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Arctic Sea Ice Watch
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Current sea ice extent Vs average over the last 7 days:
Coming close to the minimum extent now, which I think occurs in early Sept on average if I am not mistaken? However, it remains to be seen how this much ice extent will increase this year as the waters around the Arctic region are extremely warm at the moment, and are likely to remain so during the coming Autumn season.
Edit: Latest SST anomalies from DMI:
Depressing.
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And in relation to this weeks flooding, Peter Thorne, of Maynooth University, director of the Irish Climate Analysis and Research Units has said that these kinds of events are exactly what is predicted in the climate models. Well see many more of these kinds of events in the future as the planet continues to warm.
I know that, though there's not much sign of it happening yet on our local scale, despite 110 years of warming. Not much trend in water vapour or rainfall stats, according to Met Éireann's own data. I would expect to see some sort of a signal in both over the past century, wouldn't you? Unless you have some other record of an increase in heavy rainfall events here that you can share?
You don't see the evidence because you've got your head buried in the sand. Impact attribution of global warming was in the IPCC reports and there are dozens of peer reviewed articles on the subject every year.
One such study is a meta analysis of other studies, published in the Bulletin of the American Meteorological Society , there is an annual report looking at the extreme weather events that happened the previous year and whether there is a climate change impact
Here is part of the abstract of the 2015 report
The full report can be read here, as well as links to the previous 4 reports.
https://www.ametsoc.org/ams/index.cfm/publications/bulletin-of-the-american-meteorological-society-bams/explaining-extreme-events-from-a-climate-perspective/
Head buried in the sand. Fine. You make it all sound so easy and conclusive, yet we're still only talking about probabilities, and many events occur with no human influence, as outlined in the first chapter (below). That's why I continually ask you why every event is automatically attributed to agw before any analysis takes place.The science has now advanced to the point that we can detect the effects of climate change on some events with high confidence (e.g., especially those linked to temperature), although results are necessarily probabilistic and not deterministic.A large number of papers published in this report over the past five years (~35%) did not find any role for climate change on the risk of the event, and we expect to continue receiving and publishing similarly-themed manuscripts in the future.Those graphs show warming and drought accelerating over the 20th century and into the 21st century which is what we expect it to show.
No they don't, they show a flat trend through most of the 20th century followed by an abrupt hockey stick-type turn in the past 20 years. Where's the slowly rising trend from 1900 onwards?Water systems fail when there is drought. The worse the drought, the more they fail. It's baffling that you refuse to acknowledge that a severe drought wasn't at least partially to blame for a lack of water.
Do you expect increased flow from Turkey during the worst drought since instruments began?
What you're basically doing, is blaming the Turkish and the Syrians for the water shortages because they didn't invest enough in their irrigation systems and refusing to acknowledge that climate change also had a role.
Where did I say that? I said that even before the latest drought there was increasing pressure on resources due to increasing population and the poor system and reduced flows. This is mentioned in the article. Of course a drought makes this worse, but you dismissed these points as "whataboutery" and not significant.0 -
There is a trendGaoth Laidir wrote: »I know that, though there's not much sign of it happening yet on our local scale, despite 110 years of warming. Not much trend in water vapour or rainfall stats, according to Met reann's own data. I would expect to see some sort of a signal in both over the past century, wouldn't you? Unless you have some other record of an increase in heavy rainfall events here that you can share?
This graph is from the same page you got your links from.
And this is what Met Eireann have to say based on the data
Rainfall shows great year to year variability. A 30 year running mean of the national annual rainfall indicated an increase in average national rainfall of approximately 70mm over the last two decades.
As with the annual totals of rainfall, all seasons show a small increase in totals over the last few decades.
https://www.met.ie/climate-ireland/rainfall.asp
Your interpretation of the data, that there isn't a trend, is different from Met Eireann's interpretation of the Data.
It takes decades to establish for certain that a long term trend is there, and not just a statistical outlier, but if we wait for the trend to establish itself to the satisfaction of everyone, it will already be way too late to do anything about it. This is why we need to put our trust in the models and the predictions of these well established models.
Head buried in the sand because there are mountains of evidence showing current impacts of climate change but you don't accept them because scientists speak like scientists and use P values instead of more emotive language (even though it might be warranted given the stakes)Head buried in the sand. Fine. You make it all sound so easy and conclusive, yet we're still only talking about probabilities, and many events occur with no human influence, as outlined in the first chapter (below). That's why I continually ask you why every event is automatically attributed to agw before any analysis takes place.
