07/23/14

The NHL may be on thin ice, due to climate change

A new sustainability report from the NHL warns that climate change affects “opportunities for hockey players of all ages to learn and play the game outdoors”.

The report on sustainability initiatives may look like a bit of greenwashing from a sports league whose business can involve air-conditioning large stadiums to refrigerator levels in southern U.S. cities during June in order to play a winter activity. Nevertheless, the effect of climate change on outdoor ice, and the culture of Canadians and northern Americans is a real concern.

Liberty02The “ice season” on lakes and rivers all across the Northern Hemisphere has been shrinking. One of the longest records is from Lake Mendota, in Madison, Wisconsin, where I went to graduate school. The lake may be most famous for this Planet of the Apes stunt, first done by students back in 1979.

Welcome to the newest sequel, Melting of the Planet of the Apes.

The Mendota ice season averaged 122 days long back when observations began in the 1800s (1885-1875 average). Thanks to climate warming, the ice season is now more than a full month shorter! The average winter over the past twenty years featured only 85 days of ice.

mendota-durThis coarse metric of ice duration only tells part of the story. A lake that once froze in its entirety may now have portions that remain unfrozen all winter. During the record short 2001-2 ice season, enough of Mendota and other neighbouring lakes remained unfrozen that I considered taking my kayak out in mid-February, just for the sheer novelty of paddling in the middle of a Wisconsin winter.

A 2012 study in Environmental Research Letters suggested the shrinking ice trend extends even to artificial outdoor skating rinks. Using rink officials’ rules for deciding when the weather is safe enough to start the ice, scientists calculated that the skating season had shrunk over the past fifty years across Canada.

If the world continues on this greenhouse gas emissions trajectory, learning to skate on an outdoor rink may become a thing of past, as will a number of key economic activities, like traveling safely by vehicle across the roadless, lake-dotted landscape of northern Canada. In a few more decades, when we’re on to the thirtieth Planet of the Apes sequel, the UW students may have to haul Miss Liberty out on pontoons.

The NHL is smart be concerned about climate change. A favourable climate is foremost among the reasons that hockey – and watching hockey – is so fundamental to Canadians, and also Minnesotans and Wisconsinites. As the climate changes, culture may too, as we warn in this video. Kids are may be less likely to get interested in skating and ice sports… or parents may be less likely to drag their crying kids to the indoor rink to practice.  Next thing you know, they may be playing and watching other sports.

07/21/14

Is El Niño on the way?

Following on a study by my former student Sandra Banholzer and I about the influence of different types of El Niño on global temperatures, I sat down with UBC Public Affairs to answer some questions about the possible return of El Niño this winter.

When should we start to see El Niño develop and how will the average person notice it?

El Niño typically develops during our fall and reaches peak strength during our winter and early spring. Scientists are watching conditions in the Pacific Ocean to check early suspicions that a new figure4event is on the way.

El Niño itself begins far away in the equatorial Pacific. A reversal of winds and currents brings unusually warm waters to an area between the coast of South America and the International Date Line. This is like dropping a huge rock in a stream. The warm waters release so much energy into the atmosphere that the normal flow of air is diverted, affecting weather all over the planet.

If a strong event develops, people across Western and Central Canada should see an unusually mild, dry winter and spring. On the other hand, people across parts of the southern U.S. should see unusually wet conditions. 

Will climate change play a role in strengthening this El Niño?

Climate change affects everything that happens in the atmosphere and the ocean. The jury is still out on exactly how climate change affects the development of El Niño events.

One thing is certain: as the planet has warmed, El Niño events have also warmed. Our research shows that, all else being equal, an El Niño event today is warmer around the world than an identical event 100 years ago.

How could El Niño affect global agriculture and fishing?

El Niño is no joke. Regional heat and drought brought by a classic “Eastern Pacific” El Niño can be devastating to farmers in southern Africa, India, Southeast Asia, Australia, the Pacific Islands, and even the Canadian prairies. The warm El Niño waters also choke off the supply of nutrients to the great fisheries off the coast of South America. We’d all see the effect in global food prices.

One silver lining may be California. El Niño rains could offer a respite from the intense three-year drought that has crippled production in the Central Valley.

Will a potential El Niño affect global temperatures in the coming months?

