Marcott et al (2013)

A study by Marcott et al that reconstructed the Earth’s climate over the past 11,300 years using data gathered by various proxies at 73 locations globally. The findings of this study showed that the Earth had been gradually cooling over the past 5,000 years up until about 100 years ago, when it began to warm. The Holocene era, the studied time period, experienced gradual climate changes which allowed for the flora and fauna to adjust. The more recent changes though, are more rapid and may exceed the hottest period during the Holocene period. The recent warming is due to human activity, not natural causes. This is evident especially when examining the fact that because of the Earth’s orientation, the Norther Hemisphere should be experiencing cool summers as part of a cooling trend, which is not occurring. It is projected that the temperature will increased anywhere from 2 degrees to 11.5 degrees Fahrenheit by the end of this century.  

Three key findings of the study include the fact that the 1.3 degree cooling that occurred over the last 5,000 years was reversed in just the past 100 years, and the temperature will continue to rapidly increase. Another key finding is that with the natural changes of the Earth the Northern Hemisphere was projected to experience intense cooling over the next few thousand years but most likely will not because of the increase output levels of carbon dioxide and continued warming. A third finding is that this past century is an anomaly because we have not experienced this level of warming since the most recent ice age over 11,000 years ago.

Figure 1: Temperature Anomaly for previous 2,000 and 11,000 years.

Image Source: http://cdn.antarcticglaciers.org

These two graphs temperature data for the Earth over the Holocene period. The figure on the left shows the same data as the figure on the right, zoomed in to 2,000 years. These graphs illustrate the warming and gradual cooling experienced during the Holocene period with the rapid jump in temperature over the past 100 years. As illustrated in the graph on the right, the current temperature is very close to the warmest time of the Holocene period.

According the Michael Mann of Pennsylvania State University, the main conclusion of this study by Marcott et al is “the rate of warming appears to be unprecedented as far back as the authors are able to go (to the boundary with the last ice age). And the rate of warming appears to have no analog in the past”. The warming that we are experiencing, and the rate at which it is occurring is not by means of nature as it has been in the past. With increased human activity and output of carbon dioxide among other greenhouse gases into the environment, the Earth is going through rapid changes that we have not seen before.

Concerns that Robert Rohde, the chief data analyst behind the Berkeley Earth Surface Temperature project, has are that in the study they relied too heavily on their proxy data which was spread out in time. This can blur or obscure the fluctuations in the data. Because of this he thinks that, “we can’t use the analysis of Marcott et al. to draw any firm conclusions about how unique the rapid changes of the twentieth century are compared to the previous 10,000 years.” Ultimately he recognizes the impact that the findings have in building upon current knowledge as well as assisting in future studies, but he urges the use of caution when comparing their findings and current events.

According to Richard Alley, of Pennsylvania State University, the big-picture messages from this study are, for one, “Our high assessed confidence that the recent warming is mostly human-driven, and that the costs will become large if the warming becomes large, do not primarily rest on how much warmer or colder today is than some particular time in the past, or even on how fast the recent changes are relative to those in the past.” Meaning scientists aren’t conducting these studies and saying that because today is hotter than it was 1,000 years ago means that we’re experiencing global warming; they look at the many factors that go into what climate is and what the climate is and has been around the world. Another takeaway is, “Whether the past was naturally warmer or cooler than recently, and whether the changes were faster or slower than recently, are of great interest to climate scientists in learning how the climate system works, including the strength of feedbacks.” So while we cannot look at 1 day or 1 year for comparison, it is still extremely important and valuable that scientists continue to study the past in attempts to understand how climate works that that we may appropriately prepare for the future.

Roger Pielke, professor at the University of Colorado, addresses in a blog post that the media made some mistakes when covering this study. There has been various coverage of the study that explains the resulting temperature data as fitting into the “hockey stick” analogy. The coverage explains that there has been a sharp increase in temperature in the past 100 years, the blade of the stick. Pielke explains this is wrong. He explains that the 20th century data is “not statistically robust” therefore there can be no “blade” for Marcott et al’s study.    

Ray Bradley

After reading Ray Bradley’s transcription of a lecture given in 2009, these are two questions that I would ask him if I could, and why.

