Earth's surface is primarily warmed by the process of solar radiation absorption and the subsequent emission of infrared radiation. This process, known as the greenhouse effect, plays a crucial role in regulating the planet's temperature.

Here's how it works:

As a result of the greenhouse effect, the Earth's surface is heated, creating a habitable temperature range for life as we know it.

Regarding the layer of the atmosphere where molecules have enough energy to escape, it is the exosphere. The exosphere is the outermost layer of the Earth's atmosphere, extending from about 500 kilometers (310 miles) above the Earth's surface and gradually transitioning into space. In the exosphere, gas molecules, primarily hydrogen (H) and helium (He), have enough kinetic energy to overcome the gravitational pull of the Earth and escape into space.

The exosphere is characterized by extremely low densities, and it is where the Earth's atmosphere gradually merges with the vacuum of outer space. Gas molecules in the exosphere are in constant motion, and some of them reach escape velocity due to their high kinetic energy, allowing them to dissipate into space. It's important to note that the exosphere is so thin that it contains very few gas molecules, and interactions between these molecules are infrequent. This makes it very different from the denser layers of the atmosphere closer to the Earth's surface.

Dr Gaurav H Tandon thank you for your contribution to the discussion

Earth's atmosphere keeps much of the Sun's energy from escaping into space. This process, called the greenhouse effect, keeps the planet warm enough for life to exist. The atmosphere allows about half of the Sun's heat energy (50%) to reach Earth's surface. This is the outermost layer of the atmosphere. It extends from about 375 miles (600 km) to 6,200 miles (10,000 km) above the earth. In this layer, atoms and molecules escape into space and satellites orbit the earth. The general thermal energy of the atmospheric gas ultimately comes from, e.g., absorbed stellar radiation or from heat leaking out of the interior of the planet. No thermal escape mechanisms. Here, a “collision process” energizes gas species above the escape barrier. The energy that Earth receives from sunlight is balanced by an equal amount of energy radiating into space. The energy escapes in the form of thermal infrared radiation: like the energy you feel radiating from a heat lamp. Due to thermal mechanisms, a lighter molecule is more likely to escape from the atmosphere because of its higher average speed at a given temperature. For example, hydrogen escapes more easily than carbon dioxide. This has numerous applications in astrophysical and planetary science.Barring a large asteroid impact that can inject large swaths of the atmosphere into space, the only gases that regularly escape Earth's atmosphere today are hydrogen and helium, the lightest elements in the universe. There are several ways hydrogen and helium molecules can wind up on a one-way mission to space.Atmospheric radiation is the flow of electromagnetic energy between the sun and the Earth's surface as it is influenced by clouds, aerosols, and gases in the Earth's atmosphere. It includes both solar radiation (sunlight) and long-wave (thermal) radiation. The greenhouse effect causes some of this energy to be waylaid in the atmosphere, absorbed and released by greenhouse gases. Without the greenhouse effect, Earth's temperature would be below freezing. It is, in part, a natural process. Process of warming of planet's surface and its lower atmosphere by the absorption of infrared radiations of long wavelength given out from the surface of a planet is known as green house effect. The greenhouse effect is the way in which heat is trapped close to Earth's surface by “greenhouse gases.” These heat-trapping gases can be thought of as a blanket wrapped around Earth, keeping the planet toastier than it would be without them. The atmosphere of the earth is heated by the process of convection. In cases of liquids and gases, the transfer of heat takes place through convection. It is a process by which heat travels through water, gas, air, or other liquids. The greenhouse effect happens when certain gases known as greenhouse gases collect in Earth's atmosphere. These gases, which occur naturally in the atmosphere, include carbon dioxide, methane, nitrogen oxide, and fluorinated gases sometimes known as chlorofluorocarbons (CFCs). Conduction is a slow process of heat transfer as regards warming of the atmosphere. Since air is a very poor conductor of heat, the conduction process affects only the lowermost layers of air closest to the earth's surface.