Recently, a right-wing cousin of mine shared a meme claiming that
global temperatures were unchanged between 1996 and 2016, specifically
that global temperatures were 14.83ºC (58.7ºF) in both 1996 and 2016.

I call BS and here's why.

First
and most obviously, 2016 isn't even half over. Stating that the mean
temperature in 2016 was 14.83ºC (58.7ºF) is a bit premature.

Second,
whoever came up with that meme has extreme difficulty with basic
statistical terms. Here's a hint: "Average mean temperature" is
nonsense. As used in everyday speech, it's essentially the same as
saying "average average temperature" or "mean mean temperature." Now,
for those who understand statistics, I know that the mean is technically
a specific method for calculating the average but in general usage,
mean and average are interchangeable—and whoever came up with that meme
was abjectly ignorant of that fact.

Third, the meme
author had even more difficulty with facts and mathematics. For one,
the mean global temperature in 1996 was not 14.83ºC (58.7ºF). According
to NASA GISS, the average global temperature was 14.34ºC (57.8ºF). For
another, the year-to-date mean global temperature for 2016 is not
14.83ºC—it's 15.25ºC (59.45ºF). So the anonymous author has both their
start point and their end point wrong. Really wrong.

It's not just NASA that shows that 1996 is cooler than 2016. The satellite temperature records show the same.

So,
if both surface and satellite temperature records agree that 2016 is
far warmer than 1996, where is that meme author getting the lie that
1996 and 2016 have the same mean temperature?

Fourth,
that meme displays a gross ignorance in what makes up a trend by
implying that if the start and end points are the same, there cannot be a
trend. In reality, it wouldn't matter even if 1996 and 2016 did, in
fact, have the same mean temperature. A trend is far more than just its
start and end points. Even if you altered the end point, there would
still be a warming trend. It may not be as large but the trend would
still exist. Here's an example using the NASA GISS data I displayed
above. I just altered the end point of the second graph so that it
would have the same value as 1996 before I calculated the trend.

As
you can see, the warming trend still exists in the lower graph despite
altering the end point. It's not as large ("only" 0.102ºC/decade versus
0.221ºC for the original data) but it is still statistically
significant (p = 0.0257).

So in summary, whoever
made up that meme 1) lied about their numbers, 2) is ignorant of the
actual temperature data, and 3) abjectly ignorant of basic statistical
concepts. And then they had the balls to call Al Gore and progressives
liars. How quaint.

# Seeing the environmental forest

Focusing on ecology and environmental science, with sidetracks into other topics.

## Monday, May 30, 2016

## Monday, May 16, 2016

### Hottest start to a calendar year on record

NASA updated their global temperature data for April and it's hot. Really hot. As in the last time it was this hot may well be the Holocene Climatic Optimum. April 2014 shattered April 2010's record by a full 0.24ºC, coming in at 1.11ºC above the 1951-1980 baseline. That is, simply put, jaw-dropping.

## Saturday, May 14, 2016

### Climategate—Seriously??

It's hard to believe that anyone at this point takes the so-called Climategate seriously. Yet I have encountered several individuals recently who appear to sincerely believe that Climategate was a real scandal that somehow disproves all the scientific evidence for climate change/global warming accumulated over the past 150+ years.

## Thursday, May 12, 2016

### A taste of 2049

Long time, no see. Sorry for the lengthy time between entries. Real life has gotten quite complicated of late. So, let's hit one major topic that has been in the news of late: The absolutely sizzling start to 2016. Just how sizzling has it been? Take a look:

## Sunday, August 30, 2015

### What are the odds that 2015 will not be the hottest year on record?

Let me be upfront with you: I think it's a foregone conclusion that 2015 will beat out 2014 as the hottest year on record. However, I decided to test that idea, just to be certain.

The way I did it was simple: I first calculated the year-to-date average (January - July) and then calculated what the August — December average would have to be to keep the 2015 average temperature at or below that of 2014. I then calculated the August — December average for each year since 1970, fitted a trend, and calculated the standard deviation of the residuals. Last, I calculated the expected August - December average for 2015 given the trend and the difference between the expected August - December average and what that average would have to be to keep 2015 from setting a new record. I then used z-scores to calculate the probability that the remainder of 2015 would fall to that level or below.

Year to date, 2015 sits at +0.82ºC above the 1951-1980 baseline. The average for 2014 was "only" +0.75ºC above the baseline. Keeping 2015 at or below the standard set by 2014 would require an average temperature of at most 0.652ºC for the remainder of the year. So, how likely is that average temperature for the August - December period?

The predicted average for August - December 2015 based on the trend would be 0.772ºC, more than enough to make 2015 the hottest year on record. With a standard deviation of 0.0981ºC, there is only an 11.05% chance that the August - December 2015 average would be at 0.652ºC or below. This means that right now, 2015 has at least an 88.95% chance of breaking 2014's record. Pretty good odds but not quite a foregone conclusion.

There is one important caveat that means that I overstate the chance that 2015 will not break the record: I did not account for El Niño years. That was done deliberately. I wanted to be conservative with my estimate. With a strong and strengthening El Niño event in the Pacific that might rival the 1983 and 1998 El Niños, I personally believe that 2015 has a nearly 100% chance of smashing 2014's record baring a major volcanic eruption.

The way I did it was simple: I first calculated the year-to-date average (January - July) and then calculated what the August — December average would have to be to keep the 2015 average temperature at or below that of 2014. I then calculated the August — December average for each year since 1970, fitted a trend, and calculated the standard deviation of the residuals. Last, I calculated the expected August - December average for 2015 given the trend and the difference between the expected August - December average and what that average would have to be to keep 2015 from setting a new record. I then used z-scores to calculate the probability that the remainder of 2015 would fall to that level or below.

Annual global temperature according to NASA GISS since 1970 |

Year to date, 2015 sits at +0.82ºC above the 1951-1980 baseline. The average for 2014 was "only" +0.75ºC above the baseline. Keeping 2015 at or below the standard set by 2014 would require an average temperature of at most 0.652ºC for the remainder of the year. So, how likely is that average temperature for the August - December period?

Average August - December temperatures since 1970. |

There is one important caveat that means that I overstate the chance that 2015 will not break the record: I did not account for El Niño years. That was done deliberately. I wanted to be conservative with my estimate. With a strong and strengthening El Niño event in the Pacific that might rival the 1983 and 1998 El Niños, I personally believe that 2015 has a nearly 100% chance of smashing 2014's record baring a major volcanic eruption.

## Saturday, August 8, 2015

### Global warming, The Wall Street Journal, and John Gordon

John Steele Gordon published a commentary
in The Wall Street Journal on July 30 that, on its face, sounds
reasonable. Gordon makes the case that we should be cautious about
calling climate science settled as science is always changing. No real
quibbles there, as science has shown that nothing is ever truly
"settled" science. Unfortunately, that's as close to reality as Gordon
comes. The rest of the commentary simply shows off Gordon's simplistic
view of history, science, and, especially, the current state of climate
science.

## Saturday, August 1, 2015

### Hottest first six months on record

I know, I know, I'm behind a bit. Most of the stories on the first six months of this year came nearly a month ago. Better late than never. By now, we all know that the world is headed toward its hottest year ever, breaking the record set just last year. In this post, I'm going to analyze just how abnormal normal the first half of the year has been.

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