Why do people keep this meme that C/C++ is so insecure? Remember, deep down inside the other languages, there often is a compiler, library, interpreter, etc written in C/C++.
Which is irrelevant. That code can be thoroughly tested and safe, even with the fundamental issues of C++. What matters is your code. You probably won't get the chance to test that code thousands or millions of times the way the compiler/library or interpreter has been.
It's not that C/C++ is so insecure by itself, the problem is that programmers may not have used the best programming practices. There are plenty of libraries for handling strings and memory allocation in C, in C++ there are string and storage classes that do as much or as little checking as you need.
C/C++ IS insecure by itself, because of what it allows you to do. No programmer is perfect, and we all make mistakes. Driving without a safety belt is fundamentally less safe, and you can't argue it away by talking about 'people not driving skillfully enough'.
When you are an expert programmer there are places where you need more efficiency than the super-safe string routines can give you. It's the job of the expert to determine exactly how to balance efficiency against security, and only C/C++ can give you this balance.
I would be very surprised to know exactly when you think this is the case. If it is, it is for the most specialised circumstances. The problem with C/C++ is you have this division between safe (with checks) or fast. Other languages get around this problem, by including safety, but allowing the safety checks to be optimised away by code analysis, often at run time. For example, you could have code something like this:
int [] array = new int [4]; for (int i = 0; i 4; i++) array[i] = i;
The compiler/runtime can analyse this code, and because it is obvious that the bounds of 'array' are never exceeded here, remove any checking and optimise hugely.
It is a myth that you need to balance efficiency against security the C/C++ way.
Kevin Vranes from the University of Colorado at Bolder has this to say
Which simply reveals you have no understanding of or respect for the way science works. On any subject you can find someone who can provide a statement contrary to the mainstream. Science is not about the views of individuals (not even those as respected as Einstein or Newton). What mattered was the large number of researchers who backed up their views.
There are lots of scientists who see unrealistic models, that are fed with incomplete or incorrectly gathered data
Right. I challenge you. Name them, or shut up.
I'll tell you what I am fed up with - and that is the mainstream media perverting things so as to present controversy where there is none, and encouraging the public to believe that anthropogenic climate change is a myth. The time where this dangerous distortion of science can be tolerated is past.
In view of your post, I honestly apologise for my overtly sarcastic tone - I misjudged you.
I fully agree that argument from authority is, of itself, a poor argument. The problem is how to know when an argument from someone who is not an authority is valid? Arguing with scientists is a very good approach, usually because good scientists will argue back in a friendly way.
Climate science is certainly not about certainty, the problem is that the range of probabilities is troubling.
Really? 'Cept 20 years ago the 'experts' were warning about global COOLING. But hey! Whats a lil 'minor' error between 'concerned scientists' right? Global Warming!! Yeah! Now THATS where the MONEY is at! Hurry up! The bandwagon is leaving for its next stop!
Oh for goodness sake, can't you be bothered to even do a little bit of research?
Just to save you some time, yes the experts were warning about global cooling. And do you know why? I shall tell you! It is because of (then) recent data about interglacial periods. They were warning about global cooling on a timescale of millenia, and they were right, but some in the media blew this out of proportion. Sorry, but there was no error, convenient as it may be for your cosy little view of the world. Both the global warming and the global cooling ideas are right, just on different timescales.
How can it be "current" climate science and also a fact? Either way, like it or not, your post was an argument from authority. Feel free to call it an "argument from fact" if it makes you feel better. I know the truth, because leading logicians said it was so.
I am afraid your logic isn't that good.
What is a fact is that current climate science includes an understanding of the changes in solar radiation. It is also a fact that past climate science has also included this understanding.
You can use the term "argument from authority" all you want, but this is not the case. I am not saying that "climate scientists must be take solar radiation into account because they are experts" I am saying that climate scientists do take solar radiation into account because even the most cursory review of climate science publications shows that they have.
But if you prefer your own obscure logic to evidence, I guess that is up to you. If you want to keep arguing this, I would encourage it, as it shows what those who try and deny climate change resort to.
Way to use argument from authority! How indeed can any of us question climate experts? They're EXPERTS for Pete's sake. They've been doing this for years! That'll shut down debate. But if not, don't forget argument from concensus ("Everyone believes it") or if necessary, implied insults ("Only an idiot would question the experts. You're not an *idiot*, are you?")