Because of the ways in which data is collected (ice cores, tree rings, reefs, lakes) are there areas of the world that do not have that kind of data (data that looks back thousands of years)? For example, in deserts, how is/could data be collected there?

• I would hope that he would explain where in the world there are deficits of data and why. I also would expect him to say whether or not there is a way to collect data in those places, and why they have yet to do so. I want to know if this is something that scientists are concern about or think about, or if they think that they have all this data collection under control. Do they think that they’re getting information from enough of a variety of places? I think a scientist’s perspective on this is the most important, because it is their work.

Scientists have all this information about the ways in which our climate is changing, and we know that there needs to be some switches away from coal as an energy source, but what can I do? What can someone who isn’t a political figure or millionaire do to help protect the Earth against global warming?

• I can’t say that I have any idea what he would say in response to this. After learning about what he is describing, I want to know how I can productively use this information. I want to know his answer because knowing all this is well and good, but if I can’t do anything by myself, I want to at least know how to help get this information out there.

Jeff Tollefson

Jeff Tollefson is a reporter and writer for Nature, a weekly science journal. He has previously worked for Congressional Quarterly as well as the Billings Gazette. He has won many accolades as a science reporter. As far as reliability goes, I would say that I trust a scientific journal but am skeptical because he is not a scientist. After reading one of his articles, "The Case of the Missing Heat" I have to say that I'm not persuaded to thinking that we are not experiencing global warming. Although he claims that skeptics as well as scientists are convinced that they previously overestimated the severity of the effects of greenhouse gases, I think he and those supposed people are focusing too too short term. While he appears to make valid points, it is my opinion that he is further illustrates the "skeptic" view of global warming that is shown on the figure below.

Figure 1: Skeptics and Realists Views of Global Warming

Image Source: http://www.jimharris.com/wp-content/uploads/2012/02/skepticsvrealists_500.gif

Global Warming and Weather

If I were to answer the question, “what are the connections between climate change and the extreme weather we’ve been having?” I would have to use Kevin Trenberth for help. Kevin Trenberth is a scientist at the National Center for Atmospheric Research. He’s spent a lot of time studying climate variability. More recently he studies the global water cycle and how it’s responding to climate change. He has written many scientific reports as well as currently leading a world climate research program. In his talk at the 2013 Seattle Science Festival he explained that because of the increase in temperature over the past century the water cycle is actually speeding up. Water is evaporating more quickly and forming into clouds which become more dense more quickly, causing intense rain. This is also the reason for drought in many places; water has evaporated quickly with higher temperatures, so if there is no moisture in that area the drought is more intense. He continued to explain that because there is more evaporation there is more moisture in the atmosphere, meaning heavier rains, which is what is happening recently. Furthermore as Richard Keer stated in his article in Science Magazine “In the Hot Seat”, that, “global warming has increased the chance of extreme events” but there is not one event in particular that can be directly linked with global warming alone.

I think an excellent but simple analogy to help explain this is one that Trenberth used during his talk in Seattle. He related the Earth and global warming to a person taking a hike in the Summer. If that person fails to bring water with them, they will only be sweating and not taking in any moisture, which could lead to a heat stroke. If the Earth quickly evaporates without rain, we see extreme droughts. Another analogy that was mentioned in Dan Satterfield’s article “Welcome to the New Climate” relates the weather and climate to a baseball player taking steroids. He explains, “Can you say that he hit a home run because of the steroids? No, he likely hit quite a few before he was on steroids. The steroids just made it more likely he would knock the ball out of the park. Increasing greenhouse gases make it more likely that we will see heat waves like this.”

If you'd like to watch all of Kevin Trenberth's talk at the Seattle Science Festival click here!

Fixing the Communications Failure

These questions address the topics discussed in D. Kahan's Fixing the Communications Failure article.

