"BCB Eco- and Geo-informatics Blogs" - 5 new articles
SABIF Workshop on ecological niche modeling by Dr Barend Erasmus 24 – 27 March 2009This course on niche modeling started as a START-funded climate change capacity development programme (www.aiaccproject.org), and then it was developed further into an MSc-level course on niche modeling. The primary form of instruction is by means of structured lectures and discussion and practical computer-based instruction. The data and software that we will use for this course is available on an ftp site (details will be provided), as well as on the lab PC that you will be using. The course is presented by Dr Barend Erasmus, from the School of Animal, Plant and Environmental Sciences at Wits. More background information at http://web.wits.ac.za/Academic/Science/APES/Staff/AcademicStaff/Erasmus/ Venue: GIS lab in the Department of Biodiversity and Conservation Biology at the University of the Western Cape. Aim: The aim of this course is to give you an appreciation of the theoretical issues underlying the modeling of species’ ranges at various scales in time and space, and skills to apply the appropriate model for a particular research question. At the end of this course you should: To understand the factors that determine the distribution of a species’ in space and time To understand the concept of a niche To be able to make an informed decision on what type of data, model and model validation is appropriate for a particular research question. To be able to perform a niche modeling analysis This short course will be both lectures and practical sessions. The course requires knowledge of Excel including use of the data analysis package and ArcView/ArcGIS and will include instruction on the use of the statistical package R. Here is the link to the programme: SABIF_course_outline_ed.pdf SABIF Workshop: Ecological niche modeling literature guidanceHere is a quick guide to use of the extensive literature on ecological niche modelling. The literature is available for a short period from this link. General Literature Gaston, KJ. 2001. The structure and dynamics of geographic ranges. Chapter 2. General principles of species’ ranges Austin 2002 Kolasa & Waltho 1998 Pearson & Dawson 2003 Guisan & Zimmerman 2001 Different types of models (Guisan & Zimmerman 2000) Model comparisons (Segurado & Araujo 2004), Thuiller et al 2003, Manel et al 1999) Spatial effects (Keitt et al 2002) Geographic data completeness (Peterson & Cohoon 1999) Environmental variable selection Whittingham et al 2003 Lobo et al 2002 Vaughan & Ormerod 2003 Olwoch et al 2003 Species distribution data Dennis & Shreeve 2003 Hirzel & Guisan 2002 Friar et al 2004 Brotons et al 2004 Engler et al 2004 Model calibration and evaluation Prevalence (Manel et al 2001) Training and testing data (Fielding & Bell 1997) Kappa (Fielding & Bell 1997) ROC (Fielding & Bell 1997) Maximising the AUC (Fielding & Bell 1997) True Skill Statistic (TSS) (Allouche et al 2006) Pearson et al 2006 Anderson et al 2003 Improving niche model outputs Include land cover (Pearson et al 2004) Include expert opinion (Anderson et al 2003) Include habitat loss (Pyke et al 2004) Include species interactions (Fox & Morin 2001) Include known paleodata (Hilbert et al 2004) BCB724: Personal versus Public Transport in South Africa.This assignment is for the 2008 class and replaces the assignment on South African issues that was done in the 2007 class. The privately own motor car is one of the most visible agendas for addressing climate change concerns (especially carbon emissions). Most manufacturers are investing considerable Research and Development budgets into alternative propulsions from hybrid cars to use of the hydrogen fuel cell. Re-engineering conventional engines, especially modern diesel engines is also fertile opportunities for car manufacturers. When there is any re-engineering involve costs obviously escalate. Consequently it is not surprising the hybrid cars and modern diesel cars are still more expensive to purchase. One other problem is the expense of the car to manufacture , technologically the Toyota Prius is one of the most efficient cars on the road (good fuel consumption and low carbon emissions) but its manufacture is environmentally expensive. To illustrate a Prius sold in North America is partly powered by batteries where the nickel was mined/smelted in Canada (Sudbury) which has historically seen much environmental damage, although not as much as claimed. This Nickel is shipped to Europe for further refinement then goes to China to made into “Nickel Foam” and then onto Japan to be used to complete the manufacture of the batteries. The entire car is then exported from Japan back to North America. In pure energy terms a Toyota Prius costs twice as much to produce as a GM Hummer (the Prius’ antithesis). During operation it does indeed save energy over nearly all other vehicles – but the benefits only accrue (to balance the negatives) after 50 000 to 60 000 km. Unfortunately the Prius has an operational life expectancy of only about 160 000 km, whereas theoretically a Hummer should last up to 450 000 km. Although there have been articles say that a Hummer is more environmentally friendly - this blatant mis-representation. So it is important that you maintain a healthy scientific scepticism since so much of the material carries an agenda that obscures the basic facts. Any analysis should develop a cradle to grave approach to producing a green car. Generally the cheaper the car the less it costs in terms of energy to manufacture. Consequently a car that is smaller, lighter and cheaper to produce, with good fuel economy and good reliability (e.g. good customer satisfaction ratings), even if it is fairly conventional in construction is possibly greener than many green car. On the South African market which are the best green candidate? In South Africa precise measurements of the amount of C02 emitted have not been determined. Car Magazine uses fuel consumption as a proxy for C02 , however C02 is not the only greenhouse gas emitted since the exhaust produces methane and nitrous oxides. Vehicles with more efficient catalysts in their exhaust systems will be greener than others. In very basic terms, smaller, more fuel