Extreme Space Weather Event #23072012

You may have seen some dramatic headlines in the news last week: “‘Extreme solar storm’ could have pulled the plug on Earth” (Guardian); “Solar ‘superstorm’ just missed Earth in 2012” (CBS); “How a solar storm two years ago nearly caused a catastrophe on Earth” (Washington Post blog). Also see this Physics Today article, which was published online today and reviewed the press attention to the event.

Though journalists and editors often write hyperbolic headlines, the danger from solar storms is very real, though extreme ones are as rare as massive earthquakes. When you think of solar flares and eruptions threatening humans, it may evoke Stanislaw Lem’s Solaris or the Doctor Who episode 42, but at least our sun isn’t sentient (as far as we know)!

A less threatening solar storm on the Sun

The solar storm in question occurred two years ago on 23 July 2012, and the media reported on it following a NASA public-information release and accompanying four-minute YouTube video (see below). It seems that those of us who live on Earth and use electronic technology were lucky that this was a near miss. The threat of solar storms is also relevant to “space security”, which I wrote about in a previous post.

The paper itself was published last fall in the Space Weather journal by Daniel Baker, of the Laboratory for Atmospheric and Space Physics at the University of Colorado, and six colleagues from NASA, Catholic University, and the University of New Hampshire. Its full title is “A major solar eruptive event in July 2012: Defining extreme space weather scenarios,” and here is their abstract (abridged):

A key goal for space weather studies is to define severe and extreme conditions that might plausibly afflict human technology. On 23 July 2012, solar active region 1520 (141°W heliographic longitude) gave rise to a powerful coronal mass ejection (CME) with an initial speed that was determined to be 2500 ± 500 km/s [5.6 million miles/hr!]… In this paper, we address the question of what would have happened if this powerful interplanetary event had been Earthward directed. Using a well-proven geomagnetic storm forecast model, we find that the 23–24 July event would certainly have produced a geomagnetic storm that was comparable to the largest events of the twentieth century…This finding has far reaching implications because it demonstrates that extreme space weather conditions such as those during March of 1989 or September of 1859 can happen even during a modest solar activity cycle such as the one presently underway. We argue that this extreme event should immediately be employed by the space weather community to model severe space weather effects on technological systems such as the electric power grid.

The solar storm missed the Earth but hit NASA’s STEREO-A spacecraft, which was safely outside the Earth’s magnetosphere and was able to measure and observe the approaching CME, a billion-ton cloud of magnetized plasma. “I have come away from our recent studies more convinced than ever that Earth and its inhabitants were incredibly fortunate that the 2012 eruption happened when it did,” says Baker. “If the eruption had occurred only one week earlier, Earth would have been in the line of fire.” According to the simulations in their follow-up paper by Chigomezyo Ngwira et al., had the 2012 CME hit the Earth, it could have produced comparable or larger geomagnetically induced electric fields to those produced by previously observed Earth-directed events and would have put electrical power grids, global navigation systems, orbiting satellites, etc. at risk.

Pete Riley, a physicist at Predictive Science Inc., published a paper in 2012 in the same journal entitled “On the probability of occurrence of extreme space weather events.” He analyzed historical records of solar storms, and by extrapolating the frequency of ordinary storms, he calculated the odds that a Carrington-class storm (which occurred in 1859) would hit Earth in the next ten years is between 8.5 and 12%!

NASA has calculated that the cost of the 2012 CME hitting the Earth would have been twenty times the devastation caused by hurricane Katrina—on the order of $2tn. The storm would have begun with a solar flare, which itself can cause radio blackouts and GPS navigation failures, and then it would have been followed by the CME a few minutes later, potentially causing widespread havoc with global technological infrastructure. Anything that uses electricity, including water supplies, hospital equipment, and radio and television broadcasts could be shut down. How do we prepare as a society for an event like that?

For Traveling Scientists: Praise for Trains

And now for something completely different! I’d like to make the case that we should take intra-city and inter-city trains more often. (I mean this especially for Americans, since trains are already more popular and more advanced in many other countries.) As some of you know, I like riding trains, and I even thought of writing an “ode to trains,” but though I enjoy poetry—which is virtually required of me as a half-Persian—I don’t think I write it particularly well. One of my first memories as a boy was riding a train in Colorado and sticking my head out the window, only to get a face full of smoke. I’m a fan of blues, folk, and jazz music too, and many musicians (such as Woody Guthrie, Muddy Waters, Johnny Cash, Bob Dylan, Joan Baez) have sung train songs. This post is also partly inspired by an interesting and entertaining article by Kevin Baker in the July 2014 issue of Harper’s magazine.

