In the best-case scenario, in 2030 the impact of the changes in the on international trade that passes through three strategic sea arteries (chokepoints), i.e. the Panama, the Suez Canal and the Turkish Straits, will cause a reduction of up to $34 billion (2014 prices) of world gross domestic product. This is highlighted by a study led by the Euro-Mediterranean Centre on Climate Change (CMCC) focuses on the effects of this impact on production and agricultural commodity prices.

The value of these additional costs has been estimated on the basis of the basis of an SSP3 scenario in terms of socio-economic pathways Shared Socioeconomic Pathway, which assumes an evolution of the of the world economy, which has a lower degree of international trade cooperation due to fears about the food security and energy dependence.

The study points out that macroeconomic losses resulting from restrictions imposed by the effects of climate change on the Three sea routes are negligible in terms of variation percentage and range from -0.02% of world GDP in the case of the channel -0.004% in the case of the Suez Canal and -0.002% in the case of the Suez Canal. case of the Turkish Straits. These are product reductions global gross domestic - the study specifies - which are mainly borne by importers (80% of the total).

The study also finds that, in a scenario fragmented by the socio-economic point of view such as SSP3, the effects of the reduction in ship traffic in these three primary maritime arteries are heavier than an SSP2 scenario with an average level of openness international trade.

Focusing on the assessment of the impact of changes climate change on the three crucial maritime routes, the study explains that the Restrictions on ship traffic in the Panama Canal appear to be the most critical ones, giving rise to the most critical macroeconomic impacts at the global level and for different groups of countries: exporters, the document specifies, the United States and Canada they are clearly the losers to Ukraine and India; the EU area also responds with increases in agricultural production and exports, but nevertheless recorded an overall GDP growth slightly negative; All importers register a decline in imports, particularly acute in China for seeds oily oils, in the MENA region for wheat and in South Korea for other cereals.

Restrictions on commercial traffic through the Suez Canal - the study continues - they tend to penalise Ukrainian, Russian and partly Indian exports, favoring the USA, Argentina, Australia, Brazil and Paraguay. The Decline of imports is particularly evident in the MENA region, in sub-Saharan Africa and in the "Tigris and Euphrates". The impacts on the EU are particularly evident increasing rice production.

Restrictions on the commercial traffic in the Turkish Straits, on the other hand, have the largest negative impacts on Russia and Ukraine, whose exports of grains are mostly transported via this route while they tend to favour other exporters such as Argentina (other cereals), India (wheat and other cereals), Brazil (of other cereals), the United States (of wheat and other cereals) and Canada (wheat). The EU responds by increasing the production and export of wheat and decreasing that of rice. Within the EU area, there is also a substitution between the cereal producers in the Mediterranean and Eastern Europe. A Particularly worrying decline in commodity imports This is particularly affecting Turkey, the MENA region, the of the Tigris and Euphrates as far as wheat is concerned, and China.

With regard to the economy of the European Union alone, the notes that weather events in localities remote from this market such as the Panama Canal, which It is currently the most affected maritime artery by the lack of precipitation, could have a negative impact on the cascading to the EU with potential losses of €2 billion dollars of GDP. The study points out that even more The impact on low- and middle-income countries is worrying: The study shows that North Africa, the Middle East and the sub-Saharan Africa are even more vulnerable to these effects, once again highlighting the asymmetry and unequal distribution of climate change impacts on agriculture.

The study concludes that the MENA area, the Tigris area and the of the Euphrates and the area of sub-Saharan Africa could be particularly vulnerable to climate change, including as a result of the restrictions on commercial traffic that could affect three maritime chokepoints. In all three cases, the three areas would suffer from a decline in imports of agricultural products whereas, although the absolute values of the decline would be modest, they are However, they should be considered worrying, also in view of the fact that many of the countries affected are middle- and low-income. In addition, the negative impacts would be in addition to the reduction of harvested in those regions caused by climate change.