efficient and less expensive cars are currently about the greenest, the more reliable they are the better. Currently in SA you could argue that the Daihatsu Charade costing R87 000 returning 5.3 l/100km and releasing 123 g of C02 per km is the greenest car (it is jointly the most economical car in SA, shared with the Toyota Prius which costs more than three times.) Not everyone’s circumstances will suit a small hatchback with only four seats and 120 litre of luggage space. Internationally the greenest non-electric car, at least in terms of emissions is the Smart diesel with 88 g of C02 per km, followed by Volkswagen/Seat Polo/Ibiza bluemotion/ecomotion with 99 g of C02 the new Mini diesel with 104g of C02. None of these are available in South Africa. So in South Africa the actual lowest emission cars are the Peugeot 107/Citroen C1 followed by the smart cars with 112 g of C02 and our trusty Daihatsu Charade mentioned above with 114 g of C02. Of course, if you need a small family car the Toyota Prius leads with 104g of C02. Surprisingly the Ford Focus diesel in next with 114g of C02 but it will set you back some R220 000. Audi A3 and the BMW 1 series in diesel flavours are also good at 119g of C02. Up-scaling to a family car, we find that none of the 10 most efficient ones are available in South Africa. The figures that I have used are based on the UK Vehicle certification agency which uses these for vehicle licensing. A vehicle with less than 100 g of CO2 will have no road tax, as a car’s CO2 footprint increases so does its road tax. In South Africa there are no such incentives and we still seem to like cars with more power than our European counterparts – so larger bodied car with smaller and more economical engines have never sold well. Toyota SA has admitted that it is very disappointed with sales of the Toyota Prius. This is hardly surprising at close to R300 000 and with life expectancy of 160 000 km and it should not be driven on un-tarred roads, the surprising aspect is that more than 400 have been sold. In South Africa we share American tastes for SUVs and large Pick-up vehicles. Even the most considerate of these beasts such as the Lexus Hybrid uses 191 g of CO2 with Hummer using more than 500 g of CO2. Italian supercars like the Lamborghini and Ferrari are also in this territory. Unfortunately older cars are also much more polluting (due to engine wear and design), so a 10 year old VW Fox is putting out about 240 g of CO2. Even new cars such as Fiat Palio of an older design emit about 240g C02 right off the showroom (many Chinese manufactured cars are particularly bad in this regard given their small engines). So what do you do if you are on UWC lecturer’s salary or similarly low-salaried job? The first option is public transport which I will not deal with as it will be part of the assignment. Next small motorcycles/mopeds/scooters spring to mind. They also have a fairly low initial capital cost. Our market has been flooded with a multitude of Chinese-produced scooters . Certainly these bikes use between 3 to 5 litre of fuel per 100 km so you can estimate that the cleanest of these will produce about 60-70 g of CO2. A new, small commuter motorcycle, like Kazasaki’s 250 is only about as good as the best small cars we have (Peugeot 107 or Daihatsu Charade). I looked into the economics and certainly the Chinese flavours of scooters were not so good on running costs with service intervals of every 2000 to 3000 kms and replacement of the belt drives from 10 000 kms onwards even though their initial purchase price was low. Insurance of two wheels is generally higher so cost of ownership is more but you are, nevertheless, doing your little bit for the environment if you regularly used these rather than a normal car. What is the best form of personal transport for the environmentally conscious among us who are also not on large salaries? Well it seems that buying a not too old small second hand of modern design (remember a VW Citi Golf or Toyota Tazz are not particularly good) like a Daihatsu Charade or the two seater flavours of smart cars is about the best bet. Even a Ford Ka is not particularly great as its engine is fairly old technology, whereas a diesel flavoured VW Polo/Golf or Peugeot, Renault or Citroen is also a very good choice. The new Ford and Fiat diesels are also good choices with respect to low emissions. Buying a second hand car means a) it has already made its carbon debt in terms of its manufacture and once they have done between 40 000 to 60 000 km it has offset it construction costs in carbon so its cost to the environment is only its operation until the end of its life when the cost of re-cycling becomes incurred. Again smaller cars have less mass requiring re-cycling and in this regard interesting Mercedes are one of the best manufacturers. If you start including factory conditions then the new smart village that manufactures smart cars is the world leader and these cars have a very high percentage of recyclable parts. Arguably a smart car is actually the most green car – especially if and when the diesel versions come to South Africa. It is no wonder that North America is now witnessing the introduction of these cars and with fuel consumption as low as 3.3 litre/100 km which is as good as the most economical mopeds. I wonder which celebrity will opt to use a smart car as their mode of transport? In the UK the racing legend Sir Stirling Moss has just taken delivery of a new smart cart to augment his scooter. Sadly for South Africa our diesel fuels are still to sulphurous, and this is the main reason why many of the modern diesels cannot yet be introduced into South Africa. Of course driving a diesel in South Africa while good for the pocket and better in terms of carbon emission is still environmental damaging since they have increased sulphur emissions compared to petrol cars and that contributes to acid rain. No one has provided me with a reason why our fuel in South Africa imported from the Gulf region is more sulpherous than the fuel that USA and Europe imports from the same region? Are we reaching the limits to economy that personal transport can offer. There is actually still some way to go. Volkswagen have demonstrated a working prototype diesel that