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Monthly Archives: June 2008
5 Green Questions (Hanging In The Air)
5 green questions, answered as accurately as I know how:
Question 1: Global warming isn’t real is it? I mean we keep reading reports that the planet hasn’t warmed up at all since 1999. Some say it’s cooling down and so on. It’s all a big hoax.
Answer: Scientifically speaking the planet doesn’t really have an “agreed average temperature”. However there are satellite readings, balloon readings and local temperature readings that do not support the assertion that “the average temperature of the planet is on the increase”, and there are even some that suggest the temperature might be cooling. However, let’s try to provide some perspective as to what this means:
- The problem here is the focus on the word “warming”, which is misleading. Let’s consider the oceans as a single unit. Think of a glass of water on which a large piece of ice is floating. Do you expect the temperature of the surface of the water to increase, while there’s a big ice cube floating around? Not much perhaps (actually, in the Arctic, an increasing temperature of sea water has been observed since 1995, and recently in the region just north of the Chakchi Sea, waters have been 5° C above average.) The global average surface temperature may not increase. Nevertheless, notice that the ice sheet is shrinking dramatically. That means the ocean is absorbing a very large amount of heat, irrespective of the local temperature readings.
- We see the same, but a lesser effect, on land. The permafrost is melting, the glaciers are melting and the snow line on mountains is receding. Heat is being absorbed. There’s also the effect that, where the atmospheric temperature increases, more water evapourates and that takes heat out of the atmosphere.
- So the truth is that the planet is measurably absorbing a great deal more heat that it has been doing. This has changed the local climate in many places and the cause is green house gases.
Question 2: But you can’t ascribe these climate changes to human activity, can you? The earth goes through cycles where the temperature rises and then it falls back down again, doesn’t it? Isn’t what’s happening now just the natural order of things?
Answer: The scientific evidence suggests that there’s a roughly 100,000 year cycle of warming and cooling (much of the evidence has been gathered by the analysis of ice cores). The suggested and believable cause of this is that the earth’s orbit oscillates from more circular to more elliptical (the Milankovitch theory). When the orbit is more circular the Earth heats up, the sea level slowly rises and the level of carbon dioxide in the atmosphere increases. Right now we’re coming to the end of a period of rising temperature and sea level. The actual level of carbon dioxide is about 30% higher at these temperature peaks.
Question 3: But of those measurements, the carbon dioxide level is lagging, isn’t it. The carbon dioxide is the effect rather than the cause of the warming, isn’t it?
Answer: There you go, interrupting before I’ve completed the previous question. Never mind, let’s put the two questions together. The phenomenon of green house gases is real. The main green house gas is carbon dioxide, but also there’s methane and water vapor. Shortwave radiation from the sun hits the earth and (depending on what it hits) some of it is reflected back into the atmosphere as long wave radiation. The green house gases absorb long wave radiation, trapping it in the same way that green house glass traps it. Every time you test a green house gas to see if it does this, it just does it. It never takes a day off.
Estimates suggest that the average global temperature of the Earth would be about -18° C if it weren’t for green house gases (rather than about 15° C). So there seems to be an amplification effect in operation. CO2 is both an effect and a cause of global warming. As the Earth heats up, you get more green house gases, which amplify the temperature rise until it reaches a peak. Currently the global average concentration of carbon dioxide is 387 parts per million and this is rising by an average of 2 ppm per year. This annual rise is attributable primarily to the 6.3 billion tons of carbon dioxide that human beings release into the atmosphere each year.
Question 4. But the whole process will turn around and stop, just like it did over the past 100,000 year cycles, won’t it?
Answer. Unfortunately no-one knows if it will turn round this time, because this cycle is not the same as the previous cycles. This time we have human beings adding billions of extra tons of carbon dioxide and we have no idea whether the cycle will revert in the way that it did before. The worrying difference is that, according to the evidence, atmospheric carbon dioxide is now higher than it’s ever been in the past 500,000 years. The previous high was about 300 ppm, over 300,000 years ago. It’s now above 380 and rising at 2ppm each year. So, it is likely that the sea level rise and eventual temperature rise will be higher than before.
