Humans for years have been influencing Nebraska's weather.
Locally, research indicates that vast miles of irrigated cornfields have made the state more humid.
Urbanization creates heat islands, which is one reason Omaha's first autumn frost date tends to linger behind surrounding rural areas.
But on the larger scale is global climate change and the influence that humans have on it.
Early on, researchers were limited in the level of precision they could bring to projecting the local impact of climate change. They talked generally of “sea levels will rise” or of heat waves becoming “more frequent and pronounced.”
That is changing, and scientists are becoming more confident in projecting the regional impact of climate change.
So Wednesday, as the Nebraska Climate Assessment and Response Committee wrestled with a study of the impact on climate change in Nebraska, most of the scientists in the room already have some answers.
At the conclusion of the meeting, Michael Hayes, director of the National Drought Mitigation Center, held up a University of Nebraska-Lincoln Extension publication entitled: “Climate Change: What Does it Mean for Nebraska?”
The peer-reviewed document concludes that the state's average temperature could rise by 4 degrees by 2050 and by 8 degrees by 2090. That may not sound like a lot, but it's extraordinary. That's the average temperature; record highs will be much higher.
The UNL guide to climate change in Nebraska said this about likely warming temperatures:
“The number of days per year with daytime high temperatures greater than 95°F are expected to increase by about 15 days by the middle of this century, along with more consecutive days with highs above this threshold. Conversely, the number of days with nighttime low temperatures less than 10°F is expected to decrease by about 10 days by 2050.”
The UNL report also distinguishes between the scientific certainty over temperatures as compared to precipitation.
There is greater certainty that Nebraska will become warmer. There's less certainty about precipitation, because Nebraska sits on the dividing line between two areas of diverging climate change.
Climate change is causing areas to the north and east of here to become wetter, while areas to the south and west are becoming drier.
The study indicates that there may be seasonal variability to how precipitation plays out.
Summers generally may become drier and winters wetter.
Another study that sheds insight on what Nebraska can expect is the National Climate Assessment, a periodic federal review of climate science. The review examines climate change on a regional scale.
It notes that some areas of the United States are seeing more spring rains. As they increase, farmers could have greater difficulty getting planting done.
It also noted that nighttime temperatures are becoming warmer, which have a negative effect on corn yields by discouraging pollination.