can run on as little as 1 liter per 100 km which could be introduced in 2010 with an estimated cost of close to 30 000 Euros (R367 693.00 before tax and transit costs) and makes use of lots of carbon fibre. The Aptera electric and hybrid cars are already available to Californians for $27 000 and $30 000 respectively (R209 000 and R230 000 before tax and transit costs) with hybrid getting less than 1 liter per 100 km. Be it 30 000 Euros or US dollars this is hardly affordable motoring and both vehicles only have room for two adults, although the Aptera can accommodate a pet or small child behind the front seats . Personally I find the Aptera rather more cool as it even has a solar roof to augment it batteries and it looks good and it is also made from carbon composites and protects it occupants like the cell used in an F1 car. Interestingly its lead designer was on the smart two seater project and it has an interior that is iPod cool. Rather more down to earth than the above esoteric cars, is MDI cars which use compressed air technology - with air being stored under pressure in carbon fibre tanks. The MiniCAT is a smart car sized three seater that will cost about 9 200 Euros (R112,000 before tax and transit costs). These come in various flavours of only compressed air for city use to use of small motors to make the compressed air to provide the propulsion. These latter hybrids achieve less than 2 litre per 100km and huge ranges like Cape Town to Durban on a single tank! Rather bigger is the CityCAT that has multi-platforms from a double-cabin pick-up, a sedan or taxi through to a station wagon or van by changing the rear hardtop section and a few interior elements and the estimated prices appear to be competitive with conventional cars. Of course innovative cars have been produced in the past and possibly the most fuel efficient was the Peel P50 and Trident which also managed about 2.5 litre per 100 km. The smaller of these was only 1.34m in length, 0.99m in width and had a mass of just 59 kg. However, being two stroke they still pollute the environment significantly more than modern four-strokes. Hopefully I have explained that going green when it comes to motoring is rather more complicated and will no doubt confuse the average person on the street. Now I will get to your assignment. Should the Tata Nano being introduced to South Africa? At the beginning of this year Tata corporation of India launched its Nano – a small car that is precisely 50% of the cost of the world’s next cheapest car called a Chery QQ built in China (which has raised a trademark dispute due to its similarities to the Daewoo/Chevrolet Matiz). In South Africa with its current import duties and VAT these Tata could potentially be marketed at R30 000. Tax relief could lowered this to as little as R22 000 (R17 000 in India), especially if accompanied by an incentive to remove old and un-roadworthy cars. Should this car be introduced to South Africa? It provide accessible motoring to many in terms of economics, fuel/energy efficiency and being so small in length (3m) and width(1.5m). In analysing whether these car should be introduced you need to consider all viable alternative options, implications for the design of our urban environment, road systems and solutions that do not involve the use of personal transport. It would be good to analyse how similar cars in the past have influenced economies and the urban environment (physically, economically and culturally). Your analysis needs to examine both economics and the impact on the environment. As a start to your analysis this is what Wikipedia has to say. As the Nano was conceived and designed around introducing the automobile to a sector of the population who are currently using eco-friendly bicycles and motorcycles, environmentalists are concerned that its extraordinarily low price might lead to mass motorization in countries like India and therefore possibly aggravate pollution and global warming as well as increase the demand for oil. Rajendra Pachauri, an Indian and chairman of the Intergovernmental Panel on Climate Change, said he was “having nightmares” because of this car and added that the car represents bankruptcy of India’s environmental policy. The ecology focused German newspaper die tageszeitung feels that such concerns are “inappropriate” as the Tata Nano has lower emissions compared to the average Volkswagen, and that developing countries shouldn’t be denied the right to motorized mobility when industrialized countries should be looking to reduce their emissions and usage of cars. Die Welt reports that the car conforms with environmental protection, and will have the lowest emissions in India. In crowded metropolitan cities like Mumbai, Ratan Tata has conceived a scheme to only offer the Nano to those individuals who do not have an automobile already. The Nano will also replace many overloaded and worn-out two-stroke polluting vehicles, both two and three-wheeled. In the current policy and regulatory framework, Centre for Science and Environment consider that the low-cost cars will be disastrous. This can change if renewable energies are used. Tata Motors is working with a French firm on using compressed air as fuel. Wikipedia contributors. Tata Nano [Internet]. Wikipedia, The Free Encyclopedia; 2008 Jul 11, 05:16 UTC [cited 2008 Jul 11]. Available from: http://en.wikipedia.org/w/index.php?title=Tata_Nano&oldid=224960359. In South Africa there has been mixed response to the possibility of Tatas being introduced - see comments at these two sites. http://www.motoring.co.za./index.php?fSectionId=751&fArticleId=4201934 http://www.motoring.co.za/index.php?fSectionId=1566&fArticleId=4226061 Your posting needs to be about 1500 words with careful referencing including peer-reviewed articles. It will be assess on depth of analysis and logic of arguments as well as originality. You are advised to work on your own, as many assignments appear to be little more than a combination of class views. There is an enormous range of alternatives for consideration ensuring each assignment represents a unique and individual perspective. Referencing must conform to CSE style. Yvonne: Global warming-a great swindle?Are man-produced emissions of green house gases, particularly