El Niño or Climate Change?

We might have just experienced one of the warmest Christmas in 50 years, accompanied by series of extreme global weather around the world, thanks to El Niño. From record-breaking temperatures over the Christmas holiday in the US (the New Yorkers were complaining that they didn’t get the White Christmas they used to have this year) and forest fires in Australia, to a lacking of snowfall in the Alps which made the skiing condition around the area less desirable, and some of the worst floods ever known in the UK. Study reveals a reciprocal relationship between El Niño effects and impacts of anthropogenic global warming - climate change is likely to intensify the effects and double the occurrences of El Niño in the future in response to global warming, which create more tumultuous weather events around the world that make the effects of climate change even worse. 

The natural phenomenon El Niño, also known as the El Niño Southern Oscillation (ENSO), is caused by warm ocean waters forming in the central and east-central Pacific, which then leads to a chain of climatic events that can cause significant changes to global weather patterns. During a moderate El Niño period (i.e. Modoki El Niño) (see Fig. 1), the eastern margin of the warm pool and the atmospheric convection zone migrate eastwards to just east of the Date Line, whereas the ITCZ locates north of the Equator, leading to a strong anomalous warming in the central tropical Pacific (fall in air and surface pressure) and cooling in the eastern and western tropical Pacific (rise in air and surface pressure). 

Fig.1 Anomalous SST during Modoki El Niño, 

Source: JAMSTEC

During an extreme El Niño (see Fig. 2), the warm pool expands eastward until it covers the entire eastern equatorial Pacific, weakening the equatorial east-west and meridional sea surface temperatures gradient. The oceanic convection then follows the highest SSTs and extends eastward while the ITCZ shifts equatorward, bringing atmospheric convection and anomalous rainfall patterns (> 5mm per day) in the normally dry eastern equatorial Pacific. As such, westerly winds dominate the easterlies and suppress the cool eastern equatorial upwelling (Anomalous El Niño, Nature), thus reinforcing the anomalous high SSTs in the region. 

Fig.2 Anomalous SST during extreme El Niño, 

Source: JAMSTEC

El Niño is certainly not a result of climate change but the latter has the impact to make its effect worse. Under anthropogenic global warming, the eastern equatorial Pacific experiences a faster warming rate and weaker zonal and meridional SST gradients than other parts of the world. Weaker changes in SST gradients assist shifts in convection zones more easily, thus increasing the chances of occurrence of extreme El Niño in the future (see Fig. 4).  

Fig. 3 Multi-model statistics associated with the increase in the frequency of extreme El Niño events.  Multi-model histograms of the meridional SST gradient in the eastern equatorial Pacific for all samples, and for extreme El Niño alone. Blue represents the moderate periods while red indicates climate change periods. 

Source: Wenju Cai et al. 

Fig. 4 Schematic depicting the mechanism for increased occurrences of extreme El Niño under greenhouse warming. Source: Wenju Cai et al. 

Extreme weathers are found more common around the world, mostly as a result of climate change, but also with the warmth reinforcement of the El Niño effect. If climate change is proved to have impact on increasing the occurrence and doubling the effect of El Niño, the world will certainly be expecting more extreme weather and stronger weather contrasts. 

Source: Inkcinct Cartoon

New climate adaptation measures like cooling measures, flood and drought defences, cyclones and typhoons defences should be constantly updated. According to Gail Whiteman, the chair of the Peatland centre for sustainability at Lancaster University, ‘[w]hat may appear to be sufficient to withstand a 1 i  100-year event can become quickly out of date as the incidence of extreme weather ramps up and becomes more unpredictable’. 

COP21 Cartoon

So we all know the countries have finally reach a consensus about environmental protection, for the first time in over 20 years of UN negotiations. But what does the agreement really mean?

The goal of keeping annual global warming below 2 degree celsius by regulating emissions may help to change a little, providing a temporary relief for the world's most endangered species. Yet, global warming is still occurring at a slower pace...