And because even if these individual events are natural disasters that would have happened anyway, given that the climate models are warning that these kinds of events will happen more often and be more intense we should take them as a kick up the arse while they're still considered extreme and not the new normal. When these events are normal, imagine what the new extreme events will look like?
You must be looking at different graphs to me. The rainfall graph starts off mostly above the average, then moves to about half above average, half below average, and ends mostly below average. That's a fairly consistent trend downwards. (I have to use my own judgement because the graph doesn't plot any rolling average for the whole series)No they don't, they show a flat trend through most of the 20th century followed by an abrupt hockey stick-type turn in the past 20 years. Where's the slowly rising trend from 1900 onwards?
The temperature graph is clearly trending upwards for the whole time series, and the PDSI graph, which is the most useful of the 3, is blatantly curving downwards. (It's a drought severity index that only looks at rainfall and evaporation, so even if rainfall is the same, when temperature goes up, drought increases as the rain evaporates faster, when rainfall decreases along with temperature increasing, we get big changes in the drought severity index)
This whole Syria debate is because you wanted me to show an example of climate change being a threat multiplier, and it turns out you agreed with me all along.Where did I say that? I said that even before the latest drought there was increasing pressure on resources due to increasing population and the poor system and reduced flows. This is mentioned in the article. Of course a drought makes this worse, but you dismissed these points as "whataboutery" and not significant.
The drought made the pressures on population worse, which in turn exacerbated the Syrian civil war.
Do you get what I've been saying yet?
Now guess what's going to happen to regions that rely on glacial melt water when those glaciers are gone due to climate change. Will the wars in these regions have political dimensions? Yes, will the lack of water and mass displacement of people be a major problem that might cause tensions to spill over into civil war? Probably. Will the influx of refugees cause political crises in neighbouring countries? We're seeing that happen in Europe today, why would China and India etc be any different?0 -
There is a trend
This graph is from the same page you got your links from.
And this is what Met Eireann have to say based on the data
Rainfall shows great year to year variability. A 30 year running mean of the national annual rainfall indicated an increase in average national rainfall of approximately 70mm over the last two decades.
As with the annual totals of rainfall, all seasons show a small increase in totals over the last few decades.
Your interpretation of the data, that there isn't a trend, is different from Met Eireann's interpretation of the Data.
It sure is. I fail to see which seasons show an increase, other than summer. If anything autymn, winter and spring show a decrease. I'm not sure how they got the 70-mm annual increase from that data, but even so, it relates to less than a 0.6% increase, and I'm still waiting to see evidence that it was made up from increased flash flood events.It takes decades to establish for certain that a long term trend is there, and not just a statistical outlier, but if we wait for the trend to establish itself to the satisfaction of everyone, it will already be way too late to do anything about it. This is why we need to put our trust in the models and the predictions of these well established models.
But wait, you said there IS a trend. Now you're saying we won't know for decades? Which is it?Head buried in the sand because there are mountains of evidence showing current impacts of climate change but you don't accept them because scientists speak like scientists and use P values instead of more emotive language (even though it might be warranted given the stakes).
Don't worry, you speak enough emotive hyperbole for everyone!
And because even if these individual events are natural disasters that would have happened anyway, given that the climate models are warning that these kinds of events will happen more often and be more intense we should take them as a kick up the arse while they're still considered extreme and not the new normal. When these events are normal, imagine what the new extreme events will look like?
Or we should reduce the impacts of current events by not building on flood planes, by dredging rivers, increasing natural soakage and reducing artificial runoff.
We need to get away from fossil fuels because if we don't we will run into an energy crisis far more serious than any future climate change scenarios.You must be looking at different graphs to me. The rainfall graph starts off mostly above the average, then moves to about half above average, half below average, and ends mostly below average. That's a fairly consistent trend downwards. (I have to use my own judgement because the graph doesn't plot any rolling average for the whole series)
The temperature graph is clearly trending upwards for the whole time series, and the PDSI graph, which is the most useful of the 3, is blatantly curving downwards. (It's a drought severity index that only looks at rainfall and evaporation, so even if rainfall is the same, when temperature goes up, drought increases as the rain evaporates faster, when rainfall decreases along with temperature increasing, we get big changes in the drought severity index).
Blatantly downward? As I said earlier, where is the trend before the past 2 decades? To help you see it I've removed both ends to show 1930-2000. Now, where are these blatant trends you speak of? Rainfall and PDSI falling? Nope. I see no response in either to the temperature trend. As I said, the past 2 decades show an abrupt change, but why not the early century warming or since 1970?
