The current eccentricity of Earth is .017. The shape of the Earth's orbit changes from being elliptical (high eccentricity) to being nearly
circular (low eccentricity) in a cycle that takes between 90,000 and 100,000 years. When the orbit is highly elliptical, the amount of
insolation received at perihelion would be on the order of 20 to 30 percent greater than at aphelion. What would be the predicted
result of this change?

The awnser is “A much warmer climate than what we are currently experiencing”

In the given case, a much warmer climate will be experienced in comparison to what one is experiencing at the present time.

Explanation:

When the orbit of the Earth changes its path, one can witness a variation in the Earth's climatic conditions. Like when the Earth comes nearer to the Sun, the climate of the Earth becomes warmer. However, when the axis of the Earth shifts slightly away from the Sun, one can witness a reduction in the Earth's temperature.  

Therefore, in the given case, the isolation received at perihelion would be twenty to thirty percent more in comparison to aphelion when the orbit is more elliptical, this condition eventually results in a warmer climate.