Source: Hill J., Cartoon: Paris Climate Change Agreement

Source: Adcock B., Climate Change Conspiracy

Source: Bjorland H., Environment Cartoon

In face of current terrorist attacks, would the politicians be keen on prioritising environment protection over national security? 

Source: Chappatte P., Chappatte on the Paris Climate

China Airpocalypse II: Effects on the economy

Apart from the climate and health impacts I have mentioned in my last post, air pollution also  hinders economic growth in China in three ways:

• The cost of air pollution and its negative externalities consumes large sum of national income, which limits government budget on other aspects such as education, public health, infrastructure which helps to increase productivity in the long-term. According to Zhang Gaoli, who is one of the ruling Communist Party’s elite Politburo Standing Committee, environmental degradation has been the cost of decades of breakneck economic growth China. The Chinese government has spent $10.5 billion on efforts to tackle the smog and environmental protection.

• Health is a form of human capital. Increased probability of getting respiratory or cardiovascular diseases triggered by aggravated air pollution reduces the quality and productivity of the country’s human capital. This should lead to a fall in average output per worker, and a slowdown in economic growth. According to Weil’s Growth accounting framework, the economic output Y (also known as the Cobb-Douglas aggregate production function) is expressed in terms of inputs K (capital) and H (labour composite).

1. 
   where A represents level of productivity of the economy, labour composite H depends on education, health and raw bodies. So it gives,
   
   
   where h is per-worker education human capital, v denotes per-worker health human capital, and L marks the number of workers in the economy.
   
   As such, fall in h should reduce labour composite H productivity and final output. This assumption takes health impacts caused by air pollution as the only variable, any health impacts related to chronicle diseases and government intervention on public health are irrelevant in this case. In addition to this, workers have to spend a greater portion of their income to deal with the costs related to air pollution i.e. medical treatments, masks consumption, air filters, etc. As such, workers have a smaller budget on consumption and their ability to increase living standard is reduced.

• The issue of aggravated air pollution has led to closure of schools in various cities, even though it just lasted for a day. In terms of economics, the event reduces students’ opportunity of getting education, and so impacting the quality of potential education human capital, despite it is a one-day closure and should not lead to any significant effect in future economy. But more importantly, the decision made by the city authorities proved that the air pollution problem has now becoming an issue that will affect our daily life routines, industrial production and market operations. This makes the problem difficult to ignore and that the government should take realistic action with a pro-active attitude to gradually reduce the level of hazardous air pollution. 

The causal factors of this hazardous particulate pollution are mainly the overly-expanded manufacturing sector in the economy which a majority of them uses fossil fuel (coal) as their energy source, and the country’s unreasonable modes of energy consumption. In light of China’s growth slowdown, an economic update released by the World Bank suggests an economic reform to a more moderate and balanced economy, by reducing excess capacity in industry and better indigenous capacity for innovation for instance.

The economy is gradually shifting from industry to servicing sector, despite the robust in the latter is relatively weak and immature in sustaining growth. Source: World Bank staff calculations based on CEIC data

Shifting the economy from smoke-stack industries to tertiary servicing is likely to stimulate economy recovery and reduce GHGs emissions. The economic reform are supported by the rise of middle-class, which has a higher preference for services, and a fall in industrial activity due to a buildup of excess capacity (over investment) and decelerating export growth (fall in import demand in the EU market). The reform, however, is a long-term economic solution in regards to the air pollution problem.

Source: World Bank staff calculations based on CEIC data

The government should also start investing in other renewable or cleaner energy sources instead of burning fossil fuels. From a bottom-up perspective, citizens should adapt a more sustainable use of energy. A simple cartoon below illustrates possible solutions to achieve energy-efficiency in our home. 

