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Showing posts from 2015

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

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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 "onl…

Global warming, The Wall Street Journal, and John Gordon

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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.

Hottest first six months on record

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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.

James Taylor gets polar ice wrong—as usual

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James Taylor of the Heartland Institute had a piece on Forbes back in May that escaped my attention when it first came out.  Titled "Updated NASA Data: Global Warming Not Causing Any Polar Ice Retreat", it focused on the single premise that since 2012, total polar sea ice was above the average since 1979.  Taylor then jumped to the erroneous conclusions that a) polar sea ice was not retreating and b) global warming will be entirely beneficial to humans.  His arguments are familiar, as I dealt with them before when a Newsmax article featured them back in 2014.  He's recycling old talking points, so this post is going to echo the one I wrote a year ago.

The Ice Age Cometh?

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Recent media reports have claimed that a drop in solar activity will lead to a mini-Ice Age within the next 15 years.  Unfortunately, even press reports from science-related media such as Science Daily, have been riddled with errors.

Let's get the biggest one out of the way first.  Zharkova et al. (2015) did not predict a new Little Ice Age (LIA).  What they did was use principle component analysis to detect and model magnetic waves within the sun.  They found that there were two such waves, each with an 11-year cycle, that either interfered with each other when sunspot activity was low or magnified each other when sunspot activity was high.  They then ran their statistical model ahead to make a prediction for the next solar cycle and found that their model predicts that the waves should cancel each other out, resulting in their subsequent prediction that solar activity should drop to levels not seen since the Maunder Minimum.  That bit about the Maunder Minimum is what set off th…

US versus global temperatures

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One of the talking points I see (and hear) time and again here is the question "If the world's getting hotter, why is it cold here?", "here" usually referring to the eastern United States.  Another variation goes "Global warming can't be happening because US temperatures haven't risen in _____ years."  Yes, it's the good old "It's cold in my backyard so the planet can't be warming up" argument. Here's why it's dead wrong.

The "hiatus" doesn't exist.

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That is the conclusion of a new study published in Science yesterday.  Tom Karl and his co-authors used a newly available database of weather station data that combined the Global Historical Climatology Network (GHCN) used by NOAA and NASA with over 40 other historical data sources, effectively doubling the size of the available land temperature data set.  They applied the same corrections for changes in location, urban heat island effect, etc as with the GHCN-only data set and used the same algorithms to calculate the global average over land.  To get a global average, they used the Extended Reconstructed Sea Surface Temperature dataset version 4 (ERSST4), which better integrates ship-based temperature data and buoy-based temperature data, and merged it with their new land data.  Karl et al. then created a third global temperature average that also fills in the gaps between weather stations in the polar regions.

Their new data set shows much higher trends than the GHCN-only data, esp…

Doom and gloom or realism?

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Humanity is in trouble with climate change.  A recent article in Vox by David Roberts came to that conclusion.  It begins with
"There has always been an odd tenor to discussions among climate scientists, policy wonks, and politicians, a passive-aggressive quality, and I think it can be traced to the fact that everyone involved has to dance around the obvious truth, at risk of losing their status and influence. The obvious truth about global warming is this: barring miracles, humanity is in for some awful shit."  The basis for that conclusion?  Total carbon emissions to date, which are closely following the RCP 8.5 curve from the IPCC.


That black curve is emissions to date.  We as a civilization are on track to take carbon dioxide levels to around 1000 ppm by 2100 AD.  The 12-month moving average of atmospheric CO2 levels shows that we're already at 398.83 and still accelerating upward.


That locks us into at least 1.53ºC of total warming as of now, assuming that the …

First look: UAH 6.0 vs UAH 5.6 vs RSS

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Spencer and Christy recently released a new version (version 6.0) of the UAH satellite temperature data. To see how their data has changed, I've compared the 6.0 version to the earlier 5.6 version and compared both to RSS, similar to what I did before. All calculations were made using annual data.


The difference between UAH 5.6 and UAH 6.0 is quite dramatic, especially since 2000, and the difference has grown over time.

  Comparing both UAH versions to RSS shows that while version 5.6 was consistently warmer than RSS since 2003, version 6.0 has a tendency to run cooler than RSS since 1998.


The effect all the changes from 5.6 to 6.0 had on the calculated trend was drastic. Since 1990, the average version 6.0 trend is 0.0094ºC/year lower than the same trend in version 5.6.  For version 5.6, only the trends since 1997, 1998, and 2000 were not statistically significant.  For version 6, every trend since 1993 has not been significant.






