Concerns related to SRM

Despite potential positive effects from SRM, there are also several concerns suggested by many studies. 

Controversies over stratospheric aerosol injection
One of the widely discussed concerns include the side effects of stratospheric aerosol injection. 

Impacts on regional climate
The idea of stratospheric aerosol injection has been initiated after analysing the effects of major volcanic eruptions such as Mt. Pinatubo eruption (1991), which cooled down the earth's temperature globally for few years without significant adverse impacts. However, later studies investigated that actually, there were major adverse effects following the Mt. Pinatubo eruption, suggested by Trenberth and Dai (2007): 
     After examining precipitation and streamflow records between 1950 and 2004, the study indicated that there has been a 'substantial decrease in precipitation over land and a record decrease in runoff and river discharge into the ocean' between October 1991 and September 1992 (Trenberth and Dai, 2007). Furthermore, it is also suggested that drought may arise as an adverse effect of geoengineering application. 

Confining the geoengineering region
Even if it is possible to control the exact amounts of aerosols injecting into the atmosphere - preferably less than amounts injected by volcanic eruptions - some questions still remain for answers; for example, is it possible to 'geoengineer' the isolated regions such as the Arctic and will the application be confined there? (Robock, 2008) Also, will the engineers and scientists be able to predict all the (adverse) effects beforehand while the question of confined geoengineering is unresolved? The adverse impacts of stratospheric aerosol injection may or may not be worse than predicted, but current simulations using different climate models reveal reduced precipitation over wide regions leading to the possibility of drought. 

Ozone depletion
Some scientists propose a threat of ozone depletion from stratospheric aerosol injection, since aerosol particles can serve as a surface for chemical reactions that may destroy the ozone layer of the Earth (Robock, 2008). If this happens, devastating effects on crops and natural flora will be massive. 

Yet, potential of SRM exerting positive influence also exists
However, other studies such as Modak and Bala (2014) signify that aerosol injection with different latitudinal distribution may be effective in reducing the impacts of climate change and global warming, although uncertainties in the process of injection/ transportation itself and particle size evolution over time exist. 


Even though there are lots of concerns raised for different SRM approaches, stratospheric aerosol injection seems to receive greater attention than others. It seems to me that further studies on adverse effects should continue to be researched, since it is better to know all the possible side effects that could happen before the actual application of SRM technologies; preventing before it cannot be reversed. 

Introduction to Geoengineering - SRM

What is Geoengineering and Solar Radiation Management?

As mentioned in the first post, Geoengineering often refers to 'large-scale efforts to diminish climate change from greenhouse gases that have already been released to the atmosphere' (Caldeira et al., 2013). It can be classified into two major categories, solar radiation management (SRM) and carbon dioxide removal (CDR) - this post will focus on SRM. 

Solar radiation management (SRM) targets to offset the effects of anthropogenic climate change, including high atmospheric CO2 and other greenhouse gases (GHGs) by reducing the amount of solar radiation absorbed by Earth. Since atmospheric CO2 and other GHGs deploy radiative forcing on the Earth's climate system through making harder for the heat coming in to escape from Earth (Caldeira et al., 2013). SRM approaches can be divided into four major kinds: 

     Space-based approaches introduces to reduce the incoming solar radiation reaching Earth, including the installment of mirrors and rings in orbit around the Earth by constellations of spacecraft (Pearson et al., 2006) or placing a thing glass shield using lunar materials near the first Lagrange point (L1) of the Earth-Sun system (Early, 1989). 

     Stratospheric aerosol-based approaches aim to inject sulfate aerosols into the lower stratosphere to cause scattering solar radiation back to space, leading to the cooling of Earth (Caldeira et al., 2013). This idea of injecting aerosols have suggested from looking at the past volcanic eruption such as Mount Pinatubo in 1991, which caused cooling of the earth's surface in following years by almost 0.5 degrees Celsius (Cruten 2006). Even though sulfate aerosol injection could be done in troposphere to cool the earth, it is considered to be more efficient to inject in the stratospheric due to their longer residence time of about 1 - 2 years - while only a week in troposphere - hence the required sulfur for cooling would be much less in the stratosphere injection, compared to the troposphere (Dickinson, 1996). 

     Marine cloud brightening is another way of modifying the reflectivity of the earth, particularly increasing the low-level marine stratocumulus cloud reflectivity (Caldeira et al., 2013). Studies on cloud albedo such as Twomey (1977) suggest that by increasing the number of cloud condensation nuclei (CCN), greater number of cloud droplets would be produced while the droplet size actually drops, then the total cloud droplet surface area will increase and thus the cloud reflectivity. Areas with extensive marine stratocumulus clouds such as the west coast of Africa have been distinguished with potential to adopt such SRM approach (Latham et al., 2008). 

