Friday, October 9, 2015

Why Hasn't Ted Cruz Been Called Out For Using UAH Data To Deny Global Warming

Ted Cruz is passionate in his denial of global warming. And if you listen to him, he has his message down pat. But an aspect of his denialism that he doesn't seem to get called out on is his use of temperature records from the University of Alabama at Huntsville. Cruz is ignoring NASA, the UK Met Office, the Japan Meteorological Agency, and numerous other highly respected sources to cherry pick as his source of temperature records the data set produced by global warming deniers at the University of Alabama at Huntsville.

According to the Open Mind blog
There are 5 major sources of global temperature data which are most often referred to. Three of them are estimates of surface temperature, from NASA GISS (Goddard Institute for Space Studies), HadCRU (Hadley Centre/Climate Research Unit in the U.K.), and NCDC (National Climate Data Center). The other two are estimates of lower-troposphere temperature, from RSS (Remote Sensing Systems) and UAH (Univ. of Alabama at Huntsville).
And there are numerous institutions that analyze the data and provide measurements of the global temperature using both satellite generated data and land/sea based temperature stations, as detailed in the Why So Many Global Temperature Records

Maybe it's just me, but I have more trust in NASA, NOAA, the UK Met Office, and the Japan Meteorological Agency than I do in a source that is denying global warming based on estimating the lower troposphere temperature from satellite microwave sounder data, as the University of Alabama Huntsville team is doing. In fact, The Journal of Climate published a study that showed why the University of Alabama at Huntsville team was underestimating global warming. Additionally, Skeptical Science posted on why this was a flawed data source.

One of the reasons the UAH data is flawed is due to orbital decay in the paths of satellites. Hmmm, who do you think is better at adjusting satellite data for orbital decay -- a small group of researchers at UAH or the team at NASA? Also, it strains credibility to assume that satellite microwave sounder measurements of the troposphere are a better source of global surface temperature estimates than land and sea based temperature gauges.

Cruz also uses the other source satellite microwave sounder temperature reports, Remote Sensing Systems, to support his global warming denialism. However, Carl Mears the senior scientist at Remote Sensing Systems (RSS) "criticizes Cruz's approach and conclusions". Mears also indicates that it is likely that there are more errors in the RSS reports than in the temperature estimates from  surface measurements.

In addition to Cruz cherry picking his data source, he also cherry picks his time frame. His "zero warming" claim is based on using an abnormally warm outlier year, 1998, as the starting point for his claim that there has been no warming in the past 17 years. There is significant variability in temperature from year to year, and it's hard to take seriously a trend analysis based on cherry picking an outlier year as the staring point. The upward trend in global surface temperatures is obvious to the naked eye if any of the other nine years in the 1990's is utilized as the starting point.

Ted Cruz's climate denailism sort of falls apart once you realize that it is based on his cherry picking a flawed source of temperature records. Legitimate analysis is not based on cherry picking data.

Additional Reading

Rate of Sea Level Rise Has Doubled Since 2014. Trend or Outlier?

Sea Ice - Another Climate Science Denier Claim Melts Away

Sunday, September 20, 2015

Sea Ice Has Declined by 900,000 Square Miles This Year

The sea ice extent at the north and south poles has undergone a massive decline this year. Antarctic and Arctic sea ice extent have declined by 1.83 million and 550,000 square kilometers, respectively, in the past 365 days. Thus, total sea ice extent has declined by 2.4 million square kilometers (over 900,000 square miles). For perspective, this reduction in area covered by sea ice at the poles is 5 and a half times the size of California.