• What is cultural cognition?
• Cultural cognition is the term for influence of an individual’s or group’s values on risk perception. For example, a person’s perception may be swayed in their favor regardless of validity. Image two people watching their favorite teams in an important game. Each might “see” more violations being done to their group/by their opposing group, even though they are watching the same game.
• How does protective cognition manifest itself in the context of climate change science?
• In regards to climate change, cultural cognition and protective cognition can cause people to manipulate information in support of their own previous beliefs as well as altogether dismiss ideas because they would hinder or negatively affect something that they enjoy. People put up blocks to what they don’t want to hear, and weigh information that supports their ideas more heavily.
• Explain the two specific techniques suggested for improving scientific communication.
• Two methods of improving scientific communication are to present information that affirms beliefs rather than threaten them, and to present that, correct, information in a variety of ways from a diverse set of experts. This means that information should be presented by experts from all fields, so that people can relate and trust them, as well as see that there are many people who are all on the same page. The information they present should be presented in a way that people can have relevancy too and in a way that people do not feel threatened. When people’s ways of life are threatened they reject those notions, but if they feel that the information can enhance or fit into their current ways/beliefs they are more likely to accept it.
• What, unfortunately, is the reality of most scientific communication.
• What usually has and does happen is that when information is given, it is given in full force out to the public. This means that regardless of validity, it has the potential to go against someones current views, hinder their current ways, and people will reject the information.

Brilliant or Crazy?

"The Most Terrifying Video You'll Ever See"

This gentleman created a video that quickly broke down our (extreme) outcomes if we act or do not act on global warming (which he claims may or may not happen). He used a decision grid to show our possible outcomes. Although he claims that we cannot be sure that global warming is happening, he raises a good point in that the costs of acting and nothing happening much outweigh the costs of not acting and global warming hitting us head on. So even though I disagree some of his thoughts, for example I believe that global warming is already in full swing, I agree that we need to do something about rather than not. I think this video can really speak to people who are skeptical about global warming and who do not want to “waste money” trying to counter it with renewable resources, nuclear power, etc. As far as if I think he’s brilliant or crazy? I think he’s something in between.  

A Debate on Nuclear Power

TED Talk

This is a video of a TED talk that features Stewart Brand and Mark Jacobson in a debate on nuclear energy. Both men bring up valid and very interesting points on nuclear energy as well as renewable sources such as wind and solar. A few members of the audience also weigh in briefly on either side of the debate. In the beginning the host asks, by a raise of hands, who is for and who is against nuclear power: the results are about 75:25 for. At the end he asks again and some people change in both ways. Watch and see if this debate influences your thoughts at all!

Video Source:

http://www.ted.com/talks/debate_does_the_world_need_nuclear_energy.html via Carsten Braun's posting for a class assignment

                      

Seen Something, Saying Something

Micheal Mann, who wrote the article If You See Something, Say Something is a scientist whose work has been sucked into the current “climate wars”, as he put it. James Hansen is another scientist who has protested and become an activist for reducing our carbon emissions. Stephen Schneider, now passed, had quite a different than Hansen. He believed that scientists should not be compromising their objectivity by becoming involved in the political aspects of climate change.

Though these three scientists have different ways of getting their knowledge about climate change out, they have all “seen something” and have or are “saying something”. They are all on the same page about the urgency of climate change and the need to do something before it’s too late.

Richard Alley

Richard Alley is a professor at Penn State. He works in teaching, science, and public outreach. He studies ice sheets and analyzed ice cores to show climate change occurs. He is also an author The Two Mile Time Machine and hosts a PBS show “Earth, the Operator's Manual”.

After watching him in a talk at the Seattle Science Festival in 2013 (Click here to watch!) I really enjoyed how he described how science changes when new things are discovered and the world changes but sometimes “zombie” ideas come back and dominate. Those zombies could be hundreds of years old, ideas that have since become irrelevant but people “wake them up”. I thought his analogy and description of that process of people bringing up old scientific ideas and them having to work so hard to “put them back to sleep” was really clear and understandable.

Another thing I took away from this talk is how he analyzed the graph that shows how the world has warmed. He broke down his life to show how that could look as if we are in global cooling. His direct attack on those kind of interpretations is not only eye opening but makes you think about what other kinds of statistics and graphs have been cut down by the media and the government to show what they want to show.

Something that I thought was really powerful was his quote, “If we burn before we learn, we leave our grandchildren without a safety net”. He continues on to say that “if we burn while we learn” we can make the world a better place, we can give the next generations a safety net. He reiterates that the resources are there, even Lincoln saw that we have forces to be tamed (wind). We just have to take advantage now.

If I could ask him one question I think it would be:

What can I, one person, do to help Global Warming, to help the world “learn before we burn”?