Where your superb and eloquent attempt to argue back falls down is that what I posted is not an argument from authority, it is an argument from fact. Climate scientists have, of course, known about solar radiation changes, and have been incorporating them into their models and predictions:
"The meeting was devoted to our understanding of the physical processes that connect the Sun's radiation and its variability to our terrestrial environment, including the processes involved with climate and ozone response to solar radiative forcing and the mechanisms that cause solar activity and radiation variations."
I would not say this is a case of an idiot questioning the experts, it a case of someone who is ignorant of current climate science questioning the experts, or at least someone too lazy to do a quick google search which would reveal they are wrong.
And, it is a good rule of thumb that, in general, when some random poster on a forum questions the experts, they are almost always wrong.
When someone can accurately predict what tomorrow's forecast is going to be, then maybe I'll considering listening to what either side has to say.
Hey great! That means you can save on your air-conditioning bills. After all, why should you believe that it is going to get hot in summer - they can't even predict the weather tomorrow.
However, proving that man is the cause is a whole different kettle of fish. Consider the following points - The Sun is the single largest contributor to the Earth's temperature, consequently variation in it's output is a first order effect. Oh -and did you know the Sun HAS changed it's output slightly in recent years?
Really? That is amazing! You had better immediately contact the IPCC and major groups studying and modelling climate change, because you alone have realised that the the sun has changed its output, and they, of course, haven't. Your unique insight into climate change could change everything! I mean, surely these people who have been studying climate (some of them for decades) could never have realised that the output of the sun could change, could they?
Each time the program is run, it would then collect profiling information and an idle-priority thread would recompile it based on this. Once you are in a state where the successive profile and optimisation runs aren't changing the code much, you would just keep this code.
My impression is that this would be a lot of effort for little gain. JVMs already have great performance, and don't take long to optimise code. Furthermore, they can even do this in memory-limited situations (HotSpot will run even for mobile Java). And, as you say, the runtime situation can change. I am willing to have my mind changed, but for now, I just can't see any real advantage.
The safe memory management is an important issue. But there is another advantage of Java which is that the byte code Java is compiled to (at least as an intermediate stage) is pretty compact, which makes it very suitable for low-memory systems.
only people who are not expert in C/C++ claims that java have the same speed. take 1 specialist in C++ and one in java.. tell then to do a program, and see who is the winner.
Not true. I have been using C (and Fortran) since the 70s and C++ since the 80s. I regularly benchmark Java against C++. Java does occasionally come out as the winner.
The only benchmark on the web that says java is fast, is from people who are specialists in java, but is a begginer C++ programmer.
Not true. There have been many benchmarks showing that Java has equivalent to C/C++ speed for many intensive numerical algoriths and test suites (such as Linpack). The people who implement the benchmarks are certainly not C++ beginners.
take programs like azureus, very nice and works well, but eats a lot of memory and cpu. ( 30% of my cpu just to handle a few sockets?! ), hey i can handle 40000 connections in C++ , can you do that in java?
Yes, of course you can. The clustered cacheing product for Java called Coherence can easily handle over 65,500 concurrent connections on a single server. That is close to the theoretical maximum possible.
Java can be compiled by something like gcj or interpreted by a JVM.
Almost all Java on JVMs is now compiled. A better way to put things is that Java can be largely pre-compiled by something like gcj, or compiled at run-time by a JVM.
> If you already cache the native code on disk somewhere (which you really ought to; it's just a waste of cycles to compile it every time you run it)
Give the man a cigar!
He's just discovered the reason compilers were invented in the first place.:)
Firstly, this really isn't a waste of cycles to compile - it is done in a background thread, and only 'hotspot' code is compiled, which is normally a small fraction of the entire app. Concern over the small amount of processing involved is excessive.
Secondly, this is not why compilers where invented. The on-the-fly-with-optimisation compilation approach (not JIT) was only researched in the 90s with the invention of the Self language - it is recent.
It wouldn't be too hard to implement this in a JVM.
There seems to be a persistent view that once-only compiling is a good thing. It is for some apps (when you need very small binaries that start up quickly) but it a large number of cases, it isn't. It is far better to have apps continually profiled and re-optimised as they run - there is a potential for much better performance than the for once-only compiled apps.