In general, El Niño events are expected to cause a spike in global average temperature. But not all El Niño events are created equal. Research led by my former student Sandra Banholzer shows that only the classic events with the ocean warming in the eastern Pacific–as last happened in 1997/1998–definitely lead to an increase in global average temperature.

Since then, El Niño events have been more of the “Central Pacific” variety, which are not necessarily warm globally. The supposed “pause” in global warming over the past 15 years is nothing of the sort. The planet has been warming, but thanks to these naturally variable conditions in the Pacific, more heat than usual has gone into the ocean.

The overall global warming trend is so strong that even a weaker El Niño is enough to break global temperature records. This past May was already the warmest May in recorded history. If the overall Pacific  pattern flips in the coming months, bringing a strong classic El Niño, we’re likely to shatter global temperature records.

06/12/14

Finding the balance between science and values in public engagement about climate change

Researchers in the public eye have always struggled to find a balance between representing their results and being effective communicators. This was the subject of my recent essay in Climatic Change.875735-130928-kudelka

One solution, proposed by Roger Pielke Jr., is to be an “Honest Broker of Policy Alternatives” who provides all the available information and options. Thus, rather than pre-selecting policy options to present, which inevitably involves some value judgements, the honest broker presents all the options and allows the decision-makers to reduce the scope of options.

It is a very reasonable solution to avoid having the researcher’s personal values influence their public statements.  From my article:

Failure to consider the possible influence of normative judgements on one’s thinking can lead to “covert” or “stealth” issue advocacy, in which scientists do not perceive the implied advocacy position in their research or public statements (Lackey 2007; Pielke 2007). This can undermine one’s objective of informing the public and policymakers about science and policy options.

Yet many science communicators question whether it is possible to be an honest broker, since the process of filtering and synthesizing research for public consumption involves value judgements. This is especially the case if the data or knowledge is incomplete; the researcher must make a judgement on what information to include.

A recent Twitter exchange with Pielke about his USA Today op-ed piece about hurricane trends and storm protection demonstrated just how hard it can be to control for all personal judgements*.

My suggestion the op-ed was misleading led to some back and forth about the research methods and wound to a close with an honest, funny tweet from Pielke: “Guilty — Most aspects of hurricane mitigation/preparation did not appear in my 700-word op-ed”

The tweet rightly pointed out the absurdity of my complaining about what is and is not included in a short op-ed. How could anyone fully explain the difficulty of estimating for the influence of storm preparation on the costs of storm damage, let alone all of the other research studies on the subject, in 700 words? Especially if you want those 700 words to be interesting enough to be accepted by a major newspaper?

Inclimate-change-science-v-politics-cartoon presenting the findings to the public, subjective judgements had to made about which findings warrant mention. Yet this is what someone playing the honest broker would seek to avoid. A partial solution to this dilemma, suggested years ago by Stephen Schneider and discussed in my article, is to make backup materials available. Today, a blog is an easy, accessible way to present the detailed evidence behind a position taken in a shorter public statement. Many of us, including Pielke, maintain blogs for that reason.

The problem is that we are still making choices in preparing that backup material. And, regardless, few people will ever read the material. We’re lucky if they read the whole op-ed, rather than just the headline! One outcome of this is that even if a researcher perceives herself or himself to be close to the honest broker ideal, others may not.

It is for these reasons that I encourage students to understand their motivations and personal biases, rather than strive to be objective automatons. We can’t remove all personal judgements. But we can strive to be honest with ourselves about our values and motivations and take them into account when engaging with the public. From my essay:

Finding a comfortable and effective position on the science-advocacy continuum requires analyzing ourselves with the same rigour we would use to analyze our data.We are scientists, but we are also citizens, voters, taxpayers, parents, children and homeowners. Research on science communication suggests that we must consider our knowledge, our motivation, our cultural values and our ability to reach different audiences in order to be effective at public engagement… This self-analysis is critical to making personal biases explicit and separate from scientific findings, to recognizing the limits of your communication abilities, and to protecting the hard-won public trust in science.

06/6/14

Global warming or Climate Change? It depends when and where

For years, people have argued over the best term to describe what is happening to the climate: global warming or climate change.

Market-savvy environmental groups have tried re-branding the issue entirely, producing terms like global heating, global weirding, global melting, climate crisis, climate disruption, climate chaos, springtime for CO2, climate farklempt, I’ve got some coastline in Florida to sell, etc. etc. The two originals, global warming and climate change, continue to corner the market like the Coke and Pepsi of the climate world.