I’m motivated by the fact that many people, and especially scientists, frequently travel long distances. Many astronomers and astrophysicists travel to conferences, workshops, and meetings as well as to telescopes. Occasionally it’s possible to interact or participate in meetings by videoconferencing and to use telescopes with “remote observing,” but it’s often the case that travel can’t be avoided, and as I’ve written here before, it’s important for junior scientists to present their work and engage in networking in person to help to advance their careers. Although most telescopes and observatories are constructed to be environmentally friendly, it is long-distance travel that results in very large “carbon footprints.”

My carbon footprint has been particularly large this year, and I hope to do better next year. I plan to begin by considering taking a train from southern California to Seattle for the annual meeting of the American Astronomical Society (AAS) in early January. Long-distance travel is also an issue being taken up by the AAS Sustainability Committee.


If you’re wondering, this trip would take most of a weekend, but it would offer nice views of the Pacific coast and the trains have free wireless internet too. It looks like the Coast Starlight line takes about 34 hours to travel from Los Angeles’s historic Union Station (pictured below) to Seattle’s King Street Station, but it covers a distance of 1377 miles (2216 km)—nearly the distance between the borders of Mexico and Canada.


We should keep in mind that, after walking and biking, trains are the most efficient way to travel. Amtrak, the US’s publicly funded railroad service, expends an estimated 1,600 BTUs of energy per passenger per mile, while buses use 3,300, planes use 2,500, and cars use 3,900! If we seriously want to use less energy and substantially reduce carbon emissions, we should travel by train much more often. From the perspective of climate change, although “carbon offset” programs have been attempted (with very limited success so far), nothing beats not emitting greenhouse gases in the first place.

Americans used to travel all the time by train, but with the triumph of the auto and aviation industries and the increased popularity of cars (with subsidized gas prices) and planes for long-distance travel, Amtrak ridership dropped to 16 million in 1972. Fortunately, ridership has doubled since then, and President Obama in 2011 committed his administration to a vision of giving “eighty percent of Americans access to high-speed rail within twenty-five years.”

The US needs to upgrade and expand its train lines and cars. Europe and China have trains that are at least twice as fast as ours, and Japan’s new Shinkansen bullet train goes 200 mph! Americans sometimes complain that the country is too big for trains, but China shows that it’s certainly possible. I think we need to push for high-speed trains, especially in California and the East Coast but also within the country, such as the California Zephyr line that links the Bay Area, Denver, and Chicago. This will take a lot of investment and time, but it will be worth it. Although the US auto industry has suffered in recent years, improving and expanding the rail system certainly would help the “green economy” and create many “green jobs”. And we should keep in mind that annual federal highway and aviation subsidies are currently gigantic ($41.5 and $16 billion in 2013, respectively) compared to Amtrak subsidies ($1.6 billion). The planned California high-speed rail will cost an estimated $68 billion to construct, but it will be built over many years.

AAAS Symposium in Feb. 2015: Cutting-Edge Research with 1 Million Citizen Scientists

[This is an expanded version of a post I wrote for the Galaxy Zoo blog.]

Some colleagues and I successfully proposed for a symposium on citizen science at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Jose, CA in February 2015. (The AAAS is the world’s largest scientific society and is the publisher of the Science journal.) Our session will be titled “Citizen Science from the Zooniverse: Cutting-Edge Research with 1 Million Scientists.” It refers to the more than one million volunteers participating in a variety of citizen science projects. This milestone was reached in February, and the Guardian and other news outlets reported on it.


“Citizen science” (CS) involves public participation and engagement in scientific research in a way that educates the participants, makes the research more democratic, and makes it possible to perform tasks that a small number of researchers could not accomplish alone. (See my recent post on new developments in citizen science.)