But for heavyweight modelling applications, I'm afraid Java's not really in the game; those little limitations/performance penalties for safety just multiply up too fast.
This is yet another old myth. IBM demonstrated long ago that with the right coding, Java could match FORTRAN speeds (with the right VM technology). There are few penalties for safety, as the code analysis performed by the optimising native code translator usually allows array bound checks (for example) to be optimised out. You have to code so as to allow such optimisations to be done, but this is certainly possible.
Java isn't that much slower if you actually take the time to compile it to native code first. Using something like a JIT compiler http://en.wikipedia.org/wiki/Just-in-time_compilat ion can greatly increase the speed of your code and put it close in line with C++.
This is a bit of an old myth. Almost all Java is run as native code these days, even on VMs, and is mostly pretty close to C++ speed. Benchmarks that show Java as significantly slower than C++ usually result from not allowing the VM enough time to perform native code translation of time-critical code. Java has moved away from JIT compilation (as against the later optimisation of HotSpot) because it led to long start-up times - you had to wait for code to be compiled to native before it ran. Now Java usually starts up as interpreted, with the translation to native code happening later on, in the background.
Where C, C++ and D win out over Java in terms of performance is when you need programs that have to start up fast, run fast, but only for short periods (a few seconds).
We had global warming 30 years ago? I thought we were all supposed to fear global cooling back then.
No, we weren't. That was simply media misreporting of recent discoveries of the timings of ice ages.
Seriously, if we had an event of this size a mere thirty years ago, it obviously isn't the one-of-a-kind end-of-the-world-in-twenty-years event the media is portraying it to be. What is the frequency of such events?
That doesn't matter. What matters is the overall frequency of all events which indicate melting. The frequency is high, and increasing. Within my lifetime (if I have a long life) the Artic will be free of ice in summertime. Will you still be doubting global warming even then?
Been there. Done that. That's just Japan, but major quakes have caused severe damage in other parts of the world. Tragic? Yes. Severly damaging to the local economies? Yes. However, to say they had major consequences on the economy of the whole world? No.
Sorry, but that is nonsense. Kobe is not Tokyo.
Correlation is not causatin. Let me say that again; correlation is NOT causation. Would the world climate be changing if mankind was not here? Yes. This is undisputed. So what makes you so sure that mankind is all of a sudden the cause? If we are the cause then without mankind the climate would not change, yet science has demonstrated that the climate has been changing for quite some time, in cycles of heating and cooling long before mankind could possibly have any effect. Is it likely that mankind has some effect on the climate? Sure. But when you state that mankind is the cause you are making far more assumptions than hard science can support.
No, only more assumptions than your assumptions support.
Of course correlation isn't causation. And, of course, climate would be changing if mankind were not here. The issue is how fast things are happening. Climate change is now happening beyond what the normal natural cycles predict.
Here are some established hard scientific facts:
1. CO2 is a greenhouse gas. Increase CO2 concentration and you warm the planet. This is well established, and there is no doubt about it.
2. Mankind is increasing CO2 at a dramatic rate. Mankind is pumping CO2 into the atmosphere at a rate that is way above anything that is happening in Nature - more than decomposition, more than volcanic activity. There is a large turnover of CO2, but the amount we are producing is overwhelming it.
So, for you to be right, either:
1. CO2 has ceased in some way to be a greenhouse gas, or
2. The CO2 mankind has produced is some sort of 'magic' CO2 that has special properties.
Warming of the earth in the recent past is a fact.
True.
"Global Warming," or human initiated carbon emission based climate change, is up for debate contrary to conventional wisdom.
Interesting. So please could you provide some new scientific evidence as to how pumping vast amounts of CO2 into the atmophere, enough to double the concentration in the near future, does not cause global warming? (Sorry, I should have said "Global Warming") If you think this is 'debatable', then presumably you have some new facts about this matter that are not available to the vast majority of scientists? This is your chance to provide them. Perhaps you have some 'unconventional wisdom' about the properties of the CO2 molecule?
Am I failing to see the big picture? Not at all. I just believe the world economy doesn't consist of a few metropolitan centers of which I would guess much less than 10% of the world's population inhabit.