A recent study by the Yale Project on Climate Change Communication found that global warming is more “effective” from a communications standpoint than climate change. Detailed public opinion analysis showed that “global warming” instills more concern about the issue and generates more motivation to take action.

The study also points out that the American public has for years used global warming far more than climate change, at least according to Google search data. However, if you dig further into the search data, you find some changing patterns.

Here is the U.S. search volume going back to 2004:

US search volume2Global warming certainly dominated the “aughts”. Since then, its relative use has declined. If we look at the ratio of searches for global warming and climate change in the above data, you see that word preferences have been changing:

US vs. Canada ratio in searchesIn the US (blue), the ratio has declined towards the 1:1 line (black), meaning that today there is close to an equal proportion of searches for global warming and climate change. That’s a big change since the mid-2000s, when global warming vs. climate change was like the Harlem Globetrotters vs. the Washington Generals.

In Canada, global warming was never nearly as dominant term north of the border. Climate change is now searched more often (52% of combined searches in 2014). This is no surprise to Canadians; the term climate change was adopted here years ago by most political parties and the media. That decision probably reflects the more moderate Canadian political climate, where people are more likely to trust authority, in this case, scientists and their preferred term. Granted, it also may reflect the actual climate; the term “global warming” may be scary if you live in Phoenix, but dreamy if you live in Winnipeg.

Narrowing the U.S. search data by region shows a huge geographic divide in the preferred term and the interest in the subject. For example, the next graph compares the search ratio for Texas and for the Bay Area. I tried using individual metropolitan areas in Texas and other conservative states, like Dallas-Ft. Worth or Houston, but none featured consistently high enough search volume for the past ten years. As it is, the Texas data had large gaps before 2007 (and one in 2008), when search volume was too low for the Google metric.

Texas vs. Bay Area ratio in searchesThe ratio is dropping in both Texas and the Bay Area. Texans, however, still prefer global warming by 2:1 or more over climate change. People in the Bay Area, however, are almost evenly split (52% global warming in 2014).

If you examine the overall data state by state, a clear pattern emerges. Republican-leaning states in the southeast and central U.S. have the highest global warming to climate change search ratio, whereas Democratic-leaning states have the lowest ratio. Texas is actually not even among the top ten in global warming preference. tableWashington DC is the only “state” where climate change is the preferred term, no doubt related at least in part to its use in government.

Harry Enten at fivethirtyeight came to a somewhat similar conclusion using data from U.S. Congress and cable news channels. Enten found that democrats prefer “climate change” and Republicans prefer “global warming”. He then argues that the Yale research would recommend the exact opposite:

If the polling is to be believed, Democrats, Republicans and the news channels they watch are actually having the opposite effect they are intending. We’ll have to see whether the Yale study makes them reverse course.

There are many unresolved questions, including whether the influence noted in the Yale Study is changing over time, and what that means for language choices. Does the choice of wording matter among people who are already motivated, like many in the Bay Area, or those whose attitudes are unlikely to change?  And would re-labeling by either party be so obvious to the public as to undermine the objective?

Regardless of the answers, one thing is clear from the search data. We are not paying nearly enough attention to ocean acidification:acidification search

05/26/14

Coral-eating starfish: An outbreak of Crown-of-Thorns Starfish in Kiribati


Last year, people in Butaritari Atoll, at the northern end of Kiribati’s Gilberts Islands began noticing these large spiny starfish depicted in the video above and photo below. The exotic-looking “crown-of-thorns” starfish, known as Acanthaster planci to scientists and latin-speakers in Brooklyn, is famous for preying on reef-building corals. Outbreaks of crown-of-thorns starfish can lead to drops in the amount of living coral on reefs, as has happened in places as varied as the Middle East and the Great Barrier Reef.

COTs off Betio, Tarawa

Crown of Thorns Starfish off Betio, Tarawa (S. Donner)

The Kiribati outbreak spread south to the central atolls of Abaiang and Tarawa over the past year. I filmed the shaky video above while conducting a coral reef survey in a, hmm, fast-flowing channel between the open ocean and the Abaiang lagoon (the word ‘drift’ is too passive to describe this dive; it was more of a ‘raging river’, ‘don’t hit anything’ or ‘I hope the boat can find us’ dive).