     Surface albedo enhancement will be one of the most well known SRM strategies. It aims to increase the earth's surface albedo through altering the surface reflectivity of the ocean, deserts, urban and rural regions (Caldeira et al., 2013). Methods can range from whitening the roof of the buildings to planting more reflective plants. 

Different SRM strategies: a) using satellites to reflect the incoming radiation back to space, b) injecting sulfate aerosols into the stratosphere, c) marine stratocumulus cloud brightening, d) altering the ocean surface albedo, e) growing plants or crops with high albedo and f) whitening building roofs - adopted from (Caldeira et al., 2013). 

Many scientists advocating the implementation of geoengineering as an effective measure for responding to climate change claims that it can be used with other strategies (to reduce greenhouse gas emissions and increase adaptive resilience to climate change) to accelerate the pace of 'returning' the earth back to pre-industrial level. This may in part because rather 'quick' response of climate system to geoengineering is projected (Matthews & Caldeira, 2007) in computer simulations. Especially, SRM strategies such as whitening the roofs of the building or planting crops with high albedo can be implemented in a fairly easy way, anticipating for a quick response. Hence, some implies that there may be only a little cost in delaying the geoengineering deployment 'in the field' until the earth reaches a very 'dangerous' and imminent situation of climate change (Matthews & Caldeira, 2007).

     However, many oppositions for geoengineering implementation also exist, keeping the debate ongoing. Next post will explore about such debates and the other major geoengineering scheme of CDR.
 

COP22 in Marrakech - happening now!

UN Climate Change Conference 2016 in Marrakech, Morocco

I was going to move onto details about the methods and controversies of geoengineering, but cannot pass without mentioning about the UN climate talks happening now in Marrakech!

"This conference [COP22] comes within a climate of hope and of legitimate aspirations for all of humanity" said COP22 President and Morocco’s Foreign Minister Salaheddine Mezouar (left) at the opening of COP22 in Marrakesh, Morocco - with COP 21 President and France’s environment Minister in charge of climate-related international relations Ségolène Royal.
Source:UNFCCC

Marrakech conference as COP22, CMP12 & CMA1
UN Climate talk happening now in Marrakech serves as 22nd meeting of the Conference of Parties (COP22) to the UN Framework Convention on Climate Change (UNFCCC), 12th session of the COP serving as the Meeting of the Parties to the Kyoto Protocol (CMP12), and lastly the first meeting under the Paris Agreement (CMA1) discussing about the next step of Paris Agreement.

For Paris Agreement 'enter into force', it requires at least 55 'parties' that represents approximately 55% of global greenhouse gas (GHG) emissions and this was met on 5th October already - ready to be discussed during the conference. It has been compared with the Kyoto protocol, which took almost eight years for the 'entry into force', giving expectations for relatively 'smooth' discussions of Paris agreement action plans to be held.


Worthy of attention - fossil fuel companies as 'observer' in the climate conference
During the Marrakech conference, the representatives of global fossil companies including ExxonMobil, Chevron, Peabody energy, BP and Shell have unquestioned access to most of the discussions among delegates of countries and other interest groups. Some countries suggested that with high-GHG emission and fossil fuel companies who argued that they are willing to be as 'inclusive' as possible in the climate talks and also cooperate to minimise the 'conflict of interest'. 

Some questions about their 'real' intentions on this climate conference - are they truly there to encourage more strict regulations for fossil fuel industry that they create profits? 
Also, the contrast between the position of many fossil fuel companies in policy debates before the climate conference and now can be seen as almost 'ironic' - for example, when Peabody Energy went bankrupt, some of the court documents indicated that they were funding more than twenty groups (including trade associations, industry front groups and corporate lobby groups) that cast doubts on human impact on climate change and opposing views on environmental regulations and Peabody will be 'represented at the meeting by six bodies with observer status' (The Guardian, 2016). 

Yet, this view might be biased in some ways - fossil fuel companies might really want to participate in action against the climate change impacts happening..

More to be come from the conference as it is only the beginning!  

Here are the first press briefing with UNFCCC spokesman & COP22 president: 
http://unfccc.cloud.streamworld.de/webcast/unfccc-and-cop-22-president



References
https://www.theguardian.com/environment/planet-oz/2016/nov/05/whats-in-store-at-the-marrakech-climate-talks-and-will-australia-still-back-coal

https://www.theguardian.com/environment/2016/nov/07/marrakech-climate-talks-giving-the-fossil-fuel-lobby-a-seat-at-the-table

http://cop22.ma/en/#whatscop/post/166

Planetary Boundaries

Planetary Boundaries - global climate change management guidance for humans? 

