Sunday, September 2, 2012

Can geoengineering help Africa’s climate fight?

Ours is a planet on fire.  Does that scare you?  If it does, then you will probably be one of those wondering why the last few months have been hotter than any you’ve experienced in your entire life time.  Many scientists will simply give one answer – global warming.
Though there still exists some strong opponents, consensus on global warming has grown in the last decade that many who once opposed it have become converts of some sort.
A report put out in November 2007 by the Intergovernmental Panel on Climate Change (IPCC) stated that around mid-2005 the world crossed a vital and dangerous climate threshold.  James Hansen of the United States’ National Aeronautics and Space Administration (NASA), whose findings supported the IPCC report described climate change as ‘great moral issue’ at par with slavery.  "We're in an emergency: you can see what's on the horizon over the next few decades with the effects it will have on ecosystems, sea level and species extinction."
Hansen, called the ‘godfather of global warming’ by some, is a controversial figure.  In a 1988 testimony to the U.S. Senate, Hansen predicted then that Washington DC, the US capital city, would experience nine days per year of high temperatures of 95 degrees or more this decade if greenhouse gases continued to rise. This year, even before August, Washington had 23 such days.
"When I testified before the Senate in the hot summer of 1988, I warned of the kind of future that climate change would bring to us and our planet. I painted a grim picture of the consequences of steadily increasing temperatures, driven by mankind’s use of fossil fuels.  My projections about increasing global temperature have been proved true. But I failed to fully explore how quickly that average rise would drive an increase in extreme weather," Hansen wrote in the Washington Post early this month.
Geoengineering techniques are very controversial: while some climate scientists believe they may prove a quick and relatively cheap way to slow global warming, others fear that when conducted in the upper atmosphere, they could irrevocably alter rainfall patterns and interfere with the earth's climate
One of those who share Hansen’s worry about human-induced climate change is Prof. Aberra Mogessie, president of the African Geological Society.  According to Mogessie, those who suggest climate change might not be happening are not heretics, but are guilty of a staggering lack of intellectual rigour.  The Ethiopian professor was one of the participants at a meeting of African scientists in Senegal aimed at xraying the science of solar geoengineering and its implication for Africa.
For the over 25 eminent African scientists that attended the workshop from at least 14 African countries, the debate wasn’t whether or not climate change is happening.  “The tendency to doubt climate change here in Africa is almost non-existent because we see its impact everyday on the continent, said Prof. Berhanu Abegaz, Executive Director of AAS, whose organization was the lead organizer of the workshop.
“There is no dearth of consensus on the fact that climate change is real; what we have in short supply are innovative ideas on how to mitigate its impact, and that’s why we are gathered today,” Abegaz said as he opened discussions on the issue of solar geoengineering, a nascent science for which there are as many proponents as there are opponents.
The science mostly refers to the deliberate and large-scale engineering and manipulation of the planetary environment to combat or counteract changes in atmospheric chemistry.  Geoengineering techniques are very controversial: while some climate scientists believe they may prove a quick and relatively cheap way to slow global warming, others fear that when conducted in the upper atmosphere, they could irrevocably alter rainfall patterns and interfere with the earth's climate.

According to Andrew Parker of UK’s Royal Society, the term geoengineering covers everything from mundane methods for increasing carbon storage in plants, soils and oceans to solar-radiation management (SRM) techniques — for example, creating haze in the stratosphere to act as a cheap layer of sunscreen.
Scientists say rising atmospheric concentration of greenhouse gases are the main causes of warming of the physical climate system.  “By removing greenhouse gases from the atmosphere it would be possible to reduce the speed at which the planet is warming,” Parker explains.
Speaking on the controversy over geoengineering, Ahmadou Lamine Ndiaye noted that objective assessment of the merits and demerits is necessary if any progress would be made on the subject.  “While we must not take the expressed fears about geoengineering for granted, it is important that fears do not lead to inaction.  Global warming is happening and happening fast irrespective of the global politics around it.  For us in the science community, what is required is a separation of the politics from the science,” said Ndiaye a former Senegalese minister who doubles as the president of AAS.
Prof. Oye Ibidapo-Obe, former Vice Chancellor of University of Lagos and president of the Nigeria Academy of Science, believes Africa needs to tap into growing interest in the science.  “It is important that Africa is not left behind in this science.  We must encourage research in this area as a necessary step to building continental consensus,” he said.
In the absence of adequate reductions in anthropogenic CO2 emissions, geo-engineering has been put forward as a major option that might fix the world’s rapidly changing climate. Geoengineering proposals are divided into two main groups: carbon dioxide removal (CDR) and solar radiation management (SRM).  CDR methods are carbon capture and storage systems that remove CO2 from the atmosphere without distorting natural systems.  They are considered safe, sustainable and less controversial aspect of geoengineering and come in the nature of bioenergy, biochar and reforestation among others.  CDR methods are generally considered slow to reduce global temperatures.
SRM, described by some critics as the ‘quick fix’ approach, remains the most controversial geoengineering method.  It aims to produce a reduced net radiative forcing by balancing the positive forcing of greenhouse gases with a negative forcing introduced by reducing absorbed solar radiation.
The Dakar workshop was an attempt by AAS and its partners to galvanize African perspectives on SRM. Ideas for SRM include increasing the amount of aerosols in the stratosphere, which could scatter incoming solar heat away from earth’s surface, or creating low-altitude marine clouds to reflect these same rays.
“To take geoengineering methods like solar radiation management seriously, we need to build realistic models,” said Prof. Ibidapo-Obe. He maintains that while it is premature to consider testing SRM at a very large, “it is not premature to understand what we can learn from such tests.”
Despite disagreement on when or whether geoengineering technologies should be used, participants generally agreed on the need to identify a responsible way forward for geoengineering research.
Given the nascent state of geoengineering technologies, it is unlikely that they may be applied in Africa soon.  It may take a while before the likes of Wade Youssou sees the kind of experiment the Bill Gates-funded scientists plan for New Mexico next year, but some participants at the Dakar workshop say any large-scale application of the technology is likely to impact Africa directly or indirectly.
Despite the surge in interest at present, no SRM proposal has been tested or even subjected to preliminary trials.  As the workshop participants agree, there is a need for some form of regulation of SRM at the global level. One quick trial in any part of the world may lead to some unilateral trials in different other countries, a situation some fear might not augur well for the entire global community.
“As the effects of SRM are not currently predictable with respect to their magnitude, location or details, such unilateral efforts could lead to international tension or even conflict. This is especially true since it will be difficult to establish whether any specific drought, flood or heat wave was or was not the consequence of SRM deployment,” warns Alex Hanafi of the Environment Defense Fund, whose organization is one of those in the forefront of campaigns for global governance of geoengineering.

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