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Maybe you've discovered an error made by Met Eireann in their analysis of their data, you should contact them to let them know.Gaoth Laidir wrote: »It sure is. I fail to see which seasons show an increase, other than summer. If anything autymn, winter and spring show a decrease. I'm not sure how they got the 70-mm annual increase from that data, but even so, it relates to less than a 0.6% increase, and I'm still waiting to see evidence that it was made up from increased flash flood events.
Or maybe you're reading the data wrong. They all show an increase over the 30 years. The average rainfall at the beginning of the 30 years was lower than the average rainfall at the end of the graph for all 4 seasons. And the green line is the average of all years in that 30 year period.
Remember earlier in our discussion when I said I didn't think I am qualified to assess raw data in published peer reviewed papers, so I trust the conclusions of the experts, and you insist that you never believe anything unless you check the data yourself. Well, please consider the fact that you can read these simple graphs with plotted trend lines showing a 30 year average being lower at the start than the end and conclude that the rainfall isn't increasing, and re-evaluate if you are qualified to make a judgement on these papers that contradict what the vast majority of trained experts in their field conclude
There is a trend upwards over the past at least the past 2 decades, but it will take decades to show whether that trend continues, or of it reverts back to the 20th century mean. The models suggest that the trend will continueBut wait, you said there IS a trend. Now you're saying we won't know for decades? Which is it?
Emotive, perhaps, but given the danger, I don't know if it's hyperbole.Don't worry, you speak enough emotive hyperbole for everyone!
Take this abstract from a recent paper called 'Nonlinear climate sensitivity and its implications for future greenhouse warming'
This is Science speak for 'Holy Sh1t, we're screwed!"Global mean surface temperatures are rising in response to anthropogenic greenhouse gas emissions. The magnitude of this warming at equilibrium for a given radiative forcing—referred to as specific equilibrium climate sensitivity (S)—is still subject to uncertainties. We estimate global mean temperature variations and S using a 784,000-year-long field reconstruction of sea surface temperatures and a transient paleoclimate model simulation. Our results reveal that S is strongly dependent on the climate background state, with significantly larger values attained during warm phases. Using the Representative Concentration Pathway 8.5 for future greenhouse radiative forcing, we find that the range of paleo-based estimates of Earth’s future warming by 2100 CE overlaps with the upper range of climate simulations conducted as part of the Coupled Model Intercomparison Project Phase 5 (CMIP5). Furthermore, we find that within the 21st century, global mean temperatures will very likely exceed maximum levels reconstructed for the last 784,000 years. On the basis of temperature data from eight glacial cycles, our results provide an independent validation of the magnitude of current CMIP5 warming projections.
It says that the warmer the climate gets, it becomes much more sensitive to greenhouse gasses, (which makes sense when we consider that the atmosphere holds more water vapour (a significant greenhouse gas), and the oceans can hold less CO2) so if we don't stop global warming early, we're gonna see temperature rises in accordance with the most pessimistic forecasts and catastrophic effects of global warming within the lifetimes of many people alive today.
It is a genuine emergency.
We need to do these things too. And these are more urgent in a world where these kinds of events happen more frequently.Or we should reduce the impacts of current events by not building on flood planes, by dredging rivers, increasing natural soakage and reducing artificial runoff.
The energy crisis is that we have too much oil, not that we don't have enough. There are 50 years of proven oil reserves left at the rate we currently burn it. On top of that, there is another trillion barrels of shale oil (low estimate) that would become viable to produce long before we have a major energy crisis and by then we'll have already have caused runaway global warming and the eventual collapse of civilisation as we know it. We need to move to renewable energy ASAP and we need to commit to leave most of the Oil Coal and Gas in the ground.We need to get away from fossil fuels because if we don't we will run into an energy crisis far more serious than any future climate change scenarios.
Come back to me when you've plotted the graph correctly showing the rolling 30 year trend for the series rather than just removing the bits of the graph that clearly show there is a long term trend and focusing on a bit that is ambiguous.Blatantly downward? As I said earlier, where is the trend before the past 2 decades? To help you see it I've removed both ends to show 1930-2000. Now, where are these blatant trends you speak of? Rainfall and PDSI falling? Nope. I see no response in either to the temperature trend. As I said, the past 2 decades show an abrupt change, but why not the early century warming or since 1970?