Antarctic sea ice declined from 20.1 million square kilometers to 18.3 million kilometers on September 20 from 2014 to 2015 according to the National Snow & Ice Data Center. Arctic sea ice declined by from 5.1 million kilometers to 4.5 million square kilometers during this period. (For reference, 1 square kilometer equals 0.386 square miles)

Antarctic Sea Ice Extent
(area of ocean with at least 15% sea ice extent

Click on image to view interactive larger version of this chart (next click on Antarctic button)

Arctic sea ice is in a long term downtrend. This year featured the lowest maximum extent and fourth lowest minimum in recorded history. On the other hand, Antarctic sea ice extent had been increasing from 2011 through 2014. The trend in Antarctic sea ice extent abruptly reversed in July, 2015. In the past year Antarctic sea ice has gone from record extent to a below average extent (average based on 1981-2010).

Arctic Sea Ice Extent
(area of ocean with at least 15% sea ice extent

Click on image to view interactive larger version of this chart

It's probably questionable whether combining Antarctic and Arctic sea ice extent generates a particularly meaningful metric. The warming planet is the primary reason for shrinking Arctic ice, whereas there are complicated counter balancing factors at play in the Antarctic,  The changes in extent between the two poles are not equivalent. The numerous factors influencing Antarctic sea ice extent create interactions that are the subject of ongoing research. Some scientists have speculated the melting land based Antarctic glaciers may produce incremental sea ice, while others are focusing on wind patterns.

It is also suspect to focus on data from a single year, as opposed to multi year trends. Despite these qualifiers, the decline this year should put to bed the idiocy spouted by climate science deniers that global warming is a hoax because sea ice is increasing. The deniers' claim that the decline in Arctic sea ice was compensated for by an increase in Antarctic sea ice was always absurd, and at this point can only be made by cherry picking results from periods that exclude July through September 2015.

Additional Reading

Friday, September 4, 2015

Rate of Sea Level Rise Has Doubled Since 2014. Trend or Outlier?

During the past year and a half, the rate of sea level rise has doubled. Sea level has risen at a rate that projects out to over 0.2" per year.  The sea level rise over the last 20 months has jumped from the previous two decades rate of 0.1".  Given that there is a great deal of variability in the rate of in sea level rise on a short term basis, it's hard to judge whether the sea level rise is accelerating, or if this increase is just a short term aberration.  As shown in the chart below, while the trend in sea level is clearly upward, there is a great deal of variability on a year to year basis. During the past two decades, any big jumps or declines in sea level rise have been followed by reversion to the trend line.

If the sea level rise is carried out to an additional decimal point, the sea level has been rising at a rate of 3.2 mm ( 0.12") per year over the past couple of decades. Thus, being more precise, the rate of sea level rise since the start of 2014 has increased from 0.12" to more than 0.24" annually.  (for reference 0.1" is equivalent to 2.54 mm)

For a finer level of detail, monthly reports on sea level rise are provided by CSIRO

The rate of sea level rise has enormous implications for long term planning purposes. If the rate of sea level rise reverts to the mean and continues at 0.1" per year, then it may be decades before rising sea levels cause massive problems. If an annual sea level rise of 0.2" is the new normal, then there is likely to be a dramatic increase in tidal and storm related flooding in less than two decades. And if the rate of sea level rise continues to accelerate, as the vast majority of climate researchers predict, sea level could rise by 8" or more by mid century. 

Sea level rise offers a dramatic example of why proposed actions to reduce greenhouse gas emissions are so controversial. The majority of today's voters may well be dead before the impacts of rising sea level become catastrophic, sometime between 2050 and 2100. Given the uncertain long term benefits of various actions to reduce fossil fuel burning, and the immediate economic pain to be caused, solution aversion is an understandable reaction. Of course, for those that care about the world that they are leaving to their grandchildren and/or hope to still be around in 2050, continuing down the current path of annual global emission of 9 billion metric tons of CO2 is frightening.

With the past year and a half  being the hottest in recorded history, it's not surprising that there has been an increase in the rate of sea level rise. The high recent temperatures are in part due to El Nino. Thus, once El Nino conditions end, there may be a small decrease in global temperatures and sea level rise.  However, on a long term basis, climate researchers predict that the rate of sea level rise will accelerate. As shown in the following chart, the projected rise in sea level becomes a huge problem after 2050. If these projections are correct, the current refugee problem in Europe could become exponentially worse as coastal areas become uninhabitable.