Before moving on to investigating specific management skills for global climate change, I got interested in this idea of 'planetary boundaries' - let's explore this further!


Planetary boundaries
Planetary boundaries defines the "safe operating space for humanity with respect to the Earth system, associated with the planet's biophysical subsystems or processes" (Rockström et al., 2009). It is a recent approach introduced in science, proposing the preconditions for human development when environmental change and Earth's capacity to regulate conditions appropriate for human activities occurred during the Holocene. 
During the Holocene, planet earth had resilience to 'buffer' the disturbances caused by human developments; for example, half of the greenhouse gases emissions were taken up by the nature and much of the heat coming to the Earth were absorbed by the deep ocean. However, as humans have become the major force of change in planetary scale in current Anthropocene, planet earth starts to change and give positive feedbacks in various environments. To tackle this challenge, planetary boundary framework has been suggested. 

There are nine processes of Earth-system associated with major thresholds of the planet, including climate change, rate of biodiversity loss (terrestrial and marine), stratospheric ozone depletion, ocean acidification, global freshwater use, land use change, disturbances in nitrogen and phosphorus cycle, chemical pollution and atmospheric aerosol loading. Three out of nine boundaries are already transgressed currently (see Figure 1). 

Figure 1 - Planetary boundaries criteria - green shades are the proposed safe operating space for each of planetary systems and red wedges are the estimate of current position for each variable. Three systems' boundaries (Biodiversity loss rate, climate change and human interference with Nitrogen cycle) are already been exceeded currently. 
(Source: Rockström et al., 2009).

Studies on planetary boundaries suggest that if the threshold for earth-systems are exceeded, if will result in 'deleterious or potentially even disastrous consequences for humans' (Scheffer et al., 2001). 

Along with readings, I found and watched a TED talk by Johan Rockström, one of the leading scientists researching about the planetary boundaries; 

Are we bankrupting nature?  Johan Rockstrom at TEDxUppsalaUniversity (Source: https://www.youtube.com/watch?v=2Xc8WHtKBio)

During the talk, Johan mentions that us humans need to deeply consider not only about walking such huge 'transformation' that we are going through together, but also recognising that we are in a world where it reached the nature's saturation point and thus share remaining ecological space on Earth. Also, he suggests that it is time for humans to reconnect to the Biosphere, reversing the existing 'order' in human development and earth's environment - where humans are driving economic developments first and then reducing the environmental impacts - and moving onto the new paradigm of 'growth within limits'. 
I agreed to his thoughts and also thought that despite all those efforts to quantitatively and qualitatively define 'safe-operating' spaces of planet earth, if we humans do not start to change views looking at the planet and its values sustaining us, it will have only a little use in managing the degradation that is happening all over the world.  
We are very lucky to live within this diverse and rich biosphere where our society and economy can thrive, so now efforts for appreciating those spaces should be needed in such urgent situation. 




References:

Rockström, J., Steffen, W., Noone, K., Persson, Å., Chapin, F.S., Lambin, E.F., Lenton, T.M., Scheffer, M., Folke, C., Schellenhuber, H.J., Nykvist, B., De Wit, C.A., Hughes, T., Van Der Leeuw, S., Rodhe, H., Sörlin, S., Snyder, P.K., Costanza, R., Svedin, U., Falkenmark, M., Karlberg, L., Corell, R.W., Fabry V.J., Hansen, J., Walker, B., Liverman, D., Richardson, K., Crutzen, P., and Foley, J.A. 2009. A Safe Operating Space For Humanity. Nature. 461.7263: 472-475.

Scheffer, M., Carpenter, S. R., Foley, J. A., Folke C. & Walker, B. H. 2001. Catastrophic shifts in ecosystems. Nature 413: 591–596. 

Introduction

Welcome to my blog exploring the management of global environmental change :)

In this blog, I would like to investigate how global environmental change is affecting the lives on Earth and how it is being managed or planned to be managed - through looking at variety of aspects including geoengineering. 

Global environmental Change and Anthropocene

The trend in Earth's system is that there is an overall degradation (or decline) in the environment, ranging from the decline in the biodiversity of species to the disappearance of water sources such as the Aral sea. Recently, the scientific community begun to recognise that such trends are heavily influenced by the human activities happened since the birth of agrarian societies (although continuing debates exist about the beginning of such human-induced changes on earth), and a new notion of anthropocene has been introduced. 

Anthropocene

Anthropocene is a recent notion referring to the new geological epoch of the Earth after Holocene, when us, the humans, were starting to profoundly influence the Earth system. Unlike before, humans and their activities are beginning to be recognised as the major force affecting the 'trajectory of the Earth system instead of all the usual non-human forces of nature' (Maslin & Lewis 2015). There are ongoing debates on the definition and start of Anthropocene among scientists, but they all agree that this new epoch has already occurred on the planet. 

