Category: Sea level

Putting the genie back

dchone August 25, 2017

As I have posted in recent weeks, my complete book on climate change is now out, under the title ‘Putting the Genie Back: Solving the Climate and Energy Dilemma‘. The publisher, Emerald Publishing Limited, has just made the first chapter available on-line so that you can try before you buy.

Their advertising for the chapter included a quote from President Barack Obama, which gives a hint as to where the title came from, but isn’t the whole story. In May 2014 the President had invited several meteorologists to the White House for exclusive interviews on the climate change report that the administration released earlier in the week. The president summed up the importance of the situation with one simple phrase: “it’s hard to put a genie back in the bottle.” The quote was part of a longer piece which was referring to the climate itself and the possibility of reaching a tipping point. He had said;

“I want to make sure that my children and my grandchildren are able to enjoy a beautiful day like today; that they’re not living in a more dangerous world. […] This is one of those things that is very difficule to recover from. Once we hit a certain tipping point, we don’t know exactly how certain weather patterns could end up resulting in catastrophe. It’s hard to put a genie back in the bottle.”

By that time my first e-book, which the current book also incorporates, was in the late stages of writing and I had already pencilled in the genie metaphor, although with other suggestions coming from friends and family, I wasn’t entirely sure. My use was never in relation to the climate itself, but to the use of fossil fuels. That particular genie has ushered in astounding progress for society, but it is also a genie that is hard to challenge. Nevertheless, we can, with carbon capture and storage representing a method of returning the carbon to the subsurface, effectively putting the genie back.

Even though my intended meaning wasn’t the same as the President, when he also used the phrase in relation to climate change it seemed like the decision was made.

Enjoy the pre-read and I hope you buy the book. My proceeds are going to the Centre for Climate and Energy Solutions (C2ES) in Washington D.C.

Visualizing Change

dchone July 28, 2017

Climate change is one of those very difficult things to see first-hand, in that we need some form of historical reference and a clear link to warming. Further, the reference point needs to be visual and significant to have an impact. Sea level is one such reference, although in the clear majority of cases it moves so slowly that any reference to the past is almost impossible to discern. I lived in seaside areas on and off for several years in the 1970s and 1980s, but returning 30-40 years later offers little to no visual hint of change, even though change is underway.

I recently visited Chamonix in France where a very significant change is both underway and clearly visible. You can take the rack and pinion railway nearly a kilometre vertically from the town up to Montenvers, where the Mer de Glace glacier can be viewed and visited. This is the longest and largest glacier in France, and the second longest in the Alps. The scene from Montenvers, like much of the Alps, is beautiful, although the glacier itself is not easy to visualize in that its surface is largely covered with a dusting of debris from sides of the valley. Nevertheless, it is an imposing scene and more than worth the visit.

But this is just the beginning of the story. The glacier is shrinking rapidly, the first indication of which comes from the viewing sign that includes a dotted line showing the height of the glacier in 1820. The drop in height is very significant, but if that isn’t sufficient visualization of change, then a walk down a rocky path from Montenvers and then finally some 400+ steps to the glacier surface not only brings home the scale of change but also the rate – which appears to be accelerating.

The first impression comes when the hiker arrives at the 1820 line, well above the current glacier. This is quite a sobering moment in that there is no sign of ice, just summer wildflowers and trees.

This is just the first of many year signs, but the impression of acceleration comes lower down. Once the stairs are reached the first of several closely spaced signs appears, this one for 1990.

Soon after that comes 2003 (bottom right corner of the picture) and then finally the surface of the glacier itself, which brings the hiker to 2017. The drop from 1990-2003 was sizable for 13 years, but seemed small compared to the 2003-2017 change (14 years). The first drops from 1820 to 1920 and then 1985 seemed smaller by comparison.