If you want to show early century warming, why did you remove the early century data from the graph. There might have been a flat period in the mid century (explainable by natural variability and the global dimming effect as industrial pollution reduced solar radiation reaching the surface) but the 100 year trend is for reduced rainfall, increased temperatures, and increased risk of drought. The past 30 years have seen dramatic increases in warming due to both global brightening (reduction of global dimming as we clean up our air quality) and global warming due to greenhouse gasses (the dominant effect as per the overwhelming consensus of scientists in the field)0 -
Maybe you've discovered an error made by Met Eireann in their analysis of their data, you should contact them to let them know.
Or maybe you're reading the data wrong. They all show an increase over the 30 years. The average rainfall at the beginning of the 30 years was lower than the average rainfall at the end of the graph for all 4 seasons. And the green line is the average of all years in that 30 year period.
Apologies, I was indeed reading it incorrectly. Got the two averages mixed up! Still, by how much have flash flood episodes increased?Emotive, perhaps, but given the danger, I don't know if it's hyperbole.
Take this abstract from a recent paper called 'Nonlinear climate sensitivity and its implications for future greenhouse warming'
This is Science speak for 'Holy Sh1t, we're screwed!"
It says that the warmer the climate gets, it becomes much more sensitive to greenhouse gasses, (which makes sense when we consider that the atmosphere holds more water vapour (a significant greenhouse gas), and the oceans can hold less CO2) so if we don't stop global warming early, we're gonna see temperature rises in accordance with the most pessimistic forecasts and catastrophic effects of global warming within the lifetimes of many people alive today.
It is a genuine emergency.
That is based on RPC 8.5, which is worst case scenario and on current observations nowhere near where we're heading. We're currently barely even keeping up with the RPC 4.5 projections, as I've shown previously:
We need to do these things too. And these are more urgent in a world where these kinds of events happen more frequently.
The energy crisis is that we have too much oil, not that we don't have enough. There are 50 years of proven oil reserves left at the rate we currently burn it. On top of that, there is another trillion barrels of shale oil (low estimate) that would become viable to produce long before we have a major energy crisis and by then we'll have already have caused runaway global warming and the eventual collapse of civilisation as we know it. We need to move to renewable energy ASAP and we need to commit to leave most of the Oil Coal and Gas in the ground.
Please, quit the Daily Express-esque hyperbole. Civilisation will not end.Come back to me when you've plotted the graph correctly showing the rolling 30 year trend for the series rather than just removing the bits of the graph that clearly show there is a long term trend and focusing on a bit that is ambiguous.
If you want to show early century warming, why did you remove the early century data from the graph. There might have been a flat period in the mid century (explainable by natural variability and the global dimming effect as industrial pollution reduced solar radiation reaching the surface) but the 100 year trend is for reduced rainfall, increased temperatures, and increased risk of drought. The past 30 years have seen dramatic increases in warming due to both global brightening (reduction of global dimming as we clean up our air quality) and global warming due to greenhouse gasses (the dominant effect as per the overwhelming consensus of scientists in the field)
I left out the grey shaded timeline as the authors said it was an unreliable era due to poor coverage. Nevertheless, here it is included, for what it's worth, showing no drop in rainfall pre-1930 or indeed for the whole century. The only drop has been the past 20 years, which is included in the red trendline.
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July sea ice volume bucked the trend and caused surprises
http://neven1.typepad.com/blog/2017/08/piomas-august-2017.htmlLast month I expected the trend line on the PIOMAS sea ice volume anomaly graph to leave the two standard deviation territory, but I was mistaken, as it has gone up instead of down:
Last year I was of the opinion that the Arctic (and thus the rest of the world) had dodged a bullet, thanks to a slow start of the melting season. This year I'd say it has dodged a cannonball given the record low maximum and the record low volume (by a large margin) for months on end. Not only was there a slow start in May, but also, when the sun started to make itself felt, a larger amount of winter snow on the ice seemed to block the formation of melt ponds. This meant that there's a lot less melting momentum than we saw in years like 2007, 2010 and 2012, which basically can make a big difference for thin ice right behind the periphery.
And right now cyclones still dominate the Arctic. They're quite benevolent, not as destructive as the Great Arctic Cyclones of 2012 and 2016 by far, but more like the persistent cyclones of 2013. The current weather forecast doesn't show much signs of this changing, and so it will be interesting to see whether 2017 is still in second place at the end of this month, or whether it will be overtaken by 2011 and possibly even 2016.
We'll know more in a couple of weeks.