Actually, it does. The consequences to the world economy of, say, an earthquake that devastated Tokyo would be appalling.
Climate Change is real. Saying mankind is the cause, or that it will be our doom is nothing more than fear mongering.
And I think this statement sums up so much about the troubled psychology of so many climate change deniers. Because they worry about doom, they deny that we are causing it.
First, some science. We are causing it. We are pumping vast amounts of greenhouse gas into the atmosphere.
Secondly, no-one is talking about 'doom'. We have been through two world wars in the past century, and climate change is unlikely (at least in the short term) to result in that amount of devastation. However, it will cause serious problems.
Yes, of course I do, otherwise I would not have posted the claim. Here is an example. http://www.agu.org/pubs/crossref/2005/2004GL021387 .shtml "Evidence for subglacial water transport in the West Antarctic Ice Sheet through three-dimensional satellite radar interferometry"
I think the appropriate question here is, given that this is a well-documented and understood phenomenon, what are your political motives for questioning it?
It seems like an unlikely scenario in any case. Water doesn't exactly make a good lubricant for sub-freezing ice, it has terrible viscosity performance below 32F!
That is not the point. It has to do is have better viscocity performance than pure ice.
Puhlease.... It takes more than 20 years for ice this thick to melt to a shelving point.
No, it doesn't. All it takes is for some surface meltwater to percolate down through the ice. Below the ice, it can act as a lubricate, allowing fast movement.
So...even the researchers working on the issue say that they don't know if the cause is 'global warming', whatever that might be defined as, or something else. If the cause is the 'something else' then maybe the same thing happened 30 years ago, too.
No. You are misinterpreting scientific honesty. "Cannot definitively say" does not mean "don't know".
Slashdot Mirror
Why do people keep this meme that C/C++ is so insecure? Remember, deep down inside the other languages, there often is a compiler, library, interpreter, etc written in C/C++.
Which is irrelevant. That code can be thoroughly tested and safe, even with the fundamental issues of C++. What matters is your code. You probably won't get the chance to test that code thousands or millions of times the way the compiler/library or interpreter has been.
It's not that C/C++ is so insecure by itself, the problem is that programmers may not have used the best programming practices. There are plenty of libraries for handling strings and memory allocation in C, in C++ there are string and storage classes that do as much or as little checking as you need.
C/C++ IS insecure by itself, because of what it allows you to do. No programmer is perfect, and we all make mistakes. Driving without a safety belt is fundamentally less safe, and you can't argue it away by talking about 'people not driving skillfully enough'.
When you are an expert programmer there are places where you need more efficiency than the super-safe string routines can give you. It's the job of the expert to determine exactly how to balance efficiency against security, and only C/C++ can give you this balance.
I would be very surprised to know exactly when you think this is the case. If it is, it is for the most specialised circumstances. The problem with C/C++ is you have this division between safe (with checks) or fast. Other languages get around this problem, by including safety, but allowing the safety checks to be optimised away by code analysis, often at run time. For example, you could have code something like this:
int [] array = new int [4];
for (int i = 0; i 4; i++) array[i] = i;
The compiler/runtime can analyse this code, and because it is obvious that the bounds of 'array' are never exceeded here, remove any checking and optimise hugely.
It is a myth that you need to balance efficiency against security the C/C++ way.
Kevin Vranes from the University of Colorado at Bolder has this to say
Which simply reveals you have no understanding of or respect for the way science works. On any subject you can find someone who can provide a statement contrary to the mainstream. Science is not about the views of individuals (not even those as respected as Einstein or Newton). What mattered was the large number of researchers who backed up their views.
There are lots of scientists who see unrealistic models, that are fed with incomplete or incorrectly gathered data
Right. I challenge you. Name them, or shut up.
I'll tell you what I am fed up with - and that is the mainstream media perverting things so as to present controversy where there is none, and encouraging the public to believe that anthropogenic climate change is a myth. The time where this dangerous distortion of science can be tolerated is past.
In view of your post, I honestly apologise for my overtly sarcastic tone - I misjudged you.
I fully agree that argument from authority is, of itself, a poor argument. The problem is how to know when an argument from someone who is not an authority is valid? Arguing with scientists is a very good approach, usually because good scientists will argue back in a friendly way.
