Data From More Than 9,000 Climate Stations Included in 2021 Handbook Chapter

From ASHRAE Journal Newsletter, Jan. 12, 2021

The 2021 update to the “Climatic Design Information” chapter of the ASHRAE Handbook—Fundamentals includes climate data from more than 1,100 more climate stations than the 2017 chapter.

Updated every four years, the chapter is updated with recent, reliable climate data to help building professionals size and design building components. The Handbook chapter also contributes to ANSI/ASHRAE Standard 169, Climatic Data for Building Design Standards.

The 2021 Handbook chapter includes data from 9,237 stations throughout the world, including a new location in Lagos, Nigeria, as well as an updated Weather Data Viewer that ASHRAE members will also be able to access via a new web interface currently planned to roll out in 2021.

This research provides the climatic data for ANSI/ASHRAE Standard 169, Climatic Data for Building Design Standards—especially the specification of climate zone. This informs other standards for determining requirements, such as for insulation, said Michael Roth, Ph.D., P.Eng., Member ASHRAE.

“In past years, Standard 169 typically lagged the data in the Handbook. In this cycle, we are bringing the two into sync such that both the Handbook and Standard 169 will hopefully be published in 2021,” he said.

Roth, vice chair of TC 4.2, Climatic Information, discusses the chapter’s updated information.

1. Why is the updated climatic data important?

There are many reasons, but beyond algorithmic improvements and more reported design conditions, we have more stations. The 2017 chapter saw the publication of 8,118 stations. This update will see that number rise to 9,237 stations. This means we now have design conditions in new locations such as Lagos, Nigeria, which is home to 21 million people.

2. Were there any changes in the data this time?

This update sees the development of a web interface into the climatic data for the ASHRAE membership, which allows ASHRAE members to select a weather station via a map and download the design conditions and visualization/analysis tools—all through a few clicks. We will be reporting more information on this development in 2021.

3. Were there any changes in the methodology?

This edition sees the introduction of historical trends. Our climatic data is processed and published based on the average conditions over the past 25 years. However, in many locations, we have recorded rapid changes. Where these changes are deemed statistically significant, we now report the decadal trends for some of the key design elements.

As in previous editions, we look forward to hearing how designers are using this information and anticipate evolving the reporting in the next edition based on this feedback.

4. What are your recommended best practices for how design engineers can better use this data?

In TC 4.2, we typically turn this question back on the designers. We are very receptive to hearing how design engineers use the data, how it feeds into their workflows, and more importantly what is missing. So, we ask "How can we do better?"

5. What lessons, facts and/or guidance can an engineer working in the field take away from ASHRAE RP-1847, Updating Climatic Design Information for the 2021 ASHRAE Handbook, Standard 169, and the Handbook of Smoke Control Engineering?

Globally there continues to be a persistent trend toward warming. This warming causes a knock-on effect: heating and cooling degree days decrease and rise, respectively, leading to changes in the classification of climate zones, resulting in code changes, and ending in building and equipment design adaption. I encourage every engineer to read the forthcoming Handbook chapter on climate change.

6. Were there any surprises or unforeseen challenges for you when preparing this research?

After more than 20 years of wrangling climate data, I continue to be surprised at the various clever ways that climatic data can go bad. Whether it is unit conversions, equipment failing when too hot or too cold, missing data or stations that aren't where the stations think they are, the list is endless. It is a recommendation of this research that we revisit and improve our procedures for dealing with erroneous data for the 2025 update.