Almost three weeks have passed since that was written and the ice extent continues to flatten out well above 2012. It will be interesting to see where this year finishes.
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There isn't really good data for the statistics on Flash floods that I can find. It's difficult to attribute the causes of flooding when there are so many other factors, such as development, tides and land use that are factors in whether rivers burst their banks.Gaoth Laidir wrote: »Apologies, I was indeed reading it incorrectly. Got the two averages mixed up! Still, by how much have flash flood episodes increased?
But again, I'll retreat to the models. When models are controlled for other variables, there are more intense floods when climate change is factored in compared to atmospheric GHGs at pre-industrial levels.That is based on RPC 8.5, which is worst case scenario and on current observations nowhere near where we're heading. We're currently barely even keeping up with the RPC 4.5 projections, as I've shown previously:
RCP 8.5 refers to the radiative forcing that will happen if we don't reduce our emissions rapidly. The RCP calculations are based on the physics of how
much GHGs will affect the amount of energy the earth traps rather than radiates out into space due to the greenhouse effect. Climate sensitivity relates to how much temperatures will change as a result of changes in greenhouse emissions (sensitivity includes both positive and negative feedbacks like energy absorbed in the oceans and the melting of ice and effects on the biosphere)
Currently we are on the RCP 8.5 path. In order to be on the less dangerous paths, we should have been reducing our greenhouse emissions years ago
This particular study modeled climate going back through 6 glacial cycles, and they discovered that climate sensitivity is higher when temperatures are higher. So as we warm the planet, sensitivity increases in a non linear manner. So that even if it seems like climate sensitivity today is overstated, as temperatures increase, the sensitivity to these GHGs also increase to the point were we are likely to meet or even exceed the temperature increases predicted in the IPCC RCP 8.5 scenario.
(sorry, I thought I had included a link to the study in the last post, but here it is
http://advances.sciencemag.org/content/2/11/e1501923.full
)
The UK independent had this to say in November last yearPlease, quit the Daily Express-esque hyperbole. Civilisation will not end.
"Climate change may be escalating so fast it could be 'game over', scientists warn" which included the following quotes
“It sounds on the apocalyptic side of bad and, in some ways, it is realistic because ‘business as usual’ just got more likely as Trump wants to rebuild the pipelines … the complete ‘fossilisation’ of the US,” he said.
“It was game over at six [degrees] to be honest. I don’t think there was much more to add, other than turning the planet into Venus.”
http://www.independent.co.uk/news/science/climate-change-game-over-global-warming-climate-sensitivity-seven-degrees-a7407881.html
We'll have to agree to disagree there, without the rolling 30 year average plotted on the graph, it's a judgement call, but i still think these graphs show that the temperature and rainfall has been consistent with AGW throughout the whole 20th century.I left out the grey shaded timeline as the authors said it was an unreliable era due to poor coverage. Nevertheless, here it is included, for what it's worth, showing no drop in rainfall pre-1930 or indeed for the whole century. The only drop has been the past 20 years, which is included in the red trendline.0 -
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Nearing the Arctic minimum date now and the recovery this year has been notable. Extent, and volume and thickness will finish well back above 2012, 2015 and 2016.
http://neven1.typepad.com/blog/2017/09/piomas-september-2017.html#more
It seems my prayers from May have been heard:There's nothing else to do but hope that PIOMAS has it completely wrong, or else pray for lots of cold and cloudy weather in the Arctic this summer.Well, the weather did its thing and produced one of the biggest turnarounds
in the Arctic I have seen so far. I mean, in 2013 the ice managed to return from the brink of death, so to say, but at least the winter preceding it had been very cold. This year the melting season started with a record low volume after an incredibly mild winter.
One consequence of that mild winter, however, was lots of snowfall on the ice and adjacent land masses (see here). This snow likely managed to reflect some of the sunny weather that creates what I call melting momentum during May
and June. So, with snow melting out late and not much melting momentum to speak of (yet again), it all came down to what kind of weather we'd be seeing during July and August. Cue low pressure.
Also, the Greenland ice mass may show the first increase this century.
https://nsidc.org/greenland-today/2017/09/late-summer-melting-spike/Extensive and persistent melt in northern Greenland characterized late July to early August. A brief high pressure pattern entered on the west coast led to similar conditions that made 2015 a record melt year for the ice sheet’s northern sections. Overall, however, reduced melting and heavy early springtime snowfall may result in a net increase in Greenland’s ice mass this year for the first time this century.
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