carbon dioxide, responsible for the changes in climate that we are observing today? The 2007 movie “The Great Global Warming Swindle” released by Britain’s Channel 4, states categorically that we are not, attacking some of the basic science of climate change in addition to making several assertions about the political forces driving the idea of man-made climate change. In this paper, I will look at some of the evidence presented in the movie and compare it with three peer reviewed scientific publications on the science of climate change. Introduction “The Great Global Warming Swindle”, released in 2007 was a response to Al Gore’s movie, “An Inconvenient Truth” which opined that humans were responsible for the changes in global climate that can be seen today. The premise of “The Great Global Warming Swindle” was that humans are not responsible for changes in climate. I will look at three arguments in the movie and compare them with scientific papers on the same topics. These are: 1. Climatic changes in the past few thousand years cannot be linked in any way to human activity 2. The sun is primarily responsible for changes in climate through mechanisms such as cosmic ray activity and cloud formation. 3. The amount of carbon dioxide produced by anthropogenic sources and its possible effect on the climate system: The movie argues that influence of carbon dioxide on climate change is very small due to the minute amounts of carbon dioxide that exist in the atmosphere. Even if carbon dioxide has a link to climate change, humans only release a small fraction of that amount, with oceans and living organisms producing significantly larger amounts. Could Humans have been responsible for changes in climate in the past few thousand years? According to the makers of the film, changes in the climate in the past few thousand years, including the Little Ice Age, the Medieval warm period and the Holocene maximum occurred without the help of humans and were part of the natural changes always occurring in the climate system. [ Dr Piers Corbyn, Climate Forecaster, Weather Action ] None of the major climate changes in the last thousand years can be explained by CO2. [ Professor Ian Clark ] You can’t say that CO2 will drive climate. It certainly never did in the past. The crux of their argument is that past changes in climate could not have been caused by human impacts. This is the backbone of their argument that humans are not responsible for the changes in climate that we see now. However, in a paper by Rudimann in 2006 [1], the author explains that there were changes in the atmospheric concentrations of two key green house gases during those periods (Carbon Dioxide and Methane) and these may have been responsible for the warming experienced during that time. Departures from decreases predicted from the 23,000 year methane cycle during the Holocene may have been caused by human adoption of rice cultivation as far back as 7,500 years BP and subsequent development of irrigation around the time of the Holocene maximum. Around the same time of the Holocene maximum, carbon dioxide levels also began to undergo what the author terms “an anomalous increase” in concentration which far exceeded increases in previous interglacial periods. Rudimann dismissed two previously hypotheses previously put forward to explain CO2 increases during the Holocene. The first is that loss of terrestrial biomass due to expansion of tundra led to increases in atmospheric CO2. However, Rudimann argues that the net change in global carbon was small because increases in tropical rainforest biomass and carbon storage in the soil beneath the expanding tundra compensated for the biomass lost in the higher latitudes. The second hypothesis is that changes in ocean-carbonate chemistry before and during the Holocene were responsible for these changes. Late glacial forest growth extracted CO2 from the “oceanic-atmospheric system” causing the oceans to become less acidic and deposit CaCO3 along the ocean floor. Forest expansion stopped about 8,000 years BP leading to acidification of the ocean due to increased CO2 in the atmosphere and the release of deposited CaCO3 from the oceans. Thus CO2 increase was a process of ocean recovery from changes in the system. However, Ruddiman argues that the CO2 rebound effect from 8,000 years BP to present has been 4 times the amount of the early Holocene decrease which caused it. He also notes that previous deglaciations did not see the same increases in CO2 levels. Further, Ruddiman notes, increases in CO2 levels during the industrial level could not have occurred due to human input from industrialization alone. He argues that pre-industrial levels had increased steadily over the years due to agriculture and could account for the large values of these increases. Rudimann hypothesizes that pre-industrial clearance of forests in Eurasia was responsible for the CO2 rise between 8,000 yeas BP and 1800 AD. By putting this hypothesis to several tests, the author believes that the evidence supports it. These tests are: 1. Clearance must have begun about 8,000 years BP on a small but significant scale. Observations in the pollen record support this and indicate that changes were taking place in Europe, China and India around the same time due to forest clearance for agriculture (e.g. [2]). 2. Clearance must have grown enough by 2000 years BP to explain 80% of pre-industrial CO2. Developments in agriculture such as irrigation, the domestication of horses, creation of tools from the Bronze and Iron age all happened between 6,000 and 2,500 years BP [3]. These advances, which led to the formation of cities and farming communities, also led to vastly larger scales of land-clearance which can be observed today from pollen records showing changes in natural vegetation 5,000 to 3,000 years BP [4], information on sediment accumulation on the Mediterranean coast from deforested watersheds around 3000-1700 years BP [5]. 