In the video, you can see the crown-of-thorns damage looks a lot like coral bleaching. One key difference is the spatial pattern. With a crown-of-thorns outbreak, as in the video, you often see isolated patches of whitened corals or large white circles on otherwise healthy looking mound or table corals.

We’re not absolutely sure what initiated this particular outbreak or any other outbreak for that matter. Marine scientists generally suspect that over-exploitation of the few predators of the crown-of-thorns, like triton or ‘conch’ shells, is the most likely cause of such outbreaks. It is also possible that nutrient pollution can indirectly promote the spread of the starfish through increased survival of their larvae. I hope that, if funding allows, we can at least track the long-term effect of the outbreak on the coral reefs of the island chain.

05/22/14

Look up! Bull sharks and coral bleaching

OReason #1 not to focus too heavily on studying bleached corals (lower left).

In order to collect data on the “benthic” or bottom cover of a reef, you must spend the majority of the dive swimming < 1-2 metres above the bottom and looking down. My Kiribati dive colleagues and I like to joke about what swims by when we’re not paying attention. On one dive during this recent trip, I watched a small reef shark swim wide circles – harmlessly, I should add – around my dive buddy Toaea, who was focused on taking bottom photos. On a subsequent dive, Toaea watched a barracuda – also harmless – float above oblivious me as I measured some tiny corals buried in the reef.

The photo of this bull shark was actually taken on a recreational dive in Fiji — so, at least this time, everyone saw the shark. I took advantage of the necessary layover on the way to Kiribati to test some gear and investigate a minor bleaching event. Water temperatures were elevated more than usual around most of the Fiji islands during the Southern Hemisphere summer. The temperature spike was enough to trigger bleaching warnings from the NOAA Coral Reef Watch system. A lot of corals, like the small Acropora in this photo, remained bleached in April.

 

 

05/21/14

Coastal rock art? Dispatch from Kiribati

This is part of a series of posts featuring stories, photos and video from a recent field research trip to Kiribati.

What explains the amazing rock formations on coasts of Kiribati?

Fluke coral growth? Ancient rock art like the Nazca Lines? Photoshop?

O

They are te ma – traditional fish traps – built from Opieces of rock or coral collected along the shoreline.

When the tide is in, fish can swim along the “shaft” or through a direct entrance into the heart- or arrowhead-shaped openings.

When the tide recedes again, fish get trapped there and are easy prey. The shaft also helps point people to the place to collect the fish.

These traps can be found at Temaiku, the SE tip of Tarawa, just south of the airstrip.

 

 

 

04/20/14

The rate of change

by Meghan Beamish

While reading through the latest IPCC reports – Working Groups II and III – one word kept popping out at me: rate. Specifically when I compared this phrase:

The overall risks of climate change impacts can be reduced by limiting the rate and
magnitude of climate change.

To this:

About half of cumulative anthropogenic CO2 emissions between 1750 and 2010 have occurred in the last 40 years (high confidence).

With this summary of adaptation plans in North America (I added the emphasis):

In North America, governments are engaging in incremental adaptation assessment and planning, particularly at the municipal level. Some proactive adaptation is occurring to protect longer-term investments in energy and public infrastructure.

And this:

Within this century, magnitudes and rates of climate change associated with medium- to high-emission scenarios (RCP4.5, 6.0, and 8.5) pose high risk of abrupt and irreversible regional-scale change in the composition, structure, and function of terrestrial and freshwater ecosystems, including wetlands (medium confidence).

And finally:

Greater rates and magnitude of climate change increase the likelihood of exceeding adaptation limits (high confidence). Limits to adaptation occur when adaptive actions to avoid intolerable risks for an actor’s objectives or for the needs of a system are not possible or are not currently available. Value-based judgments of what constitutes an intolerable risk may differ. Limits to adaptation emerge from the interaction among climate change and biophysical and/or socioeconomic constraints.

So, I suppose my question is, do our rates of adaptation and mitigation match the rates of climate change?

04/17/14

Will the next El Nino break a global temperature record?

by Simon Donner

Cherry trees blossomed in Vancouver in early February during 2009-10 El Nino

Long-term forecasts say El Nino could be on the way.

