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!

04/16/14

Beautiful, old things

by Meghan Beamish

From my 81 year old Grandma to rugged old juniper trees, those who have been living for a long time can teach us a lot. Examining the past is critical for understanding our current climate and making projections for the future. Rachel Saussman has been traveling the world to photograph some of the world’s oldest living things. Take a minute (or 2:57, to be exact) and enjoy the beautiful, old things in life.

04/10/14

Context-based climate learning

by Meghan Beamish

One of the central tenets of effective climate change communication (actually, any form of communication) is to know your audience. This tenet is centred around the fact that we all have a background that influences who we are and what we choose to believe. Our communities, families, religions, experiences, jobs all play a decisive role in determining how we react to and digest information that is presented to us. We all have a context.

But, if new information does not align with our established contexts, problems arise. Sometimes the information, no matter how scientifically true, is discarded. This is when facts are not enough.

In a recent Perspective in  Nature Climate Change, Elizabeth M. Walsh and Blakely K. Tsurusaki make a case for context-based climate education. I suggest going through and reading the whole thing, especially if you are interested in climate change education (and, even if you aren’t, the ideas and concepts that they present are applicable to wider science communication). It is a well crafted and engaging read. But I’ll paint a bit of a picture for you.

The way that I understand it, context-based climate education uses students’ backgrounds and initial understandings of climate systems as a starting point, and then works from there. Students and teachers explore why conflicting perceptions of climate change exist, while they integrate the scientific facts into lessons. This is an approach that requires deep engagement on both sides of the student-teacher relationship, but it doesn’t seem to require anything too radical:

Something as simple as having a discussion or giving a short survey can reveal not only students’ initial conceptual understandings, but also the interests, values, attitudes and relevant home and community practices that can be leveraged in a classroom to support holistic climate change learning.

Some advice for educators:

Rather than seeing controversies as something to be feared or relegated to a non-science class, we should instead view this as an opportunity to foster deeper science learning and to engage students in exciting, cutting-edge science.

I’ve seen this melding of  the science and social controversy in university level courses – here at UBC in Simon’s Climate Change: Science and Society, and in this recent New York Times article. If you ask me, these courses should be a graduation requirement for all, and the idea of combining scientific and critical-social thinking in high-school classrooms is a challenging but inspiring idea.

While the Walsh and Tsurusaki article focuses primarily on classroom education, the authors also make it clear that by engaging a person’s context into the climate discussion, we can foster deeper understandings of climate systems and the social controversy that exists around anthropogenic climate change.

So my advice to us all: let’s think about context. Start by thinking about your audience’s context. Maybe even take a survey. Then, encourage your audience to think about their own context.

04/8/14

The Vancouver Accord – An International Climate Change Agreement

by Simon Donner

Today, my class completed the “20th” Conference of the Parties to the UN Framework Convention on Climate Change. Groups of students representing 25 different countries worked feverishly to complete an agreement, submitting the final text with only a minute to spare.

The final product features many creative and detailed solutions to ongoing international climate policy disputes. Perhaps students should replace the delegates to the upcoming COP in Lima this fall!

Without further ado, here is the text of the Vancouver Accord, without the many bilateral side agreements:

OUTCOME OF THE MOCK 20th CONFERENCE OF THE PARTIES TO THE UN FRAMEWORK CONVENTION ON CLIMATE CHANGE

1. The parties of this convention agree with the findings of the Fifth Assessment of the Intergovernmental Panel on Climate Change that climate change represents a serious threat to the ecological and economic future of the planet.

2. A central goal of long-term collective action is the stabilization of greenhouse gas concentrations in the atmosphere at level that will keep global surface warming at minimum of 2°C above the pre-industrial average, contingent on the developed world providing financial and technical support to the developing world. Continue reading

04/7/14

A cooling conundrum: Surviving the heat waves of the future

by Meghan Beamish

If you’ve seen the new IPCC Working Group II report, you’ve probably seen this pretty graphic:

It shows  the observed impacts which published research studies have attributed to climate change in each of seven main regions (and sub regions) of the world. In addition to the observed impacts, the IPCC also published a table of the risks to human and natural systems (Figure SPM.1 if you are following along in the Summary for Policymakers). Risks result from the interaction of climate-related hazards with vulnerability and exposure (of both human and natural systems). Because I live in North America, I honed in on the greatest risks for my continent: wildfire-induced damage, flooding, and heat-related human mortality.