The changes to the Mer de Glace have been widely recorded and written about, including an excellent report on the rate of decline based on Landsat satellite images. In its 5^th Assessment report the IPCC noted the general demise of mountain glaciers as follows;

Despite their variability due to different response times and local conditions, the annually measured glacier terminus fluctuations from about 500 glaciers worldwide reveal a largely homogeneous trend of retreat. In Figure 4.9 (see below for the Central Europe extract), a selection of the available long-term records of field measurements is shown for 14 out of the 19 RGI regions. Cumulative values of retreat for large, land-terminating valley glaciers typically reach a few kilometres over the 120-year period of observation. For mid-latitude mountain and valley glaciers, typical retreat rates are of the order of 5 to 20 m/year. Rates of up to 100 m/year (or even more) are seen to occur under special conditions, such as the complete loss of a tongue on a steep slope, or the disintegration of a very flat tongue.

Cumulative length change in metres vs. year

Recognizing that the reasons for change for any given glacier can be many and varied, the global trend is very clear and Mer de Glace is one example of this. If you are in the region over the summer vacation period then a visit is highly recommended, with the bonus of being able to walk inside the glacier when you finally reach the surface, thanks to some ingenious tunneling by the local tourist authorities.

Climate impact of energy system scenarios

dchone March 29, 2016

Shell has over 40 years’ experience in developing energy scenarios*, but the expertise to assess the physical climate impacts of these doesn’t exist within the company. While it is relatively easy to calculate the cumulative carbon emissions over the course of the 21^st century for a given scenario and then equate this to some level of climate warming, a more accurate and complete look at the physical impacts, including warming itself, of a certain energy pathway can only come from a comprehensive earth systems model.

For such an assessment, Shell has turned to the MIT Joint Program on the Science and Policy of Global Change. We first worked in this manner with MIT in 2008 when there was a mutual interest in looking more deeply at the previous set of Shell energy scenarios (Blueprints and Scramble) alongside a number of other scenario studies, releasing a paper on the work towards the end of that year. At the request of Shell, a new assessment has just been completed by MIT, this time looking at the New Lens Mountains and Oceans scenarios which were first published in 2013. The paper is now available on the Joint Program website. The analysis also included scenarios based on different pathways following COP21 and a reference MIT 2°C scenario which assumes the necessary globally uniform carbon tax to deliver such an outcome.

MIT used their Integrated Global Systems Model (framework shown below) to do the work in 2008, which has been repeated over 2015 for the current work. The model has evolved considerably since then, particularly in the areas of 3D analysis (e.g. 3D atmosphere), regional granularity, agriculture and land use.

MIT Global Systems Model

Energy system carbon dioxide emissions for the five scenarios in the analysis are shown below (NCP2020 represents a “no climate policy” pathway and Outlook reflects the COP21 INDCs but without the assumption that they are rigorously improved on over the years). Importantly, the Shell scenarios approach net-zero carbon dioxide emissions by the end of the century, effectively limiting the accumulation of this gas in the oceans-atmosphere system. The total cumulative anthropogenic emissions over time is strongly linked to the amount of climate system warming.

Scenario emission profiles

Both Shell scenarios see the progressive and widespread introduction of policies to manage emissions. In the Oceans scenario this appears as a market response triggered by government implemented carbon pricing that develops globally over time. Solar PV dominates in this scenario. In the Mountains scenario a more regulatory based approach is implemented, which sees the rapid emergence of carbon capture and storage (CCS) in particular. Both Shell scenarios result in a stabilization of CO2 in the atmosphere in the latter years of the century, although at levels higher than for the 2°C reference case. This means a 2100 temperature outlook +/- 2.4°C above pre-industrial levels for the Mountains scenario and +/- 2.7°C for the Oceans scenario.

MIT CO2 Concentration

MIT temperature outlook

The MIT report tackles a number of impact issues, including global precipitation, ocean acidity, sea level rise, water stress, air quality and agricultural yields. The sea level rise projections are based on thermal expansion of the oceans and melting of mountain glaciers, but not through major changes in the permanent ice shelves (Greenland and Antarctica) where there remains great uncertainty with regards the outlook.

