What is the effect of increased methane levels in the environment?

Increased methane levels in the environment trap more heat, leading to a rise in temperature. Methane is a potent greenhouse gas, with a much higher global warming potential compared to carbon dioxide over a short time frame. When methane molecules are present in the atmosphere, they absorb infrared radiation emitted from the Earth's surface, preventing it from escaping into space. This enhanced greenhouse effect contributes to an overall warming of the planet.

The other options do not accurately reflect the role of methane in the atmosphere. For instance, while the reduction in atmospheric temperature would typically be associated with processes that remove heat, increased methane intensifies warming. Similarly, methane does not contribute to decreasing humidity, as humidity is largely influenced by moisture content in the air, rather than the presence of methane. Lastly, while methane can participate in reactions that may form clouds eventually, its most immediate effect is the increase in atmospheric heat retention.