The Earth is too complex an ecosystem to model accurately. We are in new territory. Nobody knows whether there is a corrective mechanism that will kick in at some point.
Question 5. So we get a little more ice melt and a bit of coastline change, but otherwise what’s the big deal?
Answer. If only it were so. There is an attendant problem caused by the fact that the sea absorbs carbon dioxide. About half of the billions of tons of carbon dioxide we add to the atmosphere get absorbed by the sea. In some ways it’s a useful mechanism because it reduces the green house effect. Unfortunately it raises the Ph level of the sea. What’s happening is that the sea is becoming more and more acidic, as more carbon dioxide is absorbed.
Look at all the coastline of most countries in the world and what you see are sandy beaches. Those sandy beaches are formed from the shells of trillions and trillions of shellfish that have been crumbled up by the waves over millions of years. Well that particular process may come to a full stop. Here’s why:
If the sea continues to absorb carbon dioxide at the current rate then by 2075 all coral reefs will start to die, or have died. (We probably can’t stop this).
By 2300 the sea will be too acidic for shellfish to form shells.
It’s hard to believe, I know, but that’s what the scientific evidence is suggesting. If you want a detailed analysis get hold of the full article called The Darkening Seas from the New Yorker.
What would it mean if there were no shellfish?
Click here for all postings on Global Warming.
Posted in Campaigns
Tagged Ecology, Global Warming, main green house gas;, Subject, the New Yorker;
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The Paradox of Mistaken Identity
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The Paradox of Mistaken Identity (from the series: Photosyntheticism)
She never once questioned who she was until she attended a Masqued Ball, held in some old manor house in rural Sussex. She felt a little uneasy that day in the fancy dress place, when she tried on various costumes and Venetian masques. It felt as though she was standing on a theatre stage in front of an empty auditorium. She chose her costume and she believes she chose well – for when she put the costume on to go to the ball, she felt as though she were stepping into someone else’s clothes.
She never donned her Venetian masque until she stopped her car outside the old manor house – but when she did, the transformation was complete. As the sun slowly set and she walked up the driveway to the door, she left one world and entered into another. The doorman smiled, then bowed and opened the large oak doors for her. There was already a throng of guests milling around under the chandeliers and waltz music drifted on the air from the ballroom. She felt relieved that she had not arrived too early.
“It was the strangest of things,” she said, “nobody recognized me, and yet everyone knew who I was. I had been living my life in the shadow of a mistaken identity, and suddenly this shadow was lifted and cast aside. Even now, I cannot say that I discovered who I was, but at last I knew for certain who I was not.”
“At midnight the music stopped, there was silence, and we all took off our masques”
She glanced at once into the mirror, but she did not recognize the person that stared back at her.
8 Disruptive Technology Changes
From a technology perspective, we are in the most disruptive phase of Information Technology since the computer was born. It might not seem that way, but if you list the disruptive technologies currently in play, it paints an intriguing picture. So here’s a list:
1. Multicore Chips
Multicore chips have been around for a year or two. They were introduced as Moore’s Law ran out of steam. Each core is a distinct cpu and thus it is possible on PCs and laptops to simply split the workload in two and harness both cpus reasonably efficiently. However as you increase the number of cores on a chip, this strategy starts to fail and you need to specifically program for multiple cores using programming languages and models designed for the job. (A UK parallel programming consultancy, Concertant does an annual survey on multicore. If you’re interested in completing this, here’s the survey link.)
There has been talk of chips with hundreds of cores and, if general purpose uses can be found for them, they will likely be introduced in the coming 5 years or so. Multicore favors virtualization, so there is little doubt that multicore will persist both on the server and on the client at least up to 8 cores. However, the destiny of multicore may also be tied to the GPU.