The costs of dealing with rising seas will be enormous. Miami has already spent $15 million on pumps to keep tidal waters from rising on city streets and plans on spending an additional $500 million. Miami's spending may only be a pittance compared to the future cost of defending against coastal flooding. The authors of a study published in Nature Climate Change suggest that spending
of $50 billion per year will be required through 2050 to defend against coastal flooding.


Climate researchers have warned that sea levels rise is accelerating. It's logical to conclude that glacial and arctic ice melt will occur at a more rapid rate in a warming world. Time will tell whether the acceleration in sea level rise started picking up speed in 2014.

Tuesday, August 18, 2015

Has Growth in Antarctic Sea Ice Extent Suddenly Halted?

Antarctic sea ice extent has barely increased so far this month. In a typical year, Antarctic sea ice extent would have increased by over a million square kilometers during the first half of August. There is no telling whether the results of the last few weeks is just an aberration or the start of a trend.

However, the minimal growth of Antarctic sea ice extent makes a mockery of claims being made by climate science deniers as recently as last month. A favorite tactic of climate science deniers is to claim that the growth in Antarctic sea ice extent offsets the decline in Arctic sea ice extent. And while this type of comparison was misleading even when the Antarctic sea ice extent was expanding, it is downright absurd this month in which the Antarctic sea ice extent has returned back to it average extent during 1981-2010.

While Antarctic sea ice extent has been flat lining during a winter period when it usually expands, Arctic sea ice extent has been melting faster during the past few weeks than it did during the most recent couple of years.

It seem ludicrous that Christopher Booker of The Telegraph was claiming "How Arctic ice has made fools of all those poor warmists" back on  July 25, 2015. In his article, Booker made of point of indicating Arctic sea ice extent was higher in 2015 than in 2013 and 2014. Well, as one can see from the image below, Arctic sea ice in 2015 has been both above and below that of the previous two years over the course of this year. However, on the date Booker published his article, Arctic sea ice extent was already trending lower than the previous two years, and has stayed lower throughout August. In fact, based on the current trend, it seems likely that 2015 Arctic sea ice extent summer melt minimum will be the 5th lowest in recorded history, and well below the levels of 2013 and 2014. He also made the spurious argument that Antarctic sea ice growth counterbalanced Arctic sea ice declines. Well, that claim goes up in smoke due the sudden halt in expansion of Antarctic sea ice extent this month.

Time will tell whether the increase in Antarctic sea ice extent has come to a halt. It would not be surprising if there is some increase of the ice extent during September or early October, the period when Antarctic sea ice extent reaches it's annual winter maximum. However, it is not unreasonable to speculate that Antarctic sea ice extent may have returned back to its average range. 

Related Articles

Monday, August 17, 2015

The Revised Republican Presidential Candidate Message on Climate Change - "It's natural"

During mid-January, 2016, it will be announced by NASA, NOAA, and the Japan Meteorological Agency that 2015 was the hottest year in recorded history (Given that 5 of the first 7 months during 2015 have been the hottest for their respective history, it is not so much a question of will 2015 be the hottest year in recorded history, but one of "by how much will it be the warmest?"). At this point, it will become pretty difficult for any political candidate to continue to claim that "global warming is a hoax" without losing credibility among all except those that are in deepest denial. A few Republicans, including Donald Trump, James Inhofe and Rick Santorum, may continue to spout the "hoax" myth, but any candidate that wishes to appeal to a mainstream audience will lose credibility if they deny that we live on a warming planet.

