Folks,
I am a global warming skeptic. This term, however, requires some explanation. I believe in climate change. The climate is always changing. However, I don’t think it is clear that the world has been getting warmer in the last decade. I also am not convinced that humans are the main drivers of whatever climate change has occurred. The following explains why.
Point 1: For the Last 12 years the World Not Getting Warmer
The global warming scenario that exists today is that human emissions of carbon dioxide are the main reason that the climate is warming. So, it is natural then to ask, is the climate really warming? One look at USA Today’s cover story “Why You Should Sweat Climate Change” on March 1 would appear to settle the story. Just look at Figure 1 below.
Figure 1. Graph from USA Today March 1, 2013.A quick scan of the graph shows 55.34°F last year and 50.56°F in 1895, a 5° increase. Wow! A little closer analysis reveals that these temperatures are individual data points. If you look at the years 1900 and 2010, you get 53°F for both years, essentially no change. The thick red line is the long term trend and admittedly it increases from about 51.3°F to about 53°F in the 117-year period.
Note the icon in the upper right corner. It shows the globe with a dramatic upward trendline. However, this causes you to now note that this graph is for US temperatures, not world temperatures. What was the world temperature like? As this thought crosses your mind, you remember that 2012 brought Europe its coldest winter in recent memory. So you go on the internet and find out that 2012, for the world, was the ninth hottest year on record. Scary. But then you think, “Wait a minute, that means that eight years were hotter.” So you wonder, what do the last 10 or so years look like for world temperatures. The graph is below in Figure 2:
Figure 2. World Temperature 2001-2012. Graphed by Dr. Ron
Note that for the past 12 years, the trend is flat (actually a little down). Where are all of the headlines sharing this important information? So it is not clear that the world is continuing to get warmer.
Am I the only one that finds it troubling that the media seem to universally tout the scary stories about global warming, but don’t seem to mention obvious counterpoints such as the graph above? This information is profoundly important.
Point 2: In the Past, Nature Along has Delivered Stunning Climate Change by Itself
I am writing this post from my home Woodstock, VT. I look out my window and view two beautiful, large rocks, each about the size of a house. These monoliths were likely left as the glaciers in the last ice age retreated, these rocks probably originated in Quebec. Woodstock was under thousands of feet of ice during the last ice age, Canada was completely under ice. New York State’s Long Island is a glacial terminal moraine. The extent of the ice coverage is shown in Figure 3. However, the forces of nature alone, raised the temperature of the earth by 12°C(with no help from mankind), melting the glaciers and allowing me to live in the Green Mountain State (Vermont = Ver (green) mont = mountain, in French.)
Figure 3. The Extent of the Ice Coverage in the Last Ice Age http://www.iceagenow.com/
The natural processes that caused the warming are many. They include the precession of the earth on its axis, variation in the output of the sun, changes in the ocean and atmosphere, and others. These processes have resulted in the past temperature changes as shown in Figure 4.
Figure 4. Temperature of the earth in the past 800,000 yearsThis figure shows as much as a 20°C (36°F!) temperature swing produced by nature alone. The change in world temperature between 1900 and 2010 would be about as thick as the line in this figure.
I find the proposition that the main driving force in global warming (if it is occurring) being human produced CO2 alone is hard to accept, when we see what mother nature has given us in the past. It would be similar to someone taking the position that the only thing that affects stencil printing quality is the stencil. When others point out that it might be the solder paste, or the print head, or separation speed, etc., they are shouted down as being unscientific.
Point 3: It was Warmer in the Middle Ages than Today
The United Nations commissioned a panel to study climate change in 1988. The Intergovernmental Panel on Climate Change (IPCC) was established. In 1990, the panel came out with an assessment of past world temperatures as shown below in Figure 5. The estimating of temperatures before the mid 1800s is difficult due to lack of records and thermometers before this time.