Here is a video explaining about the Anthropocene in a simple way:

Source: https://youtu.be/fvgG-pxlobk

Current global environmental change includes changes in climate itself, such as increase in the frequency of extreme climate events, warmer surface temperature and global sea level rise. Although there are controversies over whether such climate change are induced by natural forces like sun's forces and related orbital forces exist, it is widely accepted that the human activity are one of the major drivers of such global change. 

Following video clip introduces about the recent climate change induced by humans:

Source: https://youtu.be/EtW2rrLHs08

Managing global environmental change

As illustrated, the global shifts in Earth's environment - mostly devastating effects - are getting acknowledged by wider community and more efforts to manage such changes are implemented around the world. 

Global cooperation on emission and temperature limit

One of recent major global cooperation efforts on managing global climate change can be the Paris agreement happened last year. COP21 aimed for the first time for achieving a legally binding and universal agreement on global cooperation on climate change mitigation and adaptation, and the final draft of the Paris deal includes global limit on temperature of 'well below 2°C' with 'efforts' to limit it to 1.5°C. Additionally, long-term emissions goal is also included in the agreement that are more specific and tightly defined for global community compared to the previous drafts of climate conference. 

COP21 Paris agreement - Source: COP PARIS/Fliker https://www.flickr.com/photos/cop21/23595388112/in/album-72157661744003510/ 

Geoengineering 

Geoengineering that aims to manipulate the Earth's environment in a large-scale, has been suggested as a potential tool to mitigate global warming from (mainly anthropogenic) greenhouse gas emissions (Zhang et al., 2015). There are various aspects in geoengineering schemes including land-based, ocean-based, atmosphere-based and space-based approaches. One of most renowned schemes of geoengineering is the Carbon Capture and Storage (CCS) that target to remove carbon directly. It has already been developed and started to be applied in some parts of the world, including agriculture and forestry (Chaudry et al., 2013). 

Carbon Capture & sequestration 

Source: Mann & Kump, 2015. Dire Predictions: Understanding Climate Change, 2^nd Edition. Pearson Education. 

Despite its potential impacts on mitigating global environmental change, there are still ongoing debates continuing on geoengineering, and this would be examined further in next posts. 

Others?

After all, degradation in environments needs to be managed through various conservation works even though it seems late - but still, "better late than never". 
Many civil societies and NGOs are campaigning and working in the field for conservation works, especially for biodiversity loss. For instance, first global conservation priorities have been set at the The International Union for Conservation of Nature (IUCN) World Conservation Congress. The targets include promoting nature-based solutions to climate change and accounting for biodiversity conservation in renewable energy development (https://www.iucn.org/news/first-global-conservation-priorities-set-–-iucn-world-conservation-congress). 

More management schemes planned or implemented globally to be discussed in following posts. 

References:

Chaudhry, R., Fischlein, M., Larson, J., Hall, D.M., Peterson, T.R., Wilson, E.J., Stephens, 
J.C., 2013. Policy stakeholders' perceptions of carbon capture and storage: a comparison 
of four U.S. States. Journal of Cleaner Produdction. 52: 21 - 32.

Climate Change 101 with Bill Nye | National Geographic (Youtube). 2015. Available at: 

https://youtu.be/EtW2rrLHs08 [Accessed 23 Oct. 2016].

Cop21paris.org. COP 21 Paris France Sustainable Innovation Forum 2015 working with 

UNEP. [online] Available at: http://cop21paris.org [Accessed 23 Oct. 2016].

E-education.psu.edu.  Lesson 11 - Geoengineering. [online] Available at: https://www.e-

education.psu.edu/meteo469/?q=book/export/html/178 [Accessed 23 Oct. 2016].

Gadian, A. (2011). Geoengineering. Atmospheric Science Letters. 12(2): 161.

Maslin, M. and Lewis, S. 2015. Anthropocene: Earth System, geological, philosophical and 
political paradigm shifts. The Anthropocene Review. 2(2): 108 - 116. 

Rhodes, C. 2016. The 2015 Paris Climate Change Conference: COP21. sci prog, 99(1): 97-

104.

Welcome to the Anthropocene (Youtube). 2012. Available at: https://youtu.be/fvgG-pxlobk  

[Accessed 23 Oct. 2016]. 

Zhang, Z., Moore, J., Huisingh, D. and Zhao, Y. 2015. Review of geoengineering approaches 

to mitigating climate change. Journal of Cleaner Production. 103: 898-907.