A logical mantra for a presidential candidate that wants to appeal both to the Republican base during the 2016 primaries and also to a mainstream audience during the general election, is to indicate the warming of the planet is "natural". This claim that the warmth of 2015 is "natural" can be supported by indicating that it is part of a trend that has been going on in the short term since the end of "the little ice age" and in the long term since the end of the "ice age".

Given that most of the 2016 Republican primaries will be held during winter, the seasonally cold weather will probably dampen the attention drawn by "global warming" and thus make it easier to down play this issue.

Joining the consensus of climate scientists, and agreeing that mankind is contributing to climate change is going to be challenging for any Republican candidate. The problem is that American voters are unlikely to accept a position of indicating that there is a problem, but not recommending taking any action in regard to the problem. And the various solutions proposed to combat climate change are antithetical to conservative Republicans. New and/or stricter regulations that limit carbon emissions are a non-starter. Supporting a carbon tax would almost certainly be political suicide for a Republican candidate in the primaries. According to a Rasmussen Reports poll, 65% of voters would be opposed to actions that cost them more than $100 a year,
Forty-one percent (41%) say they’re not willing to pay anything more in taxes and utility costs to generate cleaner energy and fight global warming. Another 24% are willing to spend only $100 more per year.

Here are some of the positions Republican presidential candidates can espouse on global warming:

1. It's a hoax
2. I'm not a scientist
3. The data is inconclusive
4. Climate change is natural
5. Mankind is contributing to climate change

Of the above, the first (hoax) would be damaging in the general election. The fifth (anthropogenic climate change) would be a vote killer during the primaries. The second and third claims above come across as awfully lame. Thus, the most logical position for a Republican presidential candidate on climate change is the fourth above, that climate change/global warming is natural. It's instructive that Lindsay Graham, the only Republican candidate that suggests climate change denial will be a problem for the party in 2016, is barely registering in the polls

Additional Information

For reference here are links to a couple of sites that:1) explain why the rise in global temperatures is not simply a continuation of a trend, and 2) another site that makes the case that recent "global warming" is natural



Wednesday, August 12, 2015

Sea Ice - Another Climate Science Denier Claim Melts Away

Climate science deniers are notorious for trying to dismiss climate change by cherry picking dates and massaging data in attempts to obfuscate signs that our planet is warming. In particular, science deniers attempt to downplay the shrinking of Arctic sea ice. They have two tactics for doing so:

  1. claiming that the decline in Arctic sea ice is counterbalanced by growth in Antarctic sea ice. Not only is this claim of  equivalence extremely misleading, currently Antarctic sea ice extent is not showing any increase versus the 1981-2010 average, thus even the misleading equivalence claim goes away (at least for this month)
  2. utilizing the variability of sea ice melt on a year by year basis by making comparisons of a year with extremely low extent to the current year. The clearly downward trend in Arctic sea ice extent can be obfuscated via cherry picking dates due to annual variability.

Arctic Versus Antarctic Sea Ice Extent

As shown in the images below, as of August 2015, Arctic sea ice is well below average extent, while Antarctic sea ice extent is about average. However, even in years when Antarctic sea ice is of above average extent, claims that they are offsetting are incorrect, as explained in posts from The National Snow & Ice Data Center and Skeptical Science. And a critical reason why they are not counterbalancing is the impact the warming arctic is having on the weather in the Northern Hemisphere. A number of researchers are conducting studies to determine if the weird winter weather in recent years resulting from the unusually wavy jet stream is due to reduced ice extent in the Arctic.

As illustrated in the above image, currently Arctic sea ice extent is more than 1.5 million kilometers below the average during 1981-2010. (Although not as low as during the record setting year of 2012).

The above image shows that as of August 2015, Antarctic sea ice has returned to average levels. Thus, the claims of climate science deniers that the sea ice extent at the two poles are offsetting have completely melted away.

