Graph 1 shows how cyclical changes in the Sun caused predictable changes in the solar intensity reaching Earth’s atmosphere. Graph 1 also shows how much the global surface temperature has moved from the long-term average. Graph 2 shows observations of global temperature (black line). The blue line is a temperature model where only natural forces, such as volcanic eruptions, are considered. The red line is a temperature model of both natural forces and human effects (activities). Study the graphs, and answer the questions that follow. Graph 1 a graph showing a constant gradual rise in global temperatures since 1980 and a graph showing that the amount of the Sun's energy reaching the atmosphere has risen and fallen regularly since 1980 Graph 2 a graph showing the observed changes in average global temperature, a temperature model that considers the effect of natural forces on temperature change, and a temperature model that considers both natural and human effects on temperature change Part A

Based on graph 1, do you think the changes in solar intensity are a significant cause of the trend in global temperatures? Why or why not?