It’s a trick question.<\/p>\n
Temperature does not cause ice to melt.<\/p>\n
Temperature is an indication of how much (heat) energy stuff has.\u00a0 Or in every day language how hot the stuff is.<\/p>\n
Most stuff can be in one of at least 3 states, solid, liquid\u00a0 or gas. For water these states are called<\/p>\n
My children learned this when they were about 9 at primary school.<\/p>\n
So if you start with ice and give it heat it warms up – its temperature rises. But when it begins to melt ice stays at the same temperature (melting point).\u00a0 As the ice absorbs energy (heat) it changes state (from ice to water) rather than\u00a0 have a rise in temperature.<\/p>\n
Once the ice has all melted its temperature will rise if it absorbs more heat, until it gets to boiling point when the temperature stays at boiling point as heat is absorbed until the water has changed to gas.<\/p>\n
I started writing about sea level rise a year ago when EA (Environment Agency) wanted to make a hole in the sea wall about 1\/2 mile from where I live.\u00a0 This from the body responsible for flood defense in the UK.<\/p>\n
EA’s argument is<\/p>\n
It proved impossible to have any sensible discussion with EA about the rate of sea level rise, using observations held by www.psmsl.org as EA claimed they were bound to take DEFRA’s projections.<\/p>\n
I have posted about DEFRA 2006 and DEFRA 2009<\/a> projections.\u00a0 Also I have put pages on JeremyShiers.com<\/a> (outside the blog) for every station in UK that www.psmsl.org<\/a> hold data for.<\/p>\n DEFRA obviously didn’t believe their 2006 projections as the 2009 projections were lower.<\/p>\n The 2009 projections came in 3 varieties (high medium and low) and even the low variety was higher than observations.<\/p>\n I guess by now you were expecting some sort of ruse.<\/p>\n Here it is.\u00a0 There was a fourth extra high projection made (called H++ or High++).\u00a0 This H++ scenario was described as “extremely unlikely” but “physically possible given known laws of physics”.<\/p>\n For some reason person leading the team that produced these projections, Jason King, works for the Met Office.<\/p>\n Given the Met Office don’t seem to be able to predict the weather tomorrow – what hope have they got of predicting sea levels 100 years from now.<\/p>\n Anyway what this meant was that EA no longer had to bother talking about why they were using projections that were very different from observed rates of sea level rise.\u00a0 They could simply say<\/p>\n “Yes we know the projections are much higher than observations, but they represent a worst case scenario and we are required by DEFRA (our paymasters) to use the H++ scenario for planning purposes”<\/p>\n This is a bit like saying<\/p>\n “I know my house is extremely unlikely to fall down, but I’m going to knock it down now just in case.”<\/p>\n Read all about the DEFRA climate change projections<\/a>\u00a0 (I recommend checking out what they mean by probability) and even EA Shoreline Management Plan<\/a>.<\/p>\n By December 2011 the local branch of EA had run out of answers to my questions (or just got feed up with them) so they passed me on to Bill Donovan who is<\/p>\n Senior Advisor, Climate Change, Flood and Coastal Risk Management, National Office<\/p>\n Bill sent me several papers including this A Sea Of Uncertainty<\/a> anyway.<\/p>\n Nonetheless A Sea Of Uncertainty<\/em> talks about various possible contributions to sea level rise and concludes that they would add up to less than the expected 2 meters (or 1.9). Then they state this<\/p>\n The semi-empirical methods assume that any difference is due to a missing contribution<\/strong> that will increase with global warming.<\/p>\n Even though it is immediately qualified with this<\/p>\n Though that assumption may be correct, without understanding\/identifying the physical processes that may make up this shortfall in sea level, there is little in the way of supporting evidence.<\/p>\n Still leaves me gobsmacked. And actually\u00a0 Jason, there is NO supporting evidence at all.<\/p>\n People who are paid by UK tax payer are seriously writing papers which talk about “missing contributions” increasing with “global warming”.