The Zooniverse began with Galaxy Zoo, which recently celebrated its seventh anniversary, and which turned out to be incredibly popular. (I’ve been heavily involved in Galaxy Zoo since 2008.) Galaxy Zoo participants produced numerous visual classifications of hundreds of thousands of galaxies, yielding excellent datasets for statistical analyses and for identifying rare objects. Its success led to the development of a variety of CS projects coordinated by the Zooniverse in a diverse range of fields. For example, they include: Snapshot Serengeti, where people classify different animals caught in millions of camera trap images; Cell Slider, where they classify images of cancerous and ordinary cells and contribute to cancer research; Old Weather, where participants transcribe weather data from log books of Arctic exploration and research ships at sea between 1850 and 1950, thus contributing to climate model projections; and Whale FM, where they categorize the recorded sounds made by killer and pilot whales. And of course, in addition to Galaxy Zoo, there are numerous astronomy-related projects, such as Disk Detective, Planet Hunters, the Milky Way Project, and Space Warps.


We haven’t confirmed the speakers for our AAAS session yet, but we plan to have six speakers from the US and UK who will introduce and present results from the Zooniverse, Galaxy Zoo, Snapshot Serengeti, Old Weather, Cell Slider, and Space Warps. I’m sure it will be exciting and we’re all looking forward to it! I’m also looking forward to the meeting of the Citizen Science Association, which will be a “pre-conference” preceding the AAAS meeting.

Comparing Models of Dark Matter and Galaxy Formation

I just got back from the “nIFTy” Cosmology workshop, which took place at the IFT (Instituto de Física Teórica) of the Universidad Autonoma de Madrid. It was organized primarily by Alexander Knebe, Frazer Pearce, Gustavo Yepes, and Francisco Prada. As usual, it was a very international workshop, which could’ve been interesting in the context of the World Cup, except that most of the participants’ teams had already been eliminated before the workshop began! In spite of Spain’s early exit, the stadium of Real Madrid (which I visited on a day of sightseeing) was nonetheless a popular tourist spot. I also visited the Prado museum, which had an interesting painting by Rubens involving the Milky Way.


This was one of a series of workshops and comparison projects, and I was involved in some of the previous ones as well. For example, following a conference in 2009, some colleagues and I compared measures of galaxy environment—which are supposed to quantify to what extent galaxy properties are affected by whether they’re in clustered or less dense regions—using a galaxy catalog produced by my model. (The overview paper is here.) I also participated in a project comparing the clustering properties of dark matter substructures identified with different methods (here is the paper). Then last year, colleagues and I participated in a workshop in Nottingham, in which we modeled galaxy cluster catalogs that were then analyzed by different methods for estimating masses, richnesses and membership in these clusters. (See this paper for details.)

This time, we had an ambitious three week workshop in which each week’s program is sort of related to the other weeks. During the first week, we compared codes of different hydrodynamical simulations, including the code used by the popular Illustris simulation, while focusing on simulated galaxy clusters. In week #2, we compared a variety of models of galaxy formation as well as models of the spatial distributions and dynamics of dark matter haloes. Then in week #3, we’re continuing the work from that Nottingham workshop I mentioned above. (All of these topics are also related to those of the conference in Xi’an that I attended a couple months ago, and a couple other attendees were here as well.)

The motivation of these workshops and comparison workshops is to compare popular models, simulations, and observational methods in order to better understand our points of agreement and disagreement and to investigate our systematic uncertainties and assumptions that are often ignored or not taken sufficiently seriously. (This is also relevant to my posts on scientific consensus and so-called paradigm shifts.)

Last week, I would say that we had surprisingly strong disagreement and interesting debates about dark matter halo masses, which are the primary drivers of environmental effects on galaxies; about the treatment of tidally stripped substructures and ‘orphan’ satellite galaxies in models; and various assumptions about ‘merger trees’ (see also this previous workshop.) These debates highlight the importance of such comparisons: they’re very useful for the scientific community and for science in general. I’ve found that the scatter among different models and methods often turns out to be far larger than assumed, with important implications. For example, before we can learn about how a galaxy’s environment affects its evolution, we need to figure out how to properly characterize its environment, but it turns out that this is difficult to do precisely. Before we can learn about the physical mechanisms involved in galaxy formation, we need to better understand how accurate our models’ assumptions might be, especially assumptions about how galaxy formation processes are associated with evolving dark matter haloes. Considering the many systematic uncertainties involved, it seems that these models can’t be used reliably for “precision cosmology” either.

Will Climate Change Embolden the Environmental Justice Movement?

[I’m cross-posting this, which was originally posted on the Union of Concerned Scientists blog. Thanks to Melissa Varga for editing assistance.]

