The Book That NOAA Should Have Published: Extremes and Averages in Contiguous U.S. Climate

New climate data reference book presents data that NOAA doesn’t.

Graphs of 100 Years of NOAA Contiguous U.S. Climate Data (2018 Edition) – A Book That NOAA Should Have Published

Guest Post by Bob Tisdale

I’ve just published a new book titled Extremes and Averages in Contiguous U.S. Climate. It is only available through Amazon HERE in paperback form (400+ pages, 8½ x 11).  The price is $57.21.  I have no plans to publish an ebook edition.

Extremes and Averages in Contiguous U.S. Climate is intended for all U.S. residents who are serious about their data-based understandings of climate change in the Contiguous United States as a whole and regionally, and for its individual 48 states. Further, even if you don’t agree with the NOAA data, you should at least understand the stories their data tell.

The source of the data used to create the graphs in Extremes and Averages in Contiguous U.S. Climate is the NOAA National Data Center Climate Data Online (NNDC CDO) website.

OVERVIEW FROM EXTREMES AND AVERAGES IN CONTIGUOUS U.S. CLIMATE (Brackets include notes for this blog post.)

This book presents time-series graphs of NOAA climate data for the United States. More specifically, for the 100-year period of 1919 to 2018, this book presents time-series comparison graphs of the highest of the monthly highs per year and the lowest of the monthly lows per year—the extremes—and also the averages per year for NOAA:

• Precipitation (PCP) data (presented in inches),
• Palmer Drought Severity Index (PDSI) data, and
• Near-surface air temperature (TMAX, TAVG, & TMIN) data (presented in degrees Fahrenheit)…

…for the Contiguous United States as a whole, for the 9 NOAA Climate Regions of the Contiguous United States shown in Figure Overview-1, and for the 48 (contiguous) States individually. The data are presented in their observed forms (or calculated form in the case of the drought data), not as anomalies. The extremes and averages were extracted by MS EXCEL from NOAA monthly data from January 1919 to December 2018.

Additionally, there are comparison graphs of the annual cycles in near-surface air temperatures, based on 30-year averages of the monthly values—the first 30 years of that 100-year period (1919-1948) versus its last 30 years (1989-2018)—for each of the temperature metrics (TAVG, TMIN, and TMAX). These are provided to show readers how the annual cycles in surface temperatures (based on average monthly temperatures) have changed between those two time periods.  These comparison graphs of the annual temperature cycles are provided for each state, each region and for the Contiguous U.S. as a whole.

Another Feature of this book:

NOAA ADJUSTMENTS TO THE TEMPERATURE DATA

After the Introduction, the graph presentations begin with the adjustments NOAA has made to the average temperature (TAVG) data for the contiguous United States and for each of the 9 NOAA climate regions. At their website, NOAA is open about the adjustments they’ve made to the near-surface air temperature data. This book would be incomplete without illustrations of the effects of those adjustments.  To that end, I present graphs that compare the current editions and the 1984 editions of the annual mean near-surface air temperature (TAVG) data for the Contiguous United States as a whole and for the 9 NOAA U.S. Climate regions.  The 1984 editions of the average near-surface air temperature data are being presented as the data before the adjustments.  Those older data were found in the 1984 paper Regional and National Monthly, Seasonal, and Annual Temperature Weighted by Area, 1895-1983 by Karl and Koss. The paper can be found here: (https://repository.library.noaa.gov/view/noaa/10238).

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After the introductory explanations, the data presentations are made without comment from me.

The NOAA website that served as the source of the data in this book is the NOAA National Data Center Climate Data Online (NNDC CDO) website.

https://www7.ncdc.noaa.gov/CDO/CDODivisionalSelect.jsp#

The period of 1919 to 2018 was chosen for two simple reasons. First, it covers the last 100 full years of data, and, as such, no one can realistically claim that I’ve cherry picked the start and end years.  Second, the trends are shown in units per decade, so readers only have to multiply the trend listed on the graphs by ten to determine how much the metric has changed in those 100 years based on the linear trend.