Climate science is certainly not about certainty, the problem is that the range of probabilities is troubling.
Anyway, I apologise for a harsh post.
Really?
'Cept 20 years ago the 'experts' were warning about global COOLING.
But hey! Whats a lil 'minor' error between 'concerned scientists' right?
Global Warming!! Yeah! Now THATS where the MONEY is at!
Hurry up! The bandwagon is leaving for its next stop!
Oh for goodness sake, can't you be bothered to even do a little bit of research?
Just to save you some time, yes the experts were warning about global cooling. And do you know why? I shall tell you! It is because of (then) recent data about interglacial periods. They were warning about global cooling on a timescale of millenia, and they were right, but some in the media blew this out of proportion. Sorry, but there was no error, convenient as it may be for your cosy little view of the world. Both the global warming and the global cooling ideas are right, just on different timescales.
How can it be "current" climate science and also a fact? Either way, like it or not, your post was an argument from authority. Feel free to call it an "argument from fact" if it makes you feel better. I know the truth, because leading logicians said it was so.
I am afraid your logic isn't that good.
What is a fact is that current climate science includes an understanding of the changes in solar radiation. It is also a fact that past climate science has also included this understanding.
You can use the term "argument from authority" all you want, but this is not the case. I am not saying that "climate scientists must be take solar radiation into account because they are experts" I am saying that climate scientists do take solar radiation into account because even the most cursory review of climate science publications shows that they have.
But if you prefer your own obscure logic to evidence, I guess that is up to you. If you want to keep arguing this, I would encourage it, as it shows what those who try and deny climate change resort to.
Way to use argument from authority! How indeed can any of us question climate experts? They're EXPERTS for Pete's sake. They've been doing this for years! That'll shut down debate. But if not, don't forget argument from concensus ("Everyone believes it") or if necessary, implied insults ("Only an idiot would question the experts. You're not an *idiot*, are you?")
g .html
Where your superb and eloquent attempt to argue back falls down is that what I posted is not an argument from authority, it is an argument from fact. Climate scientists have, of course, known about solar radiation changes, and have been incorporating them into their models and predictions:
http://lasp.colorado.edu/sorce/Dec03ScienceMeetin
"The meeting was devoted to our understanding of the physical processes that connect the Sun's radiation and its variability to our terrestrial environment, including the processes involved with climate and ozone response to solar radiative forcing and the mechanisms that cause solar activity and radiation variations."
I would not say this is a case of an idiot questioning the experts, it a case of someone who is ignorant of current climate science questioning the experts, or at least someone too lazy to do a quick google search which would reveal they are wrong.
And, it is a good rule of thumb that, in general, when some random poster on a forum questions the experts, they are almost always wrong.
When someone can accurately predict what tomorrow's forecast is going to be, then maybe I'll considering listening to what either side has to say.
Hey great! That means you can save on your air-conditioning bills. After all, why should you believe that it is going to get hot in summer - they can't even predict the weather tomorrow.
However, proving that man is the cause is a whole different kettle of fish. Consider the following points - The Sun is the single largest contributor to the Earth's temperature, consequently variation in it's output is a first order effect. Oh -and did you know the Sun HAS changed it's output slightly in recent years?
Really? That is amazing! You had better immediately contact the IPCC and major groups studying and modelling climate change, because you alone have realised that the the sun has changed its output, and they, of course, haven't. Your unique insight into climate change could change everything! I mean, surely these people who have been studying climate (some of them for decades) could never have realised that the output of the sun could change, could they?
That was sarcasm, by the way.
Each time the program is run, it would then collect profiling information and an idle-priority thread would recompile it based on this. Once you are in a state where the successive profile and optimisation runs aren't changing the code much, you would just keep this code.
My impression is that this would be a lot of effort for little gain. JVMs already have great performance, and don't take long to optimise code. Furthermore, they can even do this in memory-limited situations (HotSpot will run even for mobile Java). And, as you say, the runtime situation can change. I am willing to have my mind changed, but for now, I just can't see any real advantage.
The safe memory management is an important issue. But there is another advantage of Java which is that the byte code Java is compiled to (at least as an intermediate stage) is pretty compact, which makes it very suitable for low-memory systems.
only people who are not expert in C/C++ claims that java have the same speed.
take 1 specialist in C++ and one in java.. tell then to do a program, and see who is the winner.
