Trend for average temperature in Grand Rapids, Michigan shows an anomaly of less than +0.5 degrees F after 124 years

 Could be just a heat island effect from KGRR.

Average temperature in 2021 in Grand Rapids, Michigan, was the eighth highest on record in 124 years

The trend line after 123 years of data shows average temperature in Grand Rapids, Michigan, rising 0.7 degrees F, or 0.388 degrees C, 65% less than the 1.1 degrees C claimed for the world by the United Nations Intergovernmental Panel on Climate Change yesterday.

And the minimal warming in Grand Rapids may in fact be misleading. Five of the data points in those top eight are from the last twenty-five years, during which increasing development around the KGRR measuring station may well be contributing heat island effects.

 

 

Given urban heat island distortions of +1 to +7 degrees F, average temperature rise of less than 0.3 degrees F above the mean since 1898 in Grand Rapids, MI is suspect

Given urban heat island distortions of +1 to +7 degrees F, average temperature rise of less than 0.3 degrees F above the mean since 1898 in Grand Rapids, MI is suspect (image D).

US EPA Heat Islands page:

"A review of research studies and data found that in the United States, the heat island effect results in daytime temperatures in urban areas about 1–7°F higher than temperatures in outlying areas and nighttime temperatures about 2–5°F higher. Humid regions (primarily in the eastern United States) and cities with larger and denser populations experience the greatest temperature differences. Research predicts that the heat island effect will strengthen in the future as the structure, spatial extent, and population density of urban areas change and grow".

The US Historical Climatology Network station in Grand Rapids, Michigan, looks increasingly compromised by urban heat island effects. It is located at the Gerald R. Ford International Airport (image A), where the main 8,500 foot runway did not become operational until 2001 and where 2 million passengers were not served for the first time until 2004.  

The weather station is located in the northwest corner of the 3,000 plus acre airport grounds at 4899 Tim Dougherty Dr, Grand Rapids, MI 49512 (image B). One can see it is now surrounded by industrial development to the north and west, the airport to the south and east, and a busy county road commission facility right east of the measurement station, which is accessed by a little walkway leading from the National Weather Service building (image C).

The county population has doubled in the last sixty years.

One can observe from the history of maximum temperature at the station (image E) that the trend is clearly lower by nearly 1.5 degrees F from the mean maximum over the whole period. The trend for minimum temperature is even lower, by over 2.0 degrees F from the mean (image F).

Click any image to enlarge.

A

B

C

  

D

E

F

Trend for average temperature in Grand Rapids, Michigan, indicates warming of about +0.5 degrees F over the last 120 years

That's it.

The not-much-of-a-muchness of it suggests that the growth of heat island effects could easily account for the observed results.

IPCC puts global warming at +1.53 degrees F 1880-2012, over 3.8 times what it was in Grand Rapids, Michigan

The average temperature trend in Grand Rapids, Michigan shows warming of about only 0.4 degrees F over the 120-year record from 1898 through 2017, according to NOAA online weather data for the station. The relatively small increase combined with the recency of the highs for the data series, however, makes one wonder about possible interference from developing heat island effects at the station, which is located near the increasingly busy Ford International Airport.

The Intergovernmental Panel on Climate Change figure of 1.53 degrees F is referenced here.

The data for Grand Rapids is shown below.