Source: BBC Bitesize

Here comes the time when the public needs are consistent with the government preference, in the case, air pollution is the most imminent issue that affects both public health and economic growth. The Chinese government has to prioritise its environmental issues over economic stability as the former provides a strong and fundamental foundation for the economy to thrive and sustain.  

China's Airpocalypse

The term ‘China Airpocalypse’ is genuinely adopted to describe the China smog 2015, and has probably gone viral in the internet and climate headlines since the beginning of the year. The nation, the northeastern region in particular, is suffering from climate and health impacts brought by the layer of smog persisted in the troposphere, yet the government seem helpless when dealing with the worsening air quality.  

Source: Australia Broadcasting Corporation 

Levels of air pollution in parts of the northeastern China hit dangerously high levels, with the concentration of fine particulate matter (PM 2.5) - the number of particulates 2.5 microns or less in width within each cubic meter of air - reaching 50 times the recommended safety limit in some regions (IFL Science). Shenyang, a major city in Liaoning Province, has reached a level of 1,400 micrograms of PM 2.5, despite the WHO recommends an average of 25 micrograms or less over 24-hour period listed in its air quality guidelines. Shanghai city’s air quality index (AQI) rose above 300, a level deemed hazardous on most scales and which can have a long-term impact on health, while levels of PM 2.5 reached a record high level of 281 since January, and city authorities have issued a yellow alert advising all elderly, young and sick residents to remain indoor, which includes shut down of school events of the day. Making it sound worse, Beijing issued the capital’s ‘first red alert’ in the face of hazardous pollution levels last week, suggesting restricted vehicles on the roads, heavy vehicles banned and class dismissal. 

The video gives a general picture of how it looks like in China now. 

And I came across this video below the other day, and found it quite interesting how a local artist wished to raise public awareness on the city’s catastrophic air pollution issue by literally vacuuming  dusts in the air using an industrial vacuum, and produced a solid brick using the matter he collected. The fact that shocks me most is that how local people become indifferent to the problem and treat it as part of their daily lives. This may be part of the problem why the Chinese government is so ineffective and inefficient in tackling air pollution issues. 

The China Smog is also recognised as the ‘sulphurous smog’, the same type of smog as the London’s Great Smog in 1952. It results from a high concentration of fine particulate matter including spheroidal carbonaceous particles (SCPs) and sulphur oxides, produced by combustion of fossil fuels (particularly coal) during industrial production. The smog can be aggravated by increased humidity and concentration of suspended particulate matter in the atmosphere. 

It is beyond disputes that the air pollution in China is contributing to the region’s, or maybe even the world’s climate change. Apart from the major climate-forcing effect (suspended particulate matter, also known as black carbons (BC), absorbs solar radiation and warms up the atmosphere) and other indirect effects like the surface albedo effect (interaction of BC and ice/snow crystals leads to melting of snow and hence positive climate forcing) and the BC cloud effect (interaction of BC and clouds alters cloud micro physics by changing the number of liquid cloud droplets that may eventually change precipitation patterns) that build upon the major effect (Bond T. C. et al. 2013), these fine particulate matter also cause health impacts that put our lives in imminent danger. 

According to WHO study, combustion-derived aerosols are particularly significant in terms of their health effects, causing respiratory and cardiovascular diseases in particular (Highwood E. J., Kinnersley R. P. 2006). A report from Berkeley Earth shows that air pollution in China contributes 17% of all deaths in China, causing an average of 4,000 deaths each day. The report also illustrates how breathing in Beijing when pollution is at its worst is equivalent to smoking one and a half cigarettes per hour.  

It is important for the Chinese government to seek realistic and effective measures to mitigate its air pollution problem. Quick fixes like cutting down industrial production is nonsense and is not economically feasible, and perhaps investing in greener energy sources and higher energy-efficient production would help reducing GHGs in the long-term. I shall propose any potential economic solution in my next post. 

More on the PBs...

