The increasing atmospheric concentration of carbon dioxide CO2 affects the absorption and emission of infrared radiation in several ways, ultimately contributing to the enhanced greenhouse effect and global warming.1. Absorption of infrared radiation: CO2 is a greenhouse gas, which means it has the ability to absorb infrared radiation emitted by the Earth's surface. When the concentration of CO2 in the atmosphere increases, more infrared radiation is absorbed by the gas molecules. This absorption of infrared radiation by CO2 molecules causes them to vibrate and gain energy, which is then transferred to other molecules in the atmosphere through collisions, increasing the overall temperature of the atmosphere.2. Emission of infrared radiation: After absorbing infrared radiation, CO2 molecules can also emit infrared radiation in all directions. Some of this emitted radiation is directed back towards the Earth's surface, causing further warming. This process is known as the greenhouse effect. As the concentration of CO2 in the atmosphere increases, the amount of infrared radiation emitted back to the Earth's surface also increases, enhancing the greenhouse effect and contributing to global warming.3. Positive feedback loops: The enhanced greenhouse effect due to increasing CO2 concentrations can lead to positive feedback loops that further contribute to global warming. For example, as the Earth's temperature increases, more water evaporates from the surface, increasing the concentration of water vapor in the atmosphere. Water vapor is also a potent greenhouse gas, which can absorb and emit infrared radiation, further amplifying the greenhouse effect and global warming.4. Impact on other greenhouse gases: Increasing CO2 concentrations can also indirectly affect the concentrations of other greenhouse gases, such as methane and nitrous oxide, by influencing various biogeochemical processes. For example, higher temperatures due to global warming can lead to the thawing of permafrost, which releases trapped methane into the atmosphere. This can further enhance the greenhouse effect and contribute to global warming.In summary, the increasing atmospheric concentration of carbon dioxide affects the absorption and emission of infrared radiation by enhancing the greenhouse effect, leading to global warming. This warming can trigger positive feedback loops and impact other greenhouse gases, further exacerbating the problem.