, about 90% of the energy captured greenhouse gases in the atmosphere, in the end turns out to be just in the water, not in the air. The heat capacity of the ocean really grows; it remains to be seen whether it is connected with the natural processes.

An international group of researchers collected the results of a number of climate models and compared them with the temperature reading upper 700m of the ocean in the period from 1960 to 1999. For deeper waters, the data are less complete, and besides, there's response to climate change is not so noticeable. In addition, the researchers analyzed each of the major basins (North and South Atlantic, the North and the South Pacific ocean, the same part of the Indian) separately.

It turned out that in observational data anthropogenic "fingerprints" are 99% probability. In other words, the degree of warming beyond natural variability, which gives the model with constant levels of greenhouse gases. A model in which people are changing the composition of the atmosphere, predict exactly what is happening.

For climatologists in these findings is not surprising. Much more interesting differences between marine basins. The Atlantic ocean is warming up faster than the others, especially in the Northern part, where warming is about two times higher than the average rate. This situation is also predicted by the models.

This is not the first study that found anthropogenic trace in the temperature of the World ocean. But previous work was limited private pools or small set of climate models.

The study is published in the journal Nature Climate Change.

Prepared according to Ars Technica.