Not true. I have been using C (and Fortran) since the 70s and C++ since the 80s. I regularly benchmark Java against C++. Java does occasionally come out as the winner.
The only benchmark on the web that says java is fast, is from people who are specialists in java, but is a begginer C++ programmer.
Not true. There have been many benchmarks showing that Java has equivalent to C/C++ speed for many intensive numerical algoriths and test suites (such as Linpack). The people who implement the benchmarks are certainly not C++ beginners.
take programs like azureus, very nice and works well, but eats a lot of memory and cpu. ( 30% of my cpu just to handle a few sockets?! ), hey i can handle 40000 connections in C++ , can you do that in java?
Yes, of course you can. The clustered cacheing product for Java called Coherence can easily handle over 65,500 concurrent connections on a single server. That is close to the theoretical maximum possible.
Java can be compiled by something like gcj or interpreted by a JVM.
Almost all Java on JVMs is now compiled. A better way to put things is that Java can be largely pre-compiled by something like gcj, or compiled at run-time by a JVM.
> If you already cache the native code on disk somewhere (which you really ought to; it's just a waste of cycles to compile it every time you run it)
:)
Give the man a cigar!
He's just discovered the reason compilers were invented in the first place.
Firstly, this really isn't a waste of cycles to compile - it is done in a background thread, and only 'hotspot' code is compiled, which is normally a small fraction of the entire app. Concern over the small amount of processing involved is excessive.
Secondly, this is not why compilers where invented. The on-the-fly-with-optimisation compilation approach (not JIT) was only researched in the 90s with the invention of the Self language - it is recent.
It wouldn't be too hard to implement this in a JVM.
There seems to be a persistent view that once-only compiling is a good thing. It is for some apps (when you need very small binaries that start up quickly) but it a large number of cases, it isn't. It is far better to have apps continually profiled and re-optimised as they run - there is a potential for much better performance than the for once-only compiled apps.
But for heavyweight modelling applications, I'm afraid Java's not really in the game; those little limitations/performance penalties for safety just multiply up too fast.
This is yet another old myth. IBM demonstrated long ago that with the right coding, Java could match FORTRAN speeds (with the right VM technology). There are few penalties for safety, as the code analysis performed by the optimising native code translator usually allows array bound checks (for example) to be optimised out. You have to code so as to allow such optimisations to be done, but this is certainly possible.
I use Java for just such modelling.
Java isn't that much slower if you actually take the time to compile it to native code first. Using something like a JIT compiler http://en.wikipedia.org/wiki/Just-in-time_compilat ion can greatly increase the speed of your code and put it close in line with C++.
This is a bit of an old myth. Almost all Java is run as native code these days, even on VMs, and is mostly pretty close to C++ speed. Benchmarks that show Java as significantly slower than C++ usually result from not allowing the VM enough time to perform native code translation of time-critical code. Java has moved away from JIT compilation (as against the later optimisation of HotSpot) because it led to long start-up times - you had to wait for code to be compiled to native before it ran. Now Java usually starts up as interpreted, with the translation to native code happening later on, in the background.
Where C, C++ and D win out over Java in terms of performance is when you need programs that have to start up fast, run fast, but only for short periods (a few seconds).
We had global warming 30 years ago? I thought we were all supposed to fear global cooling back then.
No, we weren't. That was simply media misreporting of recent discoveries of the timings of ice ages.
Seriously, if we had an event of this size a mere thirty years ago, it obviously isn't the one-of-a-kind end-of-the-world-in-twenty-years event the media is portraying it to be. What is the frequency of such events?
That doesn't matter. What matters is the overall frequency of all events which indicate melting. The frequency is high, and increasing. Within my lifetime (if I have a long life) the Artic will be free of ice in summertime. Will you still be doubting global warming even then?
Been there. Done that. That's just Japan, but major quakes have caused severe damage in other parts of the world. Tragic? Yes. Severly damaging to the local economies? Yes. However, to say they had major consequences on the economy of the whole world? No.
Sorry, but that is nonsense. Kobe is not Tokyo.