Figure 5. The First IPCC assessment of world temperatures, 800AD to presentThere is some argument that the Medieval Warm period and Little Ice Age were local events, however they clearly existed and profoundly affected much of the Northern Hemisphere. But more recent temperature IPCC plots lose them, as seen in Figure 6. The Medieval Warm Period enable the Vikings to settle in Greenland and red wine to be grown in England. When the Little Ice Age came, the Vikings had to leave and England has not been as warm since.
Figure 6. Third IPCC temperature assessment. Note the Medieval Warm period and Little Ice Age disappear. Because of the abrupt change in temperature after 1900, this graph has earned the moniker, The Hockey Stick Graph.
The controversy over the Hockey Stick graph is interesting reading and is the source for Figures 4-6.
In 2003, MacIntyre and McKitrick presented a detailed criticism of the IPCC 3rd Assessment’s Hockey Stick Graph in Figure 6 . I find their criticism compelling.
I could go on and on, but to summarize why I am a global warming skeptic:
- For the past decade the world has not gotten warmer
- Natural forces overwhelm CO2 as a driving force for climate change
- Sloppy science is behind the hockey stick graph
Please share your science- and fact-based comments.
Cheers,
Dr. Ron
Ask any climate scientist: Man-made carbon pollution is the cause of global warming. The hockey stick graph has been proven over and over again. This is the hottest it has been in a very long time. http://clmtr.lt/cb/qgp0Ww
Your Point 1 is incorrect, because a) you are considering only the temperature of the atmosphere, not the temperature of the oceans, ice, and land; and b) you are cherrypicking too short a time period. “Global warming” does not mean every year gets warmer than than the previous year. The IPCC does not even project rises year to year; instead it projects temperatures averaged across 20 year periods, and projects that successive 20-year periods will–usually, not always–have greater average temperatures. For details see here, here, and here. In each of those pages I’ve linked, you don’t have to trust those pages’ authors’ interpretations. Every contention in those pages is backed up with one or more citations of peer-reviewed scientific literature, which you can get to simply by clicking those citations’ links.
Your Point 2 is irrelevant. Of course climate changed from non-human influences (“forcings”) before humans came along, and continues to change due to non-human influences even now. Humans add other forcings. The relevant question is to what extent the human forcings are causing global warming and the resulting other changes in climate. Climatologists have not and do not simply assume that whatever changes they cannot explain by natural forcings are due to humans. Instead, the empirically derived, experimental knowledge of the radiative physics of greenhouse gases were used to project human-caused global warming from greenhouse gas emissions; those projections were made at the turn of 19th to 20th centuries, decades before it was even technically possible to measure global temperature trends. For a thorough explanation of that history, see Spencer Weart’s Discovery of Global Warming. For a short video summary of successful and unsuccessful climatology projections, watch Ray Pierrehumbert’s 2012 AGU lecture>/a>. Those projections have been refined over decades, and are quite well enough accurate to tell us we’re in trouble. The natural forcings you mentioned were major up through the early 20th century, but since then have been either neutral or had a cooling influence. Since at least 1960, greenhouse gases have been the dominant forcing. There also are a bunch of human fingerprints all over the current warming.
My last comment has broken HTML (sorry). Ray Pierrehumbert’s video is one link. There is a different link to a different page on a different topic, starting with the subsequent words “quite well,” and you can get there by clicking those words despite the appearance that it is part of the same link as the one to Ray’s video.
Your Point 3 is irrelevant, for the same reasons I listed in my previous comment that your Point 2 is irrelevant; the mere fact that the climate has changed before is not relevant to why the climate is changing now. Also, the first graph you show in Point 3 was only for central England, not the whole world. Since the first IPCC report, global data has been gathered, because science marches on. The Medieval Warm Period, and indeed the entire hockey stick, are not relevant to the radiative physics of greenhouse gases. (An aside: The hockey stick is robust, having been replicated by many different people using many different methods and many different sources of data. It has even been extended to earlier dates, so the bigger picture is a wheelchair.) Carbon dioxideis the key to our current warming.
Your implications about Greenland and English wine also are off base.
Warming since around 1960 cannot be due to the Sun, because the Sun’s activity has been flat or trending down since then (averaged across the Sun’s 11 year cycles).