\u00a0 Why not write<\/p>\n because we don’t get the result we want when we add up all the possible contributions we will assume that there is a magic ingredient which will give us the result we want AND this magic ingredient will get bigger with global warming (whatever that is).<\/p>\n I should say that overall A Sea Of Uncertainty<\/em> says that there is no evidence for sea level rise of the order of 2 meters, strange that offers any support to the idea especially as it says of semi-empirical methods<\/p>\n “The approach is loosely based on an understanding of physical processes, but the relationship is determined by statistical methods. The general assumption is that the relationship between sea level rise and temperature (or forcing) will hold in the future and for a much greater range of warming than occurred during the period from which it was calibrated<\/strong>.”<\/p>\n Obviously whoever developed this model has no idea that this assumption is valid.<\/p>\n The amount of heat stuff absorbs as it warms is called specific heat.<\/p>\n The amount of heat stuff absorbs as it changes state (e.g. melts) is called latent heat.<\/p>\n There are tables of the values for specific and latent heat, especially for common stuff such as water, for example at engineeringtoolbox.com<\/a>.<\/p>\n Wikipedia<\/a> has details of the size of the earth and weight of the atmosphere.<\/p>\n Energy is measured in Joules (symbol j)<\/p>\n Specific heat is the amount of heat need to raise a given weight of stuff by 1\u00b0C.<\/p>\n Latent heat is the amount of heat need to change state of a given weight of stuff.<\/p>\n If you not familiar with it the little 2 in 102<\/sup> just tells you the number of zeroes after the 1, so<\/p>\n As we will have 1023<\/sup>, this saves writing out a lot of zeroes.<\/p>\n Energy required to melt enough ice to raise sea level 2 meters<\/p>\n <\/p>\n For comparison we can look at the weight of the atmosphere and calculate the energy required to raise the temperature 4\u00b0C<\/p>\n <\/p>\n <\/p>\n So roughly 10 times more energy is required to melt enough ice to raise sea levels by 2 meters as to warm just the atmosphere by 4\u00b0 C.<\/p>\n How long would it take to melt this amount of ice?<\/p>\n A simplistic estimate might be if it will take about 100 years to warm atmosphere by 4\u00b0C, then to melt enough ice to raise sea levels by 2 meters will take 1000 years as it requires 10 times as much energy.<\/p>\n Clearly this argument is way too naive.<\/p>\n Even if this amount of energy was available how is the melting going to take place? How will the energy to melt the ice arrive? Presumably by sea.<\/p>\n This implies that water from freshly melted ice will have to move away allowing warmer water to arrive and requiring even more energy.<\/p>\n How long will this take? <\/p>\n And then I put this calculation in an email and sent it to Bill.\u00a0 I’m waiting for a reply.<\/p>\n <\/p>\n It will not be enough to supply 2.41 \u00d7 1023<\/sup> Joules and say ice will melt.\u00a0 What about the rest of the earth; land oceans and atmosphere.\u00a0 The heat will be distributed around the whole world (in some fashion).<\/p>\n So if there is going to be ice melting and global warming there has to be enough energy to<\/p>\n Obviously the second amount of heat is harder to estimate, not least as it depends to what depth the earth and oceans are heated.<\/p>\n Lets look at the Gulf Stream<\/a>, Wikipedia says that it is\u00a0 at least 800 meters deep. This paper\u00a0 \u00a0 Deep-Ocean Heat Uptake inTransient Climate Change<\/a>\u00a0 claims there is equal heat between<\/p>\n Now with the aid of some drastic simplifying assumptions I will attempt to estimate the energy needed over the next century to<\/p>\n Assumptions are<\/p>\nIntroducing Bill Donovan of EA<\/h2>\n
\nIf you look at the references to this paper you can see that they’ve used the old advocates trick of only using references that support their case. Who are<\/p>\n\n
Time For Some School Level Physics<\/h2>\n
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\nTemperatures in the Arctic and Greenland are well below zero for most of the year. This suggests even if there was increased melting during the \u2019summer\u2019 there would be freezing in winter.<\/p>\n
\nWhat will drive the warmer water to Arctic and Greenland?<\/p>\nAnd Then?<\/h2>\n
But there’s more.<\/h2>\n
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