The 9 NOAA Climate Regions are shown in Figure Overview-1. They include:

• Northeast Region (includes the states of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont)
• East North Central Region (includes the states of Iowa, Michigan, Minnesota, and Wisconsin)
• Central Region (includes the states of Illinois, Indiana, Kentucky, Missouri, Ohio, Tennessee, and West Virginia)
• Southeast Region (includes the states of Alabama, Florida, Georgia, North Carolina, South Carolina, and Virginia)
• West North Central Region (includes the states of Montana, Nebraska, North Dakota, South Dakota, and Wyoming)
• South Region (includes the states of Arkansas, Kansas, Louisiana, Mississippi, Oklahoma, and Texas)
• Southwest Region (includes the states of Arizona, Colorado, New Mexico, and Utah)
• Northwest (includes the states of Idaho, Oregon, and Washington)
• West Region (includes the states of California, and Nevada)

[Reference link for blog post here.]

Figure Overview-1

IMPORTANT NOTE: I am not and have never been an employee of NOAA or any other U.S. government agency. I am an independent climate researcher and data presenter.  Online, I have been presenting graphs of climate-related data for more than a decade—thousands of graphs—at my blog ClimateObservations and at the World’s Most Viewed Site on Global Warming and Climate Change, which is a blog called WattsUpWithThat.  [End note.]

The data that serves as the source for the graphs contained in this book are identified at the NOAA National Data Center Climate Data Online (NNDC CDO) website as:

• PCP – Precipitation Index
• PDSI – Palmer Drought Severity Index
• TAVG – Temperature Index
• TMIN – Minimum Temperature Index
• TMAX – Maximum Temperature Index

OTHER DATASETS AVAILABLE AT THE NOAA NNDC CDO WEBSITE BUT NOT INCLUDED IN THIS BOOK

For those interested, in addition to the datasets listed above that are presented in this book, the output pages of the NOAA Climate Data Online website include numerous other climate-related datasets, which are listed below:

• PHDI – Palmer Hydrological Drought Index
• ZNDX – Palmer Z-Index
• PMDI – Modified Palmer Drought Severity Index
• CDD – Cooling Degree Days
• HDD – Heating Degree Days, and
• SPnn – Standard Precipitation Index

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Note: If you haven’t yet purchased this book and are reading this overview online or in a bookstore, you may be asking yourself, Why should I buy this book, when I can look at climate-data graphs for free at the NOAA Climate at a Glance website and then download the graphs and related data for my own records?

The primary reason to buy this book instead of going to the NOAA Climate at a Glance website is this book presents climate extremes in ways the NOAA website does not. Specifically, the NOAA Climate at a Glance website does not extract and illustrate the extreme values per year (the highest of the monthly values per year and the lowest of the monthly values per year) for the Precipitation data and Palmer Drought Severity Index data as this book does. Additionally, while the NOAA Climate at a Glance website does provide and illustrate monthly high temperature (TMAX) data and monthly low temperature (TMIN) data, it does not extract and show the extreme values of those metrics per year (the highest of the monthly highs for the TMAX data per year and the lowest of the monthly lows of the TMIN data per year), but this book does present them and their linear trends.

[End note.]

Keep in mind that annual averages are based on 12 months of data each year, while only two months per year are selected for the annual extremes (one for the highest high and one for the lowest low), and, as everyone knows, there can be large changes in precipitation, drought conditions, and temperatures every month. Thus, the extremes are important, and they do not always follow the averages.  This is especially true for the temperature extremes, which in this book are represented by the highest monthly high temperatures per year and the lowest monthly low temperatures per year, not by the highest and lowest values per year of the average temperatures.

Additionally, changes in precipitation, drought severity and near-surface air temperatures differ from NOAA climate region to NOAA climate region and from state to state—even neighboring states—in ways that may surprise you.

The Introduction, which follows [not in this blog post], includes a complete set of graphs based on the data for the Contiguous United States. Because they are important, I’ve included the graphs for the Contiguous United States again near the end of the book as well.

By the way, it was the inability to extract and show the extreme values per year (highest of the monthly highs and lowest of the monthly lows per year) in graph form at the NOAA Climate at a Glance website that prompted me to prepare this collection of graphs of NOAA data for the contiguous U.S.  Many persons, like me, are more interested in climate extremes than they are in averages.