I grew up in Albuquerque, New Mexico, where summer temperatures push 30-40 °C. So that “heat-related human mortality” risk stood out to me. Here are the adaptation issues and prospects that the IPCC outlines for heat-related human mortality:

Residential air conditions (A/C) can effectively reduce risk. However, availability and usage of A/C is highly variable and is subject to complete loss during power failures. Vulnerable populations include athletes and outdoor workers for whom A/C is not available

Community- and household-scale adaptations have the potential to reduce exposure to heat extremes via family support, early heat warming systems, cooling centers, greening, and high-albedo surfaces.

Arguably, arid, hot cities in the Desert Southwest may already be the best adapted to this heat risk. Well, sort of.

Air conditioning is already a way of life in the Southwest. Most homes have some form of air conditioning; when I first moved to Vancouver, it had – embarrassingly – never really occurred to me that they sold – scratch that, made - cars and had apartments without air conditioning. The easy and logical response to those record-high summer days is to crank the A/C. But, while these cool houses in New Mexico reduce the risk of heat-related mortality, relying on current cooling mechanisms is not the best way to adapt to rising temperatures.

Many homes in the Southwest US, where it’s hot and dry, use evaporative cooling systems, what we call swamp coolers. Swamp coolers are fairly inexpensive to operate, and are low-energy users. They will only cool the air within a restricted range, so, when it gets really hot out, they will only reduce the indoor temperature by a certain amount rather than down to the desired temperature set on a thermostat (this also obviously depends on many other factors as well, like insulation).

Swamp coolers don’t work well when it gets humid during our brief “monsoon” season in the late summer. In addition to this, they use a lot of water – anywhere from 3.5-10.5 gallons per hour depending on the valve type. Taking into account that, according to NOAA, the entire state of New Mexico is currently in a moderate to extreme drought, swamp coolers are not ideal.

NOAA Drought Monitor

 

The other popular cooling mechanism (and the type that is used in most of the rest of the country) is refrigerated air. The upside of refrigerated air units is that that they don’t use any water and they can cool larger spaces to a more precise temperature range. The downside is that they are expensive and use about three times as much energy as swamp coolers. With the majority of New Mexico’s energy still coming from coal power, using refrigerated air as an adaptation is in direct opposition to the mitigation of climate change.

The IPCC suggests that household cooling and cooling centres are potential adaptations to heat-related mortality risks. There is a significant irony in that suggestion. By turning up the A/C on those record-high summer days, we enter a nasty positive-feedback loop. This cooling conundrum isn’t a new issue: check out Stan Cox’s Cooling a Warming Planet: A Global Air Conditioning Surge from Yale Environment 360 back in 2012. Promoting alternative ways to keep houses cool, such as through building practices and alternative cooling mechanisms – with, of course, alternative energy sources -  is necessary to reduce the risk of heat-related mortalities without contributing to climate change.

03/31/14

The IPCC and finding the balance between science and advocacy

by Simon Donner

Media coverage of the latest Intergovermental Panel on Climate Change (IPCC) report has followed the usual Goldilocks and the Three Bears pattern. The report, which focuses on impacts, adaptation and vulnerability, is either too soft (too conservative), too hard (overstating impacts, veering into advocacy) or just right.

Which is it? One problem is that every scientist or journalist you ask will have a different answer on the “right” IPCC message and the right next steps for the world. The answer depends a bit on the values of the person making the judgement. If the answer comes from a scientist – a profession with respect in society – the judgement will be seen as objective. Scientists, however, are also human beings! So, like the rest of humanity, our judgements can be influenced by our values.

The question of how scientists can choose their place on this continuum between science and advocacy is the subject of my new essay in Climatic Change.  The concept is straight-forward:

Scientists may be best served viewing science and advocacy as different ends of an approximate continuum. On the science-dominant end, judgements are more objective in nature. As scientists proceed towards the advocacy side of the continuum, personal worldview tends to have a greater influence on those judgements. The scientific uncertainty embedded in those judgements tends to increase, as scientists must draw upon additional models or decision-making processes each of which contain some uncertainty. The professional risk of judgements also increases along the continuum due to the cultural norms of science and the public perception of science as objective.