3. Ruddiman then attempts to account for the CO2 minima that occurred after 2000 years BP. He hypothesizes that a mechanism that caused a reverse in CO2 emissions in a relatively short timescale (a century or less) had to involve some major impact on human populations that appeared and disappeared in such a time span. The one factor that may have had such an effect was the bubonic plague which arose in several pandemics, one wiping out about 25% of the population of Europe and North Africa (The plague of the Justinian 540-542 AD) and the other killing 25-33% of the population in the middle East and Europe (1347-1352) [6]. Ruddiman proposes that the mechanism which links these pandemics (and other smaller ones which also had an impact) to the 4-10 ppm decrease in CO2 levels is the sequestration of carbon by forests growth which occurred when farms were abandoned during this time along with the carbon dioxide stored in the deep ocean at this time. Is Solar activity solely responsible for changes in climate? [ Professor Philip Stott ] Isn’t it bizarre to think that it’s humans, you know, when we’re filling up our car, turning on our lights, that we’re the ones controlling climate. Just look in the sky. Look at that massive thing, the Sun. Even humans at our present six and a half billion are minute relative to that. In a paper by Laut [7], the author reviews some of the literature that has been written in support of the solar activity theory. He looks at the data, specifically graphs, that have been used to support these hypotheses and the ways in which they have been mishandled to arrive at conclusions against man-made anthropogenic climate change. Among the literature reviewed by the author is a paper by Eigel Friis-Christensen, one of the scientists interviewed for “The great Global Warming Swindle” [8] who later claimed that is data were misused by the movie’s makers. Laut looks at several hypotheses used in support of solar activity as the main driver of anthropogenic climate change: 1. Total cloud cover and galactic cosmic ray activity Laut reviews the work of Svenmark and Friis-Christensen in 1997 [9] and an update by Svenmark in 1998 [10] on the relationship between total cloud cover and galactic cosmic ray activity. Laut found that in these two previous papers, the authors made use of two data sets which they claimed represented total cloud cover. The graphs produced by the authors indicate that these datasets on cloud cover were correlated with and followed a similar trend to galactic cosmic ray intensity. In reality, the two datasets used represent different physical parameters. Data from the Defense Meteorological Satellite Data ( DMSP) do not follow the same trend as those from the International Satellite Cloud Climatology Project (ISCCP). The latter data combine stationary and orbiting satellites to give global coverage and are considered the most reliable data available on total cloud cover. The DMSP data used by Svenmark and Friis-Christensen show that cloud cover for 1992 was very high while those of ISCCP show a marked decrease in total cloud cover for the same period. Laut replotted the data provided by Svenmark 1998 [10] in order to show the differences in trend between the two data sets (Fig 1a, 1b). This supported a study by Kristjansson and Kristiansen in 2000 [11] showed that the original graphs used two incongruous sets of data (DMSP and ISCCP) in order to arrive at an agreement of a correlation between total cloud cover and galactic cosmic ray activity. Figure 1a: Replotted graph of original representation by Svenmark and Friis-Christensen showing a correlation between total cloud cover and galactic cosmic ray activity [7] Figure 1b: Graph of DMSP and ISCCP data showing a downward trend in the latter, which does not support Svenmark and Friis-Christensens graphs showing an increase in cloud cover from the period of 1992 [7] 2. Low cloud cover and galactic cosmic ray activity Another paper by Marsh and Svenmark [12], postulated a new hypothesis that it was low cloud cover rather than total cloud cover that influenced galactic cosmic ray activity as represented by data from a Peruvian station called Huancayo. However, the graph produced by Marsh and Svenmark (Fig 2a) from the Huancayo data was different from a subsequent graph produced Krisjansson et al [13] from the same data (Fig 2b). Fig 2c is a smoothed out version of the same data which shows a difference in the data trend. Laut points out some issues regarding the hypothesis of correlation between cloud cover and galactic cosmic ray activity. First of all, correlation between the two is questionable after 1989 and absent after 1994. Second, Marsh and Svenmark’s graph shows a half year delay between low cloud cover and GCRI. However, a current theory on the formation of cloud cover [14] suggests that is forms in less than a day after an increase in GCRI. Thus this delay in cloud formation after GCRI is not possible. Finally, difficulty in analysis of low cloud cover data gathered from satellites means that an inaccuracy of a few percent could “entirely spoil the agreement” showed by Svenmark and Marsh’s graph. Kristjansson et al [13] compared the correlation between low cloud cover and two parameters connected with Solar activity; total solar irradiance and galactic cosmic ray activity. They found a higher correlation between low cloud cover and total solar irradiance (r=0.8) than between low cloud cover and GCRI (r=0.47). Thus, Laut argues, the correlation found by Svenmark and Marsh could be a result of the relationship between total solar irradiance and low cloud cover which could imply the relationship between GCRI and low cloud cover since both are related to solar activity. Figure 2a: Reproduced graph from one by Marsh and Svenmark which showed a correlation between low cloud cover and galactic cosmic ray activity [7] [12] Figure 2b:Graph produced by Krisjansson et al from the same data as used to produce figure 2a above. This new graph showed that low cloud cover and galactic cosmic ray activity were not in strong agreement after 1989 and were in disagreement after 1994 [7][11]. Figure 2c: A smoothed out graph produced by Laut [7] to show more clearly the difference between the two graphs (2a and 2b) 3. Solar cycle length and Northern hemisphere land temperatures (1991) In a paper in 1991, Friis-Christiansen and Lassen found a “strikingly good agreement” [15] between solar cycle lengths and Northern Hemisphere land air temperatures. Again, as Laut points out, they use two sets of incompatible data. In this case their graph on solar cycle lengths is built from strongly smoothed data for the first 20 points which represent 55 years and directly observed physical data for the last four points from around 1970 (Fig 3). Thus the rise in solar cycle length which corresponds with global warming from the 1970’s was artificially created. Corrected values obtained by Laut by improving the smoothing to correspond to observed and predicted eras produces a graph which shows a decrease in solar cycle length from the 1970’s. This would have led to global cooling, rather than warming as postulated by Friis-Christensen and Lassen. Figure 3: Recreated graph of Friis-Christensen and Lassen’s graph which was artificially created using two sets of incongruent data, the first set for the first 20 points and the other for the last four points in order to show an increase in solar cycle length. 