The illustration depicts a man-made process in which food is cooked using a solar box oven.
Overall, this six-step linear process begins with painting the cardboard box black, followed by placing a pot with vegetables inside, and ends with putting the setup under direct sunlight at a minimum temperature of 82°C.
First, a cardboard box is painted black in order to absorb sunlight. Once this step is completed, a pot is filled with vegetables. Afterward, the pot is put inside the painted cardboard box to prepare it for the heating process.
Next, the smaller box containing the pot is put into a larger box, and the bottom of this box is lined with insulating materials such as newspaper, grass, or sawdust. Then, the top of the larger box is covered with foil and a glass lid is placed on it to trap heat. Finally, the entire setup is positioned under direct sunlight with a minimum temperature of 82°C, where the black surface is used to absorb and convert sunlight into the heat, allowing food to be cooked.