In my experience, the NOAA National Data Center Climate Data Online (NNDC CDO) website is much faster than the NOAA Climate at a Glance website, the latter of which can be very slow at times…so slow it discourages efforts to study climate data.  The NOAA National Data Center Climate Data Online (NNDC CDO) website worked quickly (within seconds) each time I clicked on Submit, and it presented all datasets on one text output sheet, which drastically shortened my data-download time while preparing this book.

My apologies to the residents of Alaska and Hawaii, but the NOAA website used as the source of data for this book does not supply data for Hawaii, and the data are incomplete for Alaska during the period of 1919 to 2018.

[END OF OVERVIEW PREVIEW]

SAMPLE GRAPHS

The following are examples of the 6 graphs presented in Extremes and Averages in Contiguous U.S. Climate for the Contiguous United States as a whole, for each of the 9 NOAA climate regions that make up the Contiguous U.S., and for each of the 48 Contiguous U.S. states individually.  The examples are for the State of Vermont.

Why did I use Vermont for the samples? I didn’t want to be accused of cherry-picking examples to support a point of view, and the data for Vermont didn’t present anything extraordinary either way.

The numbering of the sample graphs coincides with the numbering of the datasets at the NOAA NNDC CDO website, which is the source of the data for the graphs presented in Extremes and Averages in Contiguous U.S. Climate.   The lettering was chosen by me and remains constant throughout the presentations.

Figure-43a

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Figure-43b

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Figure-43c

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Figure-43d

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Figure-43e

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Figure-43f

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An example of a graph that presents the TAVG data and corresponding trends before and after NOAA made adjustments to them can be seen in Figure Old v Current TAVG Data-6, which is for the NOAA South climate region. The South climate region includes the States of Arkansas, Kansas, Louisiana, Mississippi, Oklahoma, and Texas. In the book, these comparison graphs are provided for each of the 9 NOAA climate regions of the Contiguous U.S. and for the Contiguous U.S. as a whole, and they cover the period of 1919 (the start year of the graphs in this book) to 1983 (the last full year of data from the 1984 NOAA paper Regional and National Monthly, Seasonal, and Annual Temperature Weighted by Area, 1895-1983 by Karl and Koss, which is the source of the older TAVG data.

Figure Old v Current TAVG Data-6

Like the samples above for Vermont, I selected the South region for this example because it didn’t show anything extraordinary, either way. That is, the South region is close to middle-of-the-road based on the impacts of the NOAA adjustments to the TAVG linear trends during this period.  On the other hand, for the period of 1919-1983, out of the 9 NOAA climate regions of the contiguous U.S., the South region has the smallest (downward) offset in TAVG temperature between the older edition data and the current (adjusted) edition, only -0.8 deg F, with the older edition data subtracted from current.

Additionally, for the period of 1919-1983, and for the contiguous U.S. and its 9 NOAA climate regions, this book also includes (1) a comparison graph of the differences between the trends of the old and current TAVG data, with the older data subtracted from the current data, and (2) a table that, for each region and the contiguous U.S. as a whole, shows (a) the trends of the TAVG data before and after the adjustments along with their differences and (b) the average TAVG temperatures and offset in TAVG temperatures for the period of before and after the adjustments, again with the older data subtracted from the current data.

If you’ve assumed NOAA’s adjustments to the TAVG data have impacted all regions similarly, you’ve assumed incorrectly.

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ONE GRAPH PER PAGE

As noted in the opening paragraph of this post, Extremes and Averages in Contiguous U.S. Climate is more than 400 pages long, and it’s printed on 8 ½ x 11 paper. Why 400+ pages? For the graph presentations of the NOAA data, each graph is presented on a separate page, with enough space in the margins for your hand-written notes.  See Photo-1.

Photo-1 (Click to Enlarge)

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A FEW NOTES FROM THE INTRODUCTION ABOUT THE GRAPHS

…not all regions and states show three quasi-parallel trend lines for the average and two extremes of their respective Palmer Drought Severity Index data like those shown in [Figure 43b for this blog post].