4. Solar cycle length and Northern hemisphere land temperatures (1995) In an update of their 1991 paper, Friis-Christensen and Lassen [16], the authors used as their central figure, a graph that consisted of two sets of data that were inconsistent in time scale. The first series of data from 1585 to 1866 and the second from 1862 to 1982 are separated by a 0.1oC anomaly caused by the differing timescales. However, the authors were able to obtain one curve from the two by manual lifting of one graph to correspond to the others, rather than by linear regression which should have been used. This mishandling of the data is used to give a false impression of a correlation between solar cycle activity and land temperatures in the Northern hemisphere. 5. Solar cycle length and Northern hemisphere land temperatures (2000) The final update of Friis-Christensen and Lassen’s 1991 report [17] was also a response to an article by Laut and Gundermann [18] critising the use of data in their original report. In a review by Laut and Gundermann [19], the authors found that the figures used by Friis-Christensen and Lassen used weighting factors of zero or close to zero for their solar data for the first 230 years of the solar record. Laut and Gundermann [19] argued that data with such a low weighting factor should not have been used. Friis-Christensen and Lassen [17] also doubled the number of data points from 1850 to 1980 which affects the linear regression of this part of the data, forcing it to correlate to temperature changes at the expense of other data points. The data were therefore not assigned equal weight factors which influenced the result. How much Carbon Dioxide are humans releasing into the atmosphere and what are its effects on the system? Another claim made by the makers of the Great Global Warming Swindle, is that we humans do not emit as much carbon dioxide into the atmosphere as other sources including living organisms, volcanoes and the oceans. However, they clearly miss the point which is that the global carbon cycle is a complex system which is sensitive to any perturbations. This system is controlled by factors from the biosphere, hydrosphere and geosphere which interact in complex and as yet not fully understood ways. Falkowski et al [20] gave an excellent review of the effects of the components of the earth’s system (both natural and man-made) in the global carbon cycle. The authors point out that the carbon cycle has been significantly altered and is now at a higher concentration than it has been in the past 420,000 years [21] as evidenced by ice core data. What impacts these changes in carbon dioxide may have on the climate system is what cannot be clearly predicted. What is clear is that carbon sinks such as the oceans and the ecosphere may not be able to absorb efficiently above a certain threshold due to the sensitivity of solubility pumps. Biological pumps in the form of carbon dioxide may increase in efficiency to counteract the inefficiency of the solubility pumps but these changes may not be able to cope with increasing levels of atmospheric carbon dioxide. In addition, because so little is known about the distribution and abundance of key marine organisms, we cannot specific responses of the biological pump system. If the oceanic system cannot cope with these changes, terrestrial systems may be left to bear the bulk of absorbing carbon dioxide emissions. Terrestrial systems on the other hand, have been vastly affected by land-use and other changes which could compromise their ability to act as carbon sinks, a result that is also extremely difficult to predict [22]. In fact, recent studies have shown that increasing temperatures may convert carbon sinks into carbon sources [23]. Lack of a full understanding of other biogeochemical cycles and feedback mechanisms within the system also means that the effects of these changes on the system cannot be fully predicted. With this degree of uncertainty on the earth’s systems and the effects of changes in carbon dioxide concentration, it would be unwise to continue to alter the system so recklessly. Conclusion The makers of “The Great Global Warming Swindle” misrepresent the facts about global warming in order to deny a link between anthropogenic emissions of Carbon Dioxide and the observed changes in climate that are currently being observed predicted to worsen. While presenting a variety of information skillfully crafted to appear genuine, they mislead the audience on the science of global climate change. The fact remains that humans are altering the balance of carbon dioxide in the atmosphere in addition to other systems such as the biosphere and the atmosphere. These systems work in a delicate balance which is sensitive to small changes within it. Cautionary and mitigating measures must thus be used to ensure that we do not perturb the system any further even as we seek to better understand these systems and the feedback mechanisms that work within them. References 1. Ruddiman WF. 2003. The Anthropogenic Greenhouse Era began Thousands of years ago. Climatic Change 61: 261–293. 2. Ren G. Beug HJ. 2002. Mapping Holocene Pollen and Vegetation of China. Quaterly Science Review 21: 1395 3. Sherratt A (Ed). 1980. Cambridge Encyclopedia of Archeology. Cambridge Univ. Press: Cambridge. 4. Huntley B, Birks HJB. 1983. An Atlas of Past and Present Pollen Maps for Europe: 0–13000 Years Ago, Cambridge Univ. Press: Cambridge. 