Annual food production in Ancient Egypt was completely dependent on .

Annual food production in Ancient Egypt was completely dependent on annual flood level of the Nile river.

Explanation:

Water is one of the most important sources for the growth of the crops and for agricultural activities including other important sources such as the nutrition level of the soil, the temperature of the area, the availability of sun light and so on.

Since Egypt is a lot dependent n the Nile river for it's activities of life, the flood level of the same river decided the growth and the production of the agriculture of the country.

it is very hard for the climatologists to precisely predict how will the global temperatures be changing so there's lots of models, some of which differ significantly, this is due to multiple factors, and probably the most important is the human activity.

humans have been a key factor in climate change around the globe since the start of the industrial revolution, and in the past few decades the consequences are becoming more obvious. there's lots of emission of pollutants in the atmosphere as well as changing the environment on the surface itself, so it's really hard to predict how will that go in the future because there's some countries that are reducing the damage and are going towards green energy, while others are stubbornly continuing with pollution and damages to the environment.