Regarding the last entry on the framework of planetary boundaries (PBs) introduced by Will Steffen (2009), which provides a science-based analysis on the risk that current anthropogenic activities will destabilise, in other words, threaten the resilience of the Earth system to any abrupt environmental change, Steffen has provided an updated version of his PBs analysis in his recent paper: Planetary boundaries: Guiding human development on a changing planet (Steffen et. al 2015). The core concept of PB remains, whilst the framework of it has been modified to conceptualise the substantial risks that human perturbations are imposing to the Earth system at both regional and global scale in a more sophisticated way. 

Source: Steffen W. et. al (2015), Planetary boundaries: Cuiding human development on a changing planet 347 (6223)

Comparing to Steffen’s previous analysis, climate change, stratosphere ozone depletion and ocean acidification are the three PBs remain essentially unchanged, which the latter two remain below safety boundary (see Figure 1). He also combines nitrogen cycle and phosphorus cycle into the planetary boundary of biochemical flows, which phosphorus cycle has drastically increased and reached beyond zone of uncertainty, as compared to previous studies. This gives climate change, biosphere integrity and biochemical flows remain beyond zone of uncertainty, with land-system change in the zone of uncertainty. 

As being one of the core PBs apart from climate change, Steffen has replaced ‘rate of biodiversity loss’ in his previous study by ‘biosphere integrity’, which is an aggregate of genetic diversity and functional diversity. Changes in genetic diversity and functional diversity impose different subsequent impacts on the Earth system, however the long-term concept is to achieve biosphere integrity - the combination of both below safety boundary to guarantee biodiversity and stable Earth system. The former ensures the complexity and long-term capacity of the biosphere to resile from abrupt or gradual environmental changes, while the latter manifests the role of biosphere in Earth system functioning (Steffen et. al 2015). Although a  global decline in species richness (genetic diversity) will not result in impaired functioning of the world’s ecosystem (Brook et. al, 2010), partly because of constant introduction of new species to replace native / generic species, it is arguable that complexity and diversity is key to the integrity and stability of the Earth system, which then improves its resilience (Polis, 1998).  

Source: Polis (1998) Nature 395 (6704), 744-45

Figure 2 shows a food-web complexity on a island in the Gulf of California, which illustrates an interwoven interactions between species in wet El nino years. Marine sources and land plants provide the fuel for an estimated 500-1,000 species  (Polis, 1998). In this case, a complex food web helps to moderate population fluctuations and prevents species loss. Take the spiders from this food web as an example. Spiders relies on a range of feeding sources / prey such as scavenging insects, herbivorous insects, detritivorous insects and so on, and in case there is a reduction in herbivorous insects due to a fire that burns down hectares of land plants, they may shift to consume other resources. As such, having many prey does not only help to secure the consumer’s feeding sources, but also preventing consumers from driving any particular prey to extinction, and so enhancing the diversity and stability within the system. 

Although the new analysis from Steffen provides a more sophisticated framework in explaining the nine PBs, it has its limits and analysis has to be taken further. Firstly, data for the atmospheric aerosol loading is regional (focus on the case study of South Asian Monsoon) and so the predicted boundary shall not be reliable enough to representative at a global scale. To take it further, different regions have their own climate and monsoon system, levels of atmospheric aerosol should then have various impacts on different monsoon system. Secondly, the framework only provides a guidance of decision making in societal development without showing any potential results in the Earth system in the long term. Steffen made his framework of planetary boundary based on the Holocene climatic levels and may not be applicable to today’s development. The Earth system may evolve to a new state that is compatible with the changing climate like how they have been adapted to different climates during the interglacial periods. In addition, technologies advancement and innovations may help to improve biosphere resilience and diversity in the face of climate change. As such, the concern is not about how unstable the Earth system would be, but how destructive an unstable Earth system could be in affecting a human civilisation. 

Meanwhile, Steffen's framework provides a valuable contribution to decision making in charting desirable courses for societal and economic development.