The precession of the Earth’s axis is only one portion of the Milankovich cycles. Milankovich cycles operate on time scales far, far too long to be causing our currently dramatically rapid warming, and to the extent they are operating, they are trying to cool the Earth, not warm it. So human-caused warming forcing is overwhelming that slight natural cooling forcing.
This meme – the world has not been warming lately – keeps flying around the internet. It’s a great example of a double (yes, double) cherry pick. Pick a date (many like to use 1998) that specifically skews the data. Then pick a data series – say, surface air temps – that happens to comply with your view of what you’d like to see, no upward trend.
Then claim that this one data series from one date (in your case, 10 years?!?!? C’mon, you’re a self claimed scientist; climate is a long-term process) suddenly calls into question the decades of research and thousands of scientific papers on climate change.
I can do it, too!
How about 1995 and surface air temps? – Bingo! global warming
1989 and sea level – Bingo! global warming
1992 and ocean heat content – Bingo! global warming
2000 and Arctic sea ice extent – Bingo! global warming
I could fill pages with these. In fact, in 2007 the IPCC looked at 29,000 data series. 29,000! 29,000 biological and physical data series that could be affected by a changing climate. More than 90% were consistent with the approx. 0.8C temp rise observed.
The data you show above. Is it some sort of secret? Or do you think that climate scientists are familiar with it? I’ll assume they are familiar with existing public climate data, in which case, why do they continue to warn us that we are in danger? What do you know that they do not?
Ask any climate scientist (which you are not, according to your bio above): Man-made carbon pollution is the cause of global warming and the climate continues to warm unabated. http://clmtr.lt/cb/qgp0t2
Lastly, you should familiarize yourself with the Foster and Rahmstorf paper from 2011, which removed the El Nino/La Nina and other non-CO2 forcings from the temperature data. It showed a continued upward trend, contrary to your assertion that climate change has stopped or paused.
Jeers for Dr. Ron! Cheers for Tom Dayton and Steve O for easily showing how wrong Dr. Ron is! Ask any climate scientist: Man-made carbon pollution is the cause of global warming. http://clmtr.lt/cb/qgp0tz This isn’t even debatable anymore. The need to act now is not debatable. The only thing left to discuss is what to do next to try to slow the effects of man made climate change. Pieces like this blog by Dr. Ron are nothing more than rehashes of talking points that fossil fuel companies and climate change denialists have been trying to shove down our throats for years. We should have started to act on these problems in the 60s. We were late but should have started in the 70’s under Carter. The time for this faux “debate” is over. Stop stretching the truth for your own gains and start to drop some reality.
Hi Dr. Ron,
To your first point; “For the past decade the world has not gotten warmer”
This is a false statement. A true statement would be;
For the past decade the surface and troposphere show no statistically significant warming trend.
Since 1984, satellitees havee been measuring Earth’s energy flux. The energy net flux has been consistently positive, year after year, more energy coming in than going out. The temperature of surface and troposphere represent <5% of the Earths heat sinks and therefore highly variable and influenced by internal variability. Because of this variability, a minimum of 30 years is necessary to establish a statistically significant trend. Since the past decade was the warmest decade on record, it is quite a stretch to say the warming trend has stopped or reversed.
Further to Point 1, the Earth’s warming has been *faster* in the past 15 years than in the previous 15, when you consider the whole system instead of just the very noisy atmosphere. Since you are at a university, you easily can get ahold of this new paper by Balmaseda, Trenberth, and Källén (2013). Other folks can see a summary here.
Sooooo we can dismiss that the entire world went through ice ages and the earths temperature was stable since the dawn of time and humans are now the cause of global warming. That totally makes sense. Thanks for clearing that up for me. We have only been monitoring the temperatures of oceans and climates for a brief moment in time compared to the history prior to data collection. Don’t plants and animals go extinct without human intervention? I believe thats been proven. Why is it so hard to believe in the natural earth cycles? Eventually we will have another ice age that some form of human cause will be blamed on too. Global warming is a money making scheme just as oil and other resources are.