This periodic climate warming of parts of the equatorial Pacific Ocean can affect weather around the world, often creating droughts and fires in Australia, Papua New Guinea and parts of Africa, heavy rains and flooding in California and parts of South America, and warmth across much of Canada and the northern U.S.

If you add it all together, forecasters often say El Nino years are unusually warm worldwide. The last strong El Nino event led to 1998 being the then-warmest year in recorded history.

Would the return of the mischievous brat of the climate system lead to a new global (surface) temperature record and an end to the “pause” in surface warming?

Not so fast. It could, yes. But not all El Nino events are created equal.

According to a recent study by my former student Sandra Banholzer and I, only “Eastern Pacific” El Nino events lead to global warmth. I’ll explain the difference.

Under normal or “neutral” conditions, winds blow from east to west across the equatorial Pacific. This causes the upwelling of cold water in the east that feeds the famous coastal fisheries of South America and the amazing marine life of the Galapagos.

Temperature anomalies, or departures from normal, with depth across the equatorial Pacific

Whenever these easterly winds slow down or stop, the warm water piling up in the western Pacific – and I mean literally piling up, as the ocean can be tens of centimetres higher – can slosh back eastwards. This slow, long, east-moving wave of warmth is called a Kelvin wave. For an example, the image at right depicts the current Kelvin wave using temperate “anomalies” across the Pacific.

In general, if the change in the winds is strong and persistent enough, the Kelvin wave or series of Kelvin waves will be really warm and powerful, enough to cut off the upwelling in the east and dramatically warm the Pacific all the way from the South American coast across the International Dateline. This is what happens in a classic “Eastern Pacific” (EP) El Nino, like 1997/98 or 1982/83 (despite all the excitement about images like the above, the current Kelvin wave is alone not enough to trigger such an event; there would need to be continued or further gaps in the easterly winds).

On the other hand, if the switch in the winds is short-lived or happens only in the western half of the Pacific, the surface warming will be restricted to the middle of the Pacific, around the International Dateline. Scientists have been calling these events “Central Pacific”(CP) El Nino or El Nino “Modoki”.

Full image from February 2005 storm in Tarawa

In fact, the header for this blog comes from a photo taken in Tarawa, Kiribati – right in the Central Pacific, 7 degrees west of the International Dateline – during the 2004/5 Central Pacific event. The elevated ocean temperatures caused bleaching of corals in Kiribati (pdf), and launched my field work. In the photo, you’re seeing a combination of high seas from the CP El Nino event, an El Nino driven westerly storm and a high tide blast the homes along the lagoon shoreline with waves.

The effects of an El Nino event on weather around the world (“teleconnections”) can depend on the type of event because of how the location and extent of abnormally warm Pacific waters affects the atmosphere. Our study showed that if you control for the other influences on global average surface temperature (like volcanoes and the human-induced trend), Central Pacific and “mixed” events are not unusually warm globally. Only the Eastern Pacific events affect the global average surface temperature.

This has important implications for the “pause” in surface warming. Over the past 10-15 years, the easterly winds have been abnormally strong, with few gaps sufficient to generate Kelvin waves. This is related to decade-scale variability in the Pacific Ocean conditions, called the Pacific Decadal Oscillation (PDO) or Interdecadal Pacific Oscillation (IPO).

It may then come as no surprise that all the El Nino events since 1998, including the 2009/10 event that made the cherries blossom early in Vancouver, have all been of the CP variety.  The same happens to be true for other “slowdowns” in the rate of global surface temperature change since the Industrial Revolution. This suggests the decade-scale variability in the Pacific affects El Nino development, and in turn, the ups and downs in the rate of human-caused global surface warming. From the conclusion of our paper:

The current mean state of the Pacific tends to restrict wind anomalies and anomalous convection to the central Pacific, and hence favours CP rather than EP events [Xiang et al., 2012]. A shift in the mean state of the Pacific back to a warm phase in a few years may allow for globally warm traditional EP El Niño events to return.

Could this coming El Nino spell the end of the pattern?

It is simply too early to say for certain. There are some telling signs. For one, the change in upper ocean heat content over the past three months is similar to that of the last two Eastern Pacific events (1997/98, 1982/83). We should be careful about reading too much into those numbers. There are other years in which such a pattern in upper ocean heat content did not lead to an Eastern Pacific El Nino event.

Unfortunately, patience is not a virtue on the internet!