5. van Andel TH, Zangger E, Demitrack A.1990. Land Use and Soil Erosion in Prehistoric and Historical Greece Journal of Field Archeology 7: 389. 6. Taylor C. 1983.Village and Farmstead. George Phillip: London. 7. Laut P. 2003. Solar activity and terrestrial climate: an analysis of some purported correlations. Journal of Atmospheric and Solar-Terrestrial Physics 65: 801– 812 8.Wikipedia contributors. The Great Global Warming Swindle [Internet]. Wikipedia, The Free Encyclopedia; 2008 Aug 8, 11:22 UTC [cited 2008 Aug 14]. Available from: http://en.wikipedia.org/w/index.php?title=The_Great_Global_Warming_Swindle&oldid=230591547. 9. Svensmark H, Friis-Christensen E. 1997. Variation of cosmic ray flux and global cloud coverage—a missing link in solar-climate relationships. Journal of Atmospheric and Solar-Terrestrial Physics 59 (11): 1225–1232. 10. Svensmark H. 1998. Influence of cosmic rays on Earth’s climate. Physical Review Letters 22: 5027–5030. 11. Kristjansson JE, Kristiansen J. 2000. Is there a cosmic ray signal in recent variations in global cloudiness and cloud radiative forcing? Journal of Geophysical Research 105: 11851–11863. 12. Marsh ND, Svensmark H. 2000. Low cloud properties influenced by cosmic rays. Physical Review Letters 85 (23): 5004–5007. 13. Kristjansson JE., Staple A, Kristiansen J. 2002. A new look at possible connections between solar activity, clouds and climate. Geophysical Research Letters 29: 2107–2110. 14. Yu F, Turco RP. 2000. Ultrafine aerosol formation via ion-mediated nucleation. Geophysical Research Letters 27 (6): 883–886 15. Friis-Christensen E, Lassen K. 1991. Length of the solar cycle: an indicator of solar activity closely associated with climate. Science 254, 698–700. 16. Lassen K, Friis-Christensen E. 1995. Variability of the solar cycle length during the past 1ve centuries and the apparent association with terrestrial climate. Journal of Atmospheric and Solar-Terrestrial Physics 57 (8): 835–845. 17. Lassen K, Friis-Christensen E. 2000. Reply to the article “Solar cycle lengths and climate: a reference revisited” by P. Laut and J. Gundermann. Journal of Geophysical Research—Space 105 (A12): 27493–27495. 18. Laut P, Gundermann J. 2000a. Solar cycle lengths and climate: a reference revisited. Journal of Geophysical Research 105 (A12): 27489–27492. 19. Laut P, Gundermann J. 2000b. Is there a correlation between solar cycle lengths and terrestrial temperatures? Old claims and new results. The First Solar and Space Weather Euroconference: The Solar Cycle and Terrestrial Climate, European Space Agency: 189–191. 20. Falkowski P, Scholes RJ, Boyle E, Canadell J, Canfield D, Elser J, Gruber N, Hibbard K, Hogberg P, Linder S, Mackenzie FT, Moore III B, Pedersen T, Rosenthal Y, Seitzinger S, Smetacek V, Steffen W. The Global Carbon Cycle: A Test of Our Knowledge of Earth as a System. 2000 Science 290: 5490 21. Crowley T. 2000. Causes of climate change over the past 1000 years. Science 289 (5477): 270-277 22. Bazzaz FA. 2000. Annual Review of Ecological Systematics 21:167 23. Jarvis P, Linder S. 2000. Nature 405: 904 Assignment 3: How can we achieve a given standard?- Different instrumentsINCENTIVE REGULATORY BASED APPROACH The coal fired power generation industry of South Africa is Eskom. Eskom is a state owned enterprise that generates, transmits and distributes electricity locally and regionally (AICC report, 2005). It provides lowest- cost electricity and safe ways for combustion of low-grade coal. Eskom along with other state-owned enterprises has been corporative, now pays taxes and dividends and is subject to a shareholder performance contract. At the same time, the relationship of the state to the sector has been clarified through the creation of an independent electricity regulator that approves prices without political interference (Akinboade et al, 2003). Eskom use a number of power stations throughout South Africa to produce electricity (Beke, 2000). The major fuel source used by Eskom is coal. In 2001 alone they used 94.14 million tons of coal. The coal is commonly used because it is easily recoverable from reserves and negligent environmental regulation (Ashe, 2002); since the coal is mined locally it is cheap to use it. The country suffers from atmospheric pollution and produces large volumes of greenhouse gases. South Africa cause 2 percent of global greenhouse gas emission, though it has only 0.7 percent of the world’s population (Whyte, 1995). Most of the African rely on South Africa for the generation of power. Consequently it is the biggest polluter. The 90.6% of energy sector carbon dioxide on the continent is from South Africa. It is significant to change the statistics. The burning of low-grade coal has serious negative environmental and social impact on the community (AIDC). The burning of coal releases a number of gases. These are carbon dioxide (CO2), sulphur dioxide (SO2) and nitrogen oxides (NOx). It also releases particulate matter (Pm) of different sizes (Wilreker, 2004). The burning of coal results in one of the reasons there is global warming. The burning of coal also contributes to acid precipitation that damages the ecosystem (Whyte, 1995). The aim of an incentive based approach is to have an incorporated pollution control to ensure that all South Africans, both now and in the future, will have an environment which always accommodates for their well being (South African Government Information, 1997). Basically the government should ensure that South African citizens have a right to clean and healthy environment. When the government pays for using cleaner energy, it will help the customers to pay less when paying for the solar system to be installed (South African Government Information, 1997). The section 24 of the South African constitution states that everyone has a right to a safe environment in terms of their health and well being (National Electricity Regulator, 2005). Eskom is trying to reduce the pollution each and every year. They achieve this by decreasing the amount of particulate matter (dust) liberated when electricity is generated (Beke, 2000). Eskom wants the system operator costs to be divided between internally and externally driven costs (National Electricity Regulator, 2005). There must be a balance to be achieved in determining the length of time for each control; hence the amount of time between the reviews. When there are longer times to do reviews, there will be greater incentives to reduce costs and improve efficiency (National Electricity Regulator, 2005). The period which is suitable to give incentives is 3 years. It started on the1st of April 2006. Within the 3 year period impacts of any unanticipated events will be identified and analyzed (National Electricity Regulator, 2005). In order to move to incentive regulatory based approach National Energy Regulator used a revenue cap form of control for transmission. This was done in order to give business revenue certainty. In turn revenue certainty aids in minimizing the risks of business and lead to lower financial costs. In order to determine the following year’s revenue, the revenue of the initial year is adjusted by an inflation index less (or with) an X factor. X factor looks at an assessment of the scope for productivity improvements and any underlying changes in costs (National Electricity Regulator, 2005). The installation of sulfur removing stack scrubbers in coal power plants can help to reduce environmental effects (Whyte, 1995). The government wants the use a nuclear energy programme as an alternative to coal fired power stations (AIDC). According to Eskom MD for resources and strategy Eskom is currently exploring if it’s possible to use hydrogen to produce electricity as an alternative strategy. This is part of the Eskom’s initiative to promote sustainable development (Davenport, 2006). Eskom also plans to generate thousands of megawatts of base load power from solar energy, with the initial construction of a 100-MW solar demonstration power plant (Davenport, 2006). The study was conducted to determine the maximum power that could be generated through solar energy. Eskom in turn provides an incentive to customers that buy a more efficient water heating solution (Davenport, 2006). Eskom has also investigated the most advanced clean coal technology known as underground coal gasification (UCG), a pilot plant study at Majuba power station. UCG involves converting underground coal in situ into a combustible gas, which can be used as a fuel for generating power. The coal is ignited in a cavity underground and combustion maintained by means of oxygen and/or steam injected through boreholes, creating pressurized gas, which can be tapped. The technology has the advantage of obviating the need for mining, processing and transporting the coal, and also avoids the transportation and disposal of ash (Davenport, 2006). Eskom could continue to provide feedstock for the domestic power sector for many years to come. However, the government is now keen to inject a greater element of diversification into the sector. South African government now funds different research projects done to find new technologies to reduce CO2 emission. The fiscal incentives are not widespread. KEY WORDS Incentive is a financial or non-financial factor that gives people a motivation to take certain actions. People may be penalized or rewarded depending on the choices they make. Global warming is a result of the accumulation of natural greenhouse gases. This leads to an increase in the average global temperature, and then there will be changes in the world’s climate. The impacts are varied, but it is agreed that they will have a great negative effects on the environment Sustainable development: It is meeting today’s needs, without putting the future’s generation’s needs at risk. Basically today’s actions will have good impact on the future. References: • Ashe .B, (2002) South Africa’s Mammoth Electric Company Leads the Way in Utility Privatisation While Touting Sustainable Development, Earth Life Africa eThekwini. Online access [15 April 2008] Available from: http://www.corpwatch.org/article.php?id=3528 • Akinboade O.A., Niedermeier E.W., and Sibanda F (2003) Sustainable Development: The Case of Energy in South Africa,Department of Economics, University of South Africa. Online access [22 April 2008]. Available from: http://www.tradeknowledgenetwork.net/pdf/tkn_energy_south_africa.pdf • AICC (The African Institute of Corporate Citizenship) ReportCom (2005) Eskom Annual Report, 27 and 28 March, Cape Town and Johannesburg. Online access [20 April 2008]. Available from: http://www.aiccafrica.org/PDF%20files/eskom-report.doc • Beke A., (2000) Lower respiratory infections in children below 5 years in Mpumalanga, Online access [12 April 2008]. Available from: http://www.environment.gov.za/soer/reports/mpumalanga/overview/11-airqu.pdf • AIDC (Alternative Information and Development Centre). Implications of the government, restructuring and privatization of Eskom for service delivery of basic services for poor communities. Online access: 20 April 2008. Available from: http://www.aidc.org.za/?q=book/view/113 • Davenport .J. (2006) Eskom examines hydrogen as alternative energy source, online access 22 April 2008. Available from: http://www.engineeringnews.co.za/article.php?a_id=90965 • National Electricity Regulator (2005) Economic regulation of Transmission using incentive based regulation, online access: 23 April 2008. Available from: http://www.nersa.org.za/documents/Economic%20regulation%20of%20Transmission%20using%20incentive%20base%20(2).pdf • South African Government Information (1997). Discussion Document Towards a White Paper on Integrated Pollution Control and Waste Management, Dept. Environmental Affairs and Tourism. Online access: 14 April 2008]. Available from: http://www.info.gov.za/whitepapers/1997/pollution.htm • Wilreker G.I, (2004) A Comparative study of Emissions from coal-fired power stations in South Africa and Other selected countries, Rand Afrikaans University. Online access: 26 April 2008. Available from: http://etd.rau.ac.za/theses/available/etd-08292005-095210/restricted/AComparative.pdf • Whyte A.V, (1995) BUILDING A NEW SOUTH AFRICA: VOLUME 4 Environment, Reconstruction, and Development: A Report from the International Mission on Environmental Policy http://www.idrc.ca/en/ev-82682-201-1-DO_TOPIC.html More Recent Articles
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