2. The GPU Absorbs the CPU
This strongly relates to the previous multicore disruption. Nvidia believes that the GPU (Graphics Processing Unit) will absorb the CPU in the coming years. Clearly, that would rain on Intel’s parade in no uncertain terms, and of course, the sun would shine like a diamond on Nvidia’s parade. Nvidia has a point though. As interfaces increase in sophistication it’s the GPU that does most of the work, the CPU having topped out quite a while ago. As far as I can see there’s no reason not to put a few x86 core onto a GPU and make the CPU disappear, as in a magic trick. For further details read What is a GPU and Why is it Important?
3. Memory Replacing Disk
I wrote about this in detail quite a while ago here. The point is that flash memory, which is non-volatile and provides much faster access than disk, is gradually replacing disk. Samsung’s recently announced 256GB solid state drive (SSD) is 2.4 times faster than disk. That doesn’t sound too revolutionary, but the point is that nearly all the business applications we run assume that we are pulling data from a spinning disk and soon that will not be the case. Hence there will likely be an opportunity to rethink database at the physical level.
4. The Network Infrastructure Absorbs the Servers
Recently introduced all-singing-all-dancing network switch products can deliver astonishing network speeds – in the terabyte per second area. For full details see The Server Vendors v Cisco: Is This A New Technology War? and Brocade: The Heart and Lungs of the Network. Note that this bandwidth is greater than the bandwidth between memory and the cpu on a server board. (If you are going to get this fact in perspective, you need to understand that the distance between memory and CPU is very small, so the latency of a single instruction is lower memory-to-cpu than over the network, but the network bandwidth is higher because it embodies huge parallelism on fiber). The point is that with networks this capable it is feasible to have an architecture that sends instructions and data anywhere to execute. It diminishes the need to keep the processing close to the data. The ultimate consequence from this is that if you want to manage workloads on a network, you need to do it from the network infrastructure, which, naturally, has an operating system of its own. This will inevitably happen in time.
5. The Network Becomes Real-Time (or near-as-dammit-realtime)
Communications has been converging with computing forever, but only recently have they met and shook hands. The upshot is that IP Addresses becomes the physical communications addresses, Unified Communications rule (see What Is Unified Communications?) and Presence becomes important (see What is Presence and Why Should I Care?.) You should be able to get an immediate understanding of how computer networks become realtime simply by looking at the diagram on this posting and asking yourself whether it needs 99.999% uptime (yes it does).
6. The Network Gets A Management Circuit
A recent, almost silent, trend has seen the installing of Service Processors in servers to improve up-time and provide a circuit by which a network can be better managed. The story is told in greater detail in What is a Service Processor? And Why Should I Care?
7. Virtualization: Everything goes Virtual
I’ve written about virtualization extensively. You can find a page full of Virtualization links here. You could say that it all began with the advent of SANs, which eventually created a common storage pool which you could think of as a “virtualized storage resource.” With the advent of multicore, virtualization just made more and more sense, and it now looks to be the fundamental pattern of how processing resource is allocated and workloads are managed. Naturally the desktop gets pulled in to the virtualization whirlpool and as time passes, we end up with a “common resource space” with end-devices providing access.
8. Cloud Computing
Finally we have cloud computing where pretty much every resource and capability, hard or soft, is provided as a service. For a full description read Everything as a Service: The Growth of Cloud Computing
Anything else?
I could add that everything mentioned so far (hard or soft) could feasibly be addressed using a single 64 bit addressing scheme. That would be game changing, given that we live in an age of 64 bit computing that doesn’t yet exploit 64 bit addressing.
I could also mention that graphene is very likely to replace silicon in chips in the coming 5-10 years, which means that Moore’s Law would get a new lease of life and that the heating problems in data centers would evaporate. (See Graphene: The New Silicon
The point of summarizing all of this, by the way, is to provide a global perspective on the blistering pace of change. If you have anything else you think should be included, please post comments.