You’ll note on the extremes and average comparison graphs that I’ve also left the trend-line equations created by MS EXCEL. That was done for two reasons.  First, some readers may want to calculate the values of the trend lines at any year from 1919 to 2018, and the trends line equations will allow them to do so.  Second, including the trend line equations on the graphs helps to assure readers that the trends I listed in color-coded boldface are the trends calculated by MS EXCEL.  You’ll also note that the values of the trends in the EXCEL trend-line equations are presented per year, but I list them on the graphs as per decade.

# # #

If isolating the highest and lowest Palmer Drought Severity Index (PDSI) data per year from the average per year is new to you, consider this: (1) the highest annual PDSI data is useful for comparing wettest periods, and, (2) the lowest annual PDSI data is useful for comparing driest drought periods.

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IMPORTANT NOTE ABOUT TRENDS

For the Precipitation (PCP) and Palmer Drought Severity Index (PDSI) data, do not expect that the trends for annual maximums and minimums to average out to equal the trend for the annual averages. The annual averages consider 12 months per year, while the annual maximums and minimums examine only one month each per year.

Similarly, do not expect the trend for the annual average temperature (TAVG) data to equal the average of (1) the trend of the annual highest of the high temperatures (which are extracted from the TMAX data) and (2) the trend of the annual lowest of the low temperatures (which are extracted from the TMIN data). The annual average of the TAVG data considers 12 months per year, while the annual maximum of the TMAX data and annual minimum of the TMIN data examine only one month each per year.

# # #

The data furnished at that NOAA NNDC CDO website do not include uncertainties, so uncertainties are not shown on the graphs in this book.  That is consistent with the NOAA Climate at a Glance website, which also excludes uncertainties with the trends it presents. See the sample output graph from the NOAA Climate at a Glance website in Figure Intro-19 to confirm that they do not include uncertainties in their graphs there.

Figure Intro-19

CURIOSITIES

There are a number of curiosities in the NOAA data presented in Extremes and Averages in Contiguous U.S. Climate. Prime examples exist in the annual cycle comparison graphs for the Minimum Temperature (TMIN) data for three states: New Jersey, New York, and Pennsylvania. (A sample of that type of graph is shown above in Figure 43e.)  Normally, for both 30-year periods, the average February TMIN temperature is noticeably higher than the January TMIN temperature.  But, for those three states, during the early 30-year period of 1919-1948, the January and February TMIN temperatures are so close, the graph’s curve between them appears to be flat.  In other words, for the period of 1919-1948, the 30-year averages of the extreme low temperatures for those three states were very similar in January and February. In a couple of weeks, I may prepare a blog post about that extended lowest-of-the-low TMIN temperatures phenomenon.

DATA HAVE BEEN ARCHIVED

Just in case there are noticeable changes to the data at the NOAA National Data Center Climate Data Online (NNDC CDO) website in the future, I’ve uploaded to one of the online archives all of the NOAA NNDC CDO data pages I relied on when I prepared the graphs for this book.

PLEASE DO NOT COPY ANY OF THE GRAPHS FROM THIS BOOK FOR ANY REASON

Enough said on that subject.

The exceptions to that request, of course, are the graphs that were presented in this post and only those graphs.

CLOSING TO POST

In 2018, I also prepared an ebook for those of you interested in:

• the number of hurricanes that make landfall here in the continental United States,
• the number of tornados that touchdown in the Contiguous U.S.,
• flood data for the states, and
• wildfire data, too.

I made those data presentations in my Kindle ebook short story titled Dad, Is Climate Getting Worse in the United States?.  The subtitle of that short story is Book 2 in the DAD, WHY ARE YOU A GLOBAL WARMING DENIER? Series.

I suspect many of you are thinking that Extremes and Averages in Contiguous U.S. Climate would make a great gift for politicians who sound very confused about climate change here in the United States…and also for family members and friends for the same reason.  I agree.

Again, Extremes and Averages in Contiguous U.S. Climate can be purchased through Amazon HERE in paperback form (400+ pages, 8 ½ x 11).

Thank you very much to those who have purchased or will purchase Extremes and Averages in Contiguous U.S. Climate.

Regards,

Bob Tisdale