We are at an historic anniversary: the Civil Rights Act was enacted fifty years ago on the 2nd of July, 1964. According to the legislation, all persons “shall be entitled to the full and equal enjoyment of…any place of public accommodation, as defined in this section, without discrimination” based on race, color, religion, or national origin. It ended unequal application of voter registration requirements and racial segregation in schools, at the workplace and by facilities that served the general public. (Another milestone, Brown v. Board of Education, occurred sixty years ago.) The Civil Rights Act was initially about the important symbolism of inclusion. But what does this have to do with climate change?


We still need to address what sociologists refer to as institutionalized inequality and injustice. Randall Kennedy in Harper’s magazine asks, why has the struggle against racism been more effective in public accommodations than in schooling, housing, employment, and the administration of criminal justice? “What is the value,” the civil rights activist Bayard Rustin once asked, “of winning access to public accommodations for those who lack money to use them?” To address structural injustices and inequities, more action is required.

“Environmental justice” is meant to address a critical area where such injustices remain. Attorney General Eric Holder said in a speech at the Environmental Protection Agency in 2011 that Dr. Martin Luther King Jr. “plant[ed] the seeds of the environmental justice movement” and that environmental justice is “a civil rights issue.” The EPA defines environmental justice (EJ) as the “fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies.” EJ often refers to water and air pollution, soil contamination, toxic hazards, power plants, industrial facilities, and environmental degradation that preferentially affect residential areas and communities with people of a particular race, ethnicity, or economic status. It also refers to social movements that have, with some success, attempted to rectify this.

EJ is also particularly relevant to climate change. Issues of “equity, justice, and fairness” were referred to in the latest IPCC report, and as argued by Union of Concerned Scientists Senior Climate Economist Rachel Cleetus in an earlier post, EJ should be considered as a major factor in President Obama’s Climate Action Plan. We are already seeing extreme climate events, including heat waves, floods, wildfires, and droughts, and poor coastal communities are particularly vulnerable to storm surges, coastal flooding, and rising sea levels. Although dangerous weather events appear to occur randomly, some people are more vulnerable than others and some receive more effective aid during cleanup and recovery. (See the book “Race, Place, and Environmental Justice after Hurricane Katrina”, edited by Robert Bullard and Beverly Wright.) Sometimes environmental laws are insufficient and federal agencies don’t take sufficient steps to protect workers and residents, and certainly there is room for improvement.

A few weeks ago, I attended a meeting on Climate Change Resilience and Governance in Washington, DC, which was organized by the American Association for the Advancement of Science (AAAS). The speakers included Jalonne White-Newsome, a former UCS Kendall Science Fellow now a policy analyst for WE ACT for Environmental Justice. She talked about how currently EJ communities are not engaged in the process, and the failure to mobilize the majority of Americans who want action on climate change is partly due to the fact that not everyone is part of the conversation. Many black, Latino, and Native American communities, as well as working class white communities, live closer to various polluting industries, landfills, fracking infrastructure, etc. than others, but they don’t have enough information about what they can do about it, how they can communicate with the authorities, or how to receive the aid they need. (For more on this meeting, see my blog post on it).

Scientists, activists, and policy analysts are now thinking about and addressing the causes and effects of climate change. Although we want to substantially reduce carbon dioxide emissions and avoid the worst of global warming, climate change is already happening. Throughout different regions of the US, we can expect more frequent and extreme droughts, floods, and heatwaves in the future (see the overview of the National Climate Assessment.

This is where climate adaptation and resilience come in, and this is what people are actively working on these days. For example, people on the top floors of poorly cooled buildings in dense urban areas are among the most vulnerable to heat waves, and simple solutions like white-painted roofs (see below) can save many lives. Scientists and medical experts are also studying the cumulative impact to the health of vulnerable populations, for example following natural disasters (such as hurricanes or floods) that also damage the social and physical infrastructure necessary for resilience and emergency response. Afterward, federal agencies need to be ready to help local organizations and communities with reconstruction. To address future water shortages and drought impacts, Congress authorized the National Integrated Drought Information System in 2006, which identifies drought-sensitive regions and manages drought-related risks and which involves the coordination of federal, state, local, regional, and tribal partners.


There is certainly plenty more work to do on climate mitigation and adaptation, and environmental justice should be a key element of it. As we look back on all we’ve accomplished since the Civil Rights Act was passed fifty years ago, let’s keep working to eliminate injustice and inequality as we prepare for the great challenge of the 21st century—climate change.