paraphrasing in 9hours

With climate change, Earth is getting warmer as greenhouse gases build up and trap more heat in the atmosphere. These warmer temperatures cause increased evaporation of water from places like oceans, lakes, streams and soil. This leads to higher levels of water vapor in the atmosphere, which means that precipitation events tend to be heavier. Whether the water falls as rain or snow depends on temperature. Therefore, if winter temperatures remain below freezing in areas like the northeastern United States, the increased moisture in the air could mean heavier snow storms.

Increased water vapor in the air can also further increase warming. Water vapor is actually a greenhouse gas, which traps heat in the atmosphere and causes temperatures to rise. But unlike other greenhouse gases that can linger in the atmosphere for years, water vapor usually stays in the air for a few days before falling back to Earth as precipitation.

So, as warm temperatures lead to more water vapor in the air, more water vapor in the air leads to warmer temperatures, which creates a positive feedback loop. A positive feedback loop is called "positive" not because it's a good thing, but rather because the effects of one process enhance the effects of another, which in turn positively reinforce the effects of the original.