Taking a closer look, land temperatures were nearl…

The view from Greenland's highest peak

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It's amusing to me whenever a science denier cites the ice cores in Greenland as "proof" that global warming either a) isn't happening or b) isn't a big deal. It's a horrible argument for deniers to make. Here's why.

First, we're talking about ice cores taken from one location in Greenland. Not only is it one single location, but it just happens to be Greenland's highest point (10,660 feet/3,249 meters above sea level) and near the center of the continental glacier that covers Greenland. Guess what? It's going to be cold up there, just from the elevation alone, to say nothing of how all that ice affects the local temperature. Location matters. It's amusing that the same deniers who claim urban heat island when trying to explain away any warming trends seem to forget that when faced with factors that would decrease the rate of local temperature change.



Second, when we talk about global warming, we mean the entire planet, which is far large…

Using NOAA's Climate-at-a-glance widget to fact-check James Taylor

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Okay, I'm back.  Sorry for the lengthy gap between posts but work and losing my laptop intervened.  Now to get back in the saddle.

A reader by the pen name of cosmicomic asked several questions on my last post concerning James Taylor's claims about winter-time cooling in the US.  Since NOAA's climate-at-a-glance widget didn't work properly for him, I thought I'd post a video of what one should see as well as expound on the bogus method Taylor used.  Specifically, I'll examine Taylor claim that winters in the US have cooled, with the cooling trend dating back to 1930.

First, a very brief tutorial by yours truly on using NOAA's widget and what you should see when you do:


Now, Taylor's claim that US winters have cooled since 1930 is already in trouble. The simple linear regression model done by the widget shows that US winters have warmed by an average of +0.18ºF/decade since 1930. ARMA time series regression shows that the warming trend since 1930 is stat…

James Taylor has no idea what he's talking about

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A couple days ago, James Taylor of the Heartland Institute published what is one of the most disingenuous, misleading, and ignorant articles I have ever had the misfortune of reading.  It's a wonder Forbes even saw fit to publish such obvious claptrap.

Nonsense from pjscirkus about natural cycles and asteroids

A reader with the pen name pjscirkus commented on my post debunking Tom Luongo's nonsense.  Rather than add anything useful, he/she proceeded to spew enough nonsense of his/her own that I thought it best to answer here rather than in the comment thread.

What Christopher Booker wants you to ignore.

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Christopher Booker wrote a highly deceptive piece in The Telegraph on temperature adjustments in Paraguay and elsewhere around the world.  His implication is that scientists have fraudulently adjusted temperature records to show warming when there really is none.

2014, NASA, and David Rose

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An old friend sent David Rose's article in the Daily Mail claiming that NASA is only 38% sure that 2014 was the hottest year on record due to the margin of error.  Unfortunately, while Rose has his facts largely correct, he jumps to the entirely wrong conclusion.

Crossing the boundaries

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In 2009, a paper was published that measured where humanity stood in respects to the safe operating boundaries for nine environmental parameters (Rockström et al. 2009).  The nine they chose were climate change, ocean acidification, stratospheric ozone depletion, rate of biodiversity loss, biogeochemical cycles (specifically, the nitrogen and phosphorus cycles), global freshwater use, change in land use, atmospheric aerosol loading, and chemical pollution.  Using the Holocene as a baseline, they calculated threshold levels for each parameter that, when crossed, created a high risk for changes that would be damaging for human civilization.

2014 among the hottest years on record.

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This is an update to my previous post on this topic, which was based largely on January-November data.  The full-year data is rolling out and no matter who is measuring, 2014 was a hot year for the Earth.

No, a cold snap in the US does NOT mean that global warming has stopped.

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This feels like I'm in the movie Groundhog Day.  If there's a cold snap in the US, there's some science denier citing it as "proof" that there's no global warming.  This argument fails for multiple reasons.

John L. Casey and climate denial

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An anonymous commentator on my post about Tom Luongo raised the issue of John Casey and his views on climate change.  This is a valid challenge, since Luongo apparently got much of his misinformation from Casey.

Where is climate change headed?

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With the completion of yet another circle around the sun, it's time to take stock of where we're headed with global climate.  I'm going to do something that is somewhat risky—extend statistical models beyond the data range that was used to create them, but necessary if we want to see where current trends will take us in the future.