From there, I write about how scientists can be “scientific” about public engagement — make choices based on the available research on communications, advocacy, perception of scientists, and leakage of “normative” judgements into scientific decisions. My hope is that scientists will think carefully about their personal comfort level, whom they represent (in their eyes, and in the audience’s eyes), and the effectiveness of their chosen position:

The only “wrong” position on the continuum is one assigned by others or chosen without careful reflection.

What about the IPCC? Despite what you may read, the IPCC panels themselves are extremely thoughtful about providing an objective reading of the findings, often spending hours, even days, debating about how individual words will be perceived. This is reflected in the careful language the latest IPCC report uses surrounding the definition of “dangerous” climate change:

Human influence on the climate system is clear. Yet determining whether such influence constitutes “dangerous anthropogenic interference” in the words of Article 2 of the UNFCCC involves both risk assessment and value judgments.

Conservative? Alarmist? You be the judge. That’s the whole point.

03/25/14

Quote of the Week: Time Magazine on climate change, in 1956

“Since the start of the industrial revolution, mankind has been burning fossil fuel (coal, oil, etc.) and adding its carbon to the atmosphere as carbon dioxide. In 50 years or so this process, says Director Roger Revelle of the Scripps Institution of Oceanography, may have a violent effect on the earth’s climate…

Dr. Revelle has not reached the stage of warning against this catastrophe, but he and other geophysicists intend to keep watching and recording. During the International Geophysical Year (1957-58), teams of scientists will take inventory of the earth’s CO2 and observe how it shifts between air and sea. They will try to find out whether the CO2 blanket has been growing thicker, and what the effect has been. When all their data have been studied, they may be able to predict whether man’s factory chimneys and auto exhausts will eventually cause salt water to flow in the streets of New York and London.”

- “One Big Greenhouse“, Time Magazine, May 28, 1956

As part of the International Geophysical year, Revelle’s post-doctoral associate David Keeling established the CO2 monitoring station atop Mauna Loa in Hawaii (photos taken by an embarrassingly excited S. Donner). The now famous Keeling Curve is the longest continuous record of atmospheric CO2 measurements.

Funding for the regular measurements at Mauna Loa has long been an issue. You can now donate directly through a crowd-sourcing program to maintain this incredible record of planetary change.

03/23/14

The full range of future sea level rise, and what it means

High tide in Caqelai, Fiji reaches an old table (S. Donner)

by Simon Donner

We have been thinking a lot here about sea level rise, from the effect on tides to the UNESCO heritage sites at risk. If you search the media for the most recent IPCC sea level rise predictions, you’ll read that the 2013 report concluded that sea level was “likely” to increase by 45-82 cm by the “end of the century”. These numbers are misleading for two reasons, as was explained very well in a December letter to Science magazine by the very authors of the IPCC sea level rise chapter. The nuances may be important when making adaptation decisions.

First, what people present as “end of century” from the IPCC is, technically, an average of model-projected values for the year 2081 through the year 2100. Since sea level is expected to be rising rapidly at the end of the century – 8-16 mm/year, up to five times today’s rate – the difference between an average for those last twenty years and the value for actual end of the century is meaningful. The “likely” range for 2100 is actually 52 – 98 cm, not 45-82 cm. Continue reading

03/19/14

What do you get when you cross Art History and climate change?

by Meghan Beamish

People often stop and give me a funny look when I tell them that I am working on a double major in Art History and Geography. After that look, they invariably ask how these two fields relate to each other. To the surprise of many, they can actually complement each other quite nicely at times. Although, I will admit, when it comes to climate change and art history, the overlap is a little more rare. Which is why I get very excited when I come across papers that combine the two topics. Add a little GIS analysis in there and I am thoroughly hooked.

So, what do get when you cross Art History and global climate change?

The caves at Elephanta are at risk to sea-level rise.
(image courtesy of UNESCO, taken by Francesco Bandarin)

Continue reading