Here is an example of the sea ice myth propagated by climate science deniers:
Arctic sea ice loss is matched by Antarctic sea ice gain. In fact, the global sea-ice record shows virtually no change throughout the past 30 years, because the quite rapid loss of Arctic sea ice since the satellites were watching has been matched by a near-equally rapid gain of Antarctic sea ice. Indeed, when the summer extent of Arctic sea ice reached its lowest point in the 30-year record in mid-September 2007, just three weeks later the Antarctic sea extent reached a 30-year record high. (Chris Monckton) 
Another prime example of a climate science denier mangling facts is provided by James Taylor of the Heartland Institute. In particular, note his use of the word "modest" in the quote provided below. Sorry, Mr. Taylor, but the loss of over a million square miles of Arctic sea ice is anything but "modest".
The alarmist assertion that polar ice sheets are melting is simply false. Although alarmists frequently point to a modest recent shrinkage in the Arctic ice sheet, that decline has been completely offset by ice sheet expansion in the Antarctic. Cumulatively, polar ice sheets have not declined at all since NASA satellite instruments began precisely measuring them 35 years ago.
 As shown in the above images, the claims by climate science deniers that Arctic and Antarctic sea ice extents are counterbalancing or that the decline is Arctic sea ice is "modest" are false.

Cherry Picking Data

In 2013, it was widely reported by climate science deniers that Arctic sea ice extent had increased by 29%. This was indeed true. But what made reports of the recovery of the Arctic sea ice extent misleading was that it was based on cherry picking a year with record low extent (2012) as the baseline year. 

A quick glance at the image below makes obvious that Arctic sea ice is not recovering, simply that the decline is variable from year to year. While the record low for Arctic sea ice extent in 2012 has not been matched during the last 3 years, based on the well established trend, a new record low is almost certain to be established within the next few years. Climate science deniers are notorious for comparing current year results to the data from record setting years, and thus trying to obfuscate the clearly established trends. Sadly, arctic sea ice is not recovering. In fact in 2015, it is likely that before the end of the melt season both the Northwest and Northeast passages through the Arctic will be ice free and navigable without the need for an icebreaker.


We live in a warming world. Climate science deniers go through all kinds of contortions to try to dispute this conclusion. But their clams that declining Arctic sea ice is "warmist" propaganda is currently completely invalid

Related Posts

Will Arctic Northeast Passage Be Ice Free By Late July in 2015?

Sea Level Rise May Be Accelerating in 2015

Cutting Through The Global Warming Debate: It's the Rising Sea Level, Stupid!

Monday, July 20, 2015

Will Arctic Northwest Passage Be Ice Free By Late July in 2015?

The search for a shorter path from the Atlantic to the Pacific (and vice versa) captivated 19th century explorers. Avoiding the long and treacherous trip around the horns of Africa and South America offered huge saving in the time and cost of a voyage. However, from a navigation standpoint, the discovery of the Northeast Passage and John Rae's 1848 discovery of the Northwest Passage had little practical value during the 19th Century, as ice blocked the routes.

Remarkably, it appears that the Northeast Passage may be ice free by the end of July 2015, based on images posted by the National Snow and Ice Data Center. The early melting of the sea ice that usually blocks the Northeast Passage is a result of the warming of the Arctic. If the sea ice along the Northeast Passage continues to melt as rapidly as it has over the past week, it may be the earliest in the summer during recorded history that this route has been ice free and navigable without the need for an icebreaker.

Northeast Passage in Red

According to Jeff Masters "A large area of high pressure that has set up shop north of Alaska is expected to persist for the remainder of July, and is likely to bring sunny skies and a warm flow of air into the Arctic that will lead to rapid ice loss in the coming weeks"

As shown in the image below, the Northeast Passage is on the verge of becoming ice free (as of July 19, 2015).

 Sea Ice Extent

Regardless of whether 2015 is a record setting year for earliest opening of the Northeast Passage, the rapid ice melt provides another indication that we live on a warming planet. It may only be a matter of decades before the Northwest and Northeast Passages through the Arctic are navigable from August through October.