Correlation is not causatin. Let me say that again; correlation is NOT causation. Would the world climate be changing if mankind was not here? Yes. This is undisputed. So what makes you so sure that mankind is all of a sudden the cause? If we are the cause then without mankind the climate would not change, yet science has demonstrated that the climate has been changing for quite some time, in cycles of heating and cooling long before mankind could possibly have any effect. Is it likely that mankind has some effect on the climate? Sure. But when you state that mankind is the cause you are making far more assumptions than hard science can support.
No, only more assumptions than your assumptions support.
Of course correlation isn't causation. And, of course, climate would be changing if mankind were not here. The issue is how fast things are happening. Climate change is now happening beyond what the normal natural cycles predict.
Here are some established hard scientific facts:
1. CO2 is a greenhouse gas. Increase CO2 concentration and you warm the planet. This is well established, and there is no doubt about it.
2. Mankind is increasing CO2 at a dramatic rate. Mankind is pumping CO2 into the atmosphere at a rate that is way above anything that is happening in Nature - more than decomposition, more than volcanic activity. There is a large turnover of CO2, but the amount we are producing is overwhelming it.
So, for you to be right, either:
1. CO2 has ceased in some way to be a greenhouse gas, or
2. The CO2 mankind has produced is some sort of 'magic' CO2 that has special properties.
Which of these is true?
Warming of the earth in the recent past is a fact.
True.
"Global Warming," or human initiated carbon emission based climate change, is up for debate contrary to conventional wisdom.
Interesting. So please could you provide some new scientific evidence as to how pumping vast amounts of CO2 into the atmophere, enough to double the concentration in the near future, does not cause global warming? (Sorry, I should have said "Global Warming") If you think this is 'debatable', then presumably you have some new facts about this matter that are not available to the vast majority of scientists? This is your chance to provide them. Perhaps you have some 'unconventional wisdom' about the properties of the CO2 molecule?
Am I failing to see the big picture? Not at all. I just believe the world economy doesn't consist of a few metropolitan centers of which I would guess much less than 10% of the world's population inhabit.
Actually, it does. The consequences to the world economy of, say, an earthquake that devastated Tokyo would be appalling.
Climate Change is real. Saying mankind is the cause, or that it will be our doom is nothing more than fear mongering.
And I think this statement sums up so much about the troubled psychology of so many climate change deniers. Because they worry about doom, they deny that we are causing it.
First, some science. We are causing it. We are pumping vast amounts of greenhouse gas into the atmosphere.
Secondly, no-one is talking about 'doom'. We have been through two world wars in the past century, and climate change is unlikely (at least in the short term) to result in that amount of devastation. However, it will cause serious problems.
And you have evidence for this claim?
7 .shtml
Yes, of course I do, otherwise I would not have posted the claim. Here is an example.
http://www.agu.org/pubs/crossref/2005/2004GL02138
"Evidence for subglacial water transport in the West Antarctic Ice Sheet through three-dimensional satellite radar interferometry"
I think the appropriate question here is, given that this is a well-documented and understood phenomenon, what are your political motives for questioning it?
It seems like an unlikely scenario in any case. Water doesn't exactly make a good lubricant for sub-freezing ice, it has terrible viscosity performance below 32F!
That is not the point. It has to do is have better viscocity performance than pure ice.
Well, London is already experiencing an increasing need to use the Thames Barrier to prevent flooding.
My point is that things are fragile. Just imagine the impact on economics of one of the cities I mentioned was flooded.
While I'm writing up my phd? Oh please god no.
Having done that, you have my sympathies!
I'd be willing to acept that it was if there were proof, but I cannot see how it could be proved on just one event of this type.
But, you see, it isn't just one event of this type. It is thousands of measurements of decreasing ice thickness and spread.
This is why one can't comment without a good literature survey - there is a mountain of evidence to example.
Anyway, good luck with the PhD!
Puhlease.... It takes more than 20 years for ice this thick to melt to a shelving point.
No, it doesn't. All it takes is for some surface meltwater to percolate down through the ice. Below the ice, it can act as a lubricate, allowing fast movement.
So...even the researchers working on the issue say that they don't know if the cause is 'global warming', whatever that might be defined as, or something else. If the cause is the 'something else' then maybe the same thing happened 30 years ago, too.
No. You are misinterpreting scientific honesty. "Cannot definitively say" does not mean "don't know".