No, E&E News, @ClimateCentral – Climate change is NOT causing Reno’s rapid warming – Is it emerging for it?

Originally published in Climate realism

In a recent article published by E&E News Climate Wire, reporter Scott Waldman declared Reno, Nevada the fastest-warming city in the United States. In this single article, titled “The nation’s fastest-warming city could decide Senate control,” Waldman made the mistake of combining climate change with Urban heat island effect (UHI), and politics.

Walman wrote:

“More than most other cities, Reno’s fate is tied to climate politics in Washington. It is the fastest-warming city in the United States and is 10.9 degrees Fahrenheit warmer than it was in 1970, according to a report. July report from Climate Central. (Las Vegas comes in second, with 5.6 degrees of warming.)”

There’s some truth in that claim about warmer temperatures since 1970, but the claim about it “combining with climate” is completely false. Multiple lines of evidence and data analysis prove it.

First, let’s consider the statement by Climate Central, the global warming advocacy group that Waldman used for his source. Central climate complain:

• Summer warming is greatest in the western and southwestern United States The three largest increases in average summer temperatures since 1970 have been in Reno, Nev. (10.9°F), Las Vegas, Nev. (5.8°F) and Boise, Idaho (5.6°F).

The temperature in those cities has increased significantly. However, Climate Central failed completely when it tried to attribute increasing summer temperatures to the increase in greenhouse gases, saying:

The heater is on. As planet-warming gases from burning fossil fuels increase the average global temperature, we are experiencing more extreme heat events. Extreme temperatures are most apparent in the summer because that’s the hottest time of year.

Waldman and Climate Central blame greenhouse gases from fossil fuels for raising temperatures, without any research or doing analysis regarding the factors that actually cause significant warming in those cities. UHI is mostly to blame.

From 2008 onward, I discovered that UHI had compromised Reno’s terrestrial temperature measurements, through a hands-on experiment to determine the intensity of UHI on summer nights. Using a calibrated digital thermometer, I drove back and forth from Reno at night while measuring the air temperature. One clear result emerged from that experiment. My experiment worked so well that now there is a citizen science-based program to conduct driving temperature measurement routes in major cities in the United States.

From the measured data, it is clear that a huge UHI signature exists near the city center and the airport. The temperature data used to claim Reno as “the fastest-warming city in the United States” comes from an automatic weather sensor, called ASOSat the airport of the city.

Even the local National Weather Service (NWS) office in Reno acknowledged the problem. They tried to move the airport temperature sensor to a cooler location away from the city that created the UHI heat bubble, further south, but was rejected by the Federal Aviation Administration (FAA) for giving that the temperature is not representative of the conditions on the runway. In a training manual they produced, they said:

Reno’s busy urban airport has seen the growth of an urban heat bubble at its northern end. The corresponding graph of the annual mean minimum temperature (average 365 degrees at night per year) has therefore steadily increased. When the new ASOS sensor was installed, the site was moved to the much cooler southern end of the runway.

…

When air traffic controllers requested a location not too close to nearby trees (for better wind readings), the station was moved back.

As seen in Figure 2 above (figure 24b from the NWS Manual) during the short time ASOS is moved, cooler temperatures prevail. It is clear that UHI-biased temperatures are reported from Reno and up. there’s even a Articles are reviewed wrote about the issue where the ASOS sensor moves at Reno’s airport been shown to cause a significant change in temperature.

Location near heat sources and sinks, such as runways and runways, is one of the most important issues for temperature data at airports used to measure climate change. The sensors are placed to provide runway conditions for aviation safety – they were never designed for climate use. The data is not suitable for that purpose. Report in 2022 Broken climate station: Official US surface temperature record still severely skewedfound that this problem occurs not only at airports but also in most weather stations that are being used to measure temperatures.

Further evidence that UHI, not climate change, is causing temperatures to rise sharply in Reno comes from an analysis conducted by climatologist Roy Spencer, Ph.D. of the University of Alabama at Huntsville, and myself.

Spencer pulled all available hourly temperature data from NOAA’s Integrated Surface Database (ISD) and perform an hour-by-hour extended analysis as shown in Figure 3 below. What he found disproves any significant climate change link with Reno’s temperature.

To interpret the graph.

• The time on the chart is in UTC (also known as Greenwich Mean Time or GMT) because that’s how the data is stored. For Reno, 6AM (summer dawn) corresponds to 14 (UTC).
• The chart clearly shows that there are strong summer warming trends during the months of May, June, July, August and September that will disappear overnight.
• In contrast, there is no trend of overnight warming during the winter months such as November, December, January and February.
• Climate change, is scientifically consistent when measured over 30 years, not selectively time on an hourly or monthly basis. What we are seeing in Reno is a localized UHI effect on summer nights.

If climate change drives Reno’s temperatures, then rapidly rising temperatures will also be evident in the winter, but Spencer’s analysis clearly demonstrates that it’s not. It is also absent during the day.

Additional support for this finding was found in a study conducted by the University of Nevada at Las Vegas,”Urban heat island effect in Nevada.” The March 2020 study looked at the UHI effect in Reno and Las Vegas, the state’s two largest cities. They found that UHI is a big problem in Nevada (emphasis mine):

Cities are warmer than surrounding countryside because they replace open areas and vegetation with sidewalks, buildings, and other heat-absorbing infrastructure. This phenomenon is known as the “urban heat island” effect. The average annual air temperature in a city with more than 1 million inhabitants can be 1.8 – 5.4°F warmer than surrounding areas during the day and warmer than 20°F at night. The heat island effect gets worse over time; Today, cities experience ten more “extreme heat events” on average today than they did in the 1950s.

UHI is also being driven by waste heat from air conditioning as detailed in a 2014 study by researchers at Arizona State University, titled “Excess heat from the air conditioner causes higher nighttime temperatures.” They wrote, “…during the night, the heat emitted by the air conditioning system increased the air temperature by more than 1 degree Celsius (nearly 2 degrees Fahrenheit) on average for some urban locations,”

Finally, another peer-reviewed study published by the University of Nevada at Reno titled Determination of Heat Island response to land cover changes from 2004 to 2017 in Reno City, Nevada there are temperature maps obtained from satellites combined with Landsat images. I annotated it to show the location of the ASOS sensor at the airport in Figure 4. It clearly shows the sensor is in the middle of the runway and by color this is the warmest part of Reno.

Waldman and Climate Central failed to study the obvious local causes behind the dramatic increase in temperature in Reno, instead simply taking the lazy route of assuming that temperatures rise. of Reno is not exactly man-made climate change. To be clear, they offer no evidence for this claim. How can they? There’s no one.

Waldman and Climate Central have chosen to advocate for honest journalism and follow science. They should be ashamed of their lack of professionalism.