The scenarios show that significant policy measures are needed to stabilize temperatures and climate impacts. MIT conclude that more stringent emission reduction scenarios (Oceans, Mountains, 2°C) are successful in mitigating a large portion of water stress impacts and air pollution damages. They also cap the ocean acidity increase, while agricultural yields are still strongly affected. The report notes that these projections show a significant value of policies that may not end up in 2°C stabilization but fall substantially close to that target by the end of the century.

* Shell Scenarios are part of an ongoing process used in Shell for 40 years to challenge executives on the future business environment. We base them on plausible assumptions and quantification, and they are designed to stretch management to consider even events that may be only remotely possible. Scenarios, therefore, are not intended to be predictions of likely future events or outcomes and investors should not rely on them when making an investment decision with regard to Royal Dutch Shell plc securities.

Is sea level rise entering the mainstream?

dchone August 23, 2013

Mid-August is never a great time for activity on the climate front, particularly not in holiday bound Europe. Perhaps the “highlight” of the week was the leak of a late draft of the upcoming Summary for Policymakers of the IPCC WG1 5th Assessment Report. The formal release is near the end of September, but the leak has caused quite a stir. Most mainstream media have reported on at least one aspect of the draft document, in almost all cases highlighting that the temperature rise seen over the last 100 years is “extremely likely” caused (at least more than half of it) by the release of CO2 into the atmosphere from the use of fossil fuels by humans. This is a more certain statement than has been made in the past by IPCC.

A few media outlets that felt that their audience perhaps knew this, ventured further and tended to focus on the sea level rise projections that the IPCC have put forward (at least in this leaked draft). IPCC note that it is “virtually certain” that the rate of global mean sea level rise has accelerated during the last two centuries. For example, ABC (Australia) reported that ”sea levels will rise by between 29 and 82cm by the end of the century, with scientists fairly confident that will be the upper limit.”

The draft Summary Report also picks up on an issue I posted on last week, that being the sensitivity of sea level to global temperature and therefore the very substantial rise that could occur over the coming millennia as a result of the temperature rise now under way. IPCC note that:

There is very high confidence that the maximum global mean sea level was at least 5 m higher than present and high confidence that it did not exceed 10 m above present during the last interglacial period (129,000 to 116,000 years ago), when the global mean surface temperature was, with medium confidence, not more than 2°C warmer than pre-industrial. This sea level is higher than reported in AR4 owing to more widespread and comprehensive paleoclimate reconstructions. During the last interglacial period, the Greenland ice sheet very likely contributed between 1.4 and 4.3 m sea level equivalent, implying with medium confidence a contribution from the Antarctic ice sheet to the global mean sea level.

National Geographic also picked up on sea level in their September issue, with a cover feature and a comprehensive set of charts, graphs and videos (for the iPad version) as only National Geographic can do.

Unfortunately the cover has already come in for criticism from one blog site in particular, arguing that NatGeo is scaremongering as it will take thousands of years for sea level to rise to that level (about 60 metres) on the Statue of Liberty. In fairness, the magazine does point this out in the article where it has a graphic showing what the coast would look like if all the ice sheets melted (i.e. both Antarctica and Greenland over several thousand years). There is no assertion by NatGeo that this will happen, it’s just a graphic to give readers some idea of the full scope of the sea level issue.

All of this raises the possibility that sea level rise may become the eventual poster-child for climate change. While floods, droughts, storms, heat waves and forest fires all have the “wrath of God” feel to them, they are unpredictable, uncertain and have always been with us. No single event can be attributed to anything other than a chaotic system and a complex statistical analysis over a long period of time is required to make the case that a change is underway. This makes it very difficult to use these events to gain public appreciation of the climate risk and therefore build any consensus around a suitable course of action. As is now also apparent, global surface temperature itself is not that reliable either and the alternative of trying to get mainstream understanding of a global heat imbalance (oceans, air , ice etc.) is probably just too difficult. But sea level just keeps rising!

All that being said, an observer of the NASA web site on climate indicators will note that sea level took a remarkable dip and recovery over the last two years. Apparently this is due to very heavy and widespread rain in Australia over that period. The continent acts like a basin and “traps” the water to some extent, at least for a while until evaporation and drainage eventually do their job. Extraordinary!