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Post by glennkoks on Sept 18, 2011 3:32:59 GMT
Much has been written about how warm the MWP was and how cold the LIA was but what about the roughly 300 years that separates the two climate regimens? I don't think that anyone can argue that the warm period we are currently in is at least as warm as the MWP if not warmer.
What if the same or similar natural conditions prevail and we dip into another colder cycle similar to what we experienced during the LIA? This is not an AGW thread but considering our current warmth what can we expect from the transition?
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Post by trbixler on Sept 18, 2011 4:31:54 GMT
In England Vine street was aptly named. We have not seen a return to that warmth. We know the Thames froze over and had ice Fairs, we might indeed go to that level and hopefully not lower. Ask Sig on his take for food production if indeed it does get colder. Certainly the adaptation to cold will occur but I think adaptation to a little warmer is far easier.
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mien
New Member
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Post by mien on Sept 18, 2011 12:05:07 GMT
Looking through the data it seems more like the change was very abrupt rather then going smoothly through a 300 year period.
1540 was the warmest summer in Europe in thousand years(2003 was nothing in comparison). However the years fellowing to this subtropical summer show a very quick decline in temperatures. In 1564/1565 was one of the coldest winters in history. Also it was during this 1550-1650 period most of the famous 'winter paintings' were made.
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Post by glennkoks on Sept 18, 2011 13:35:51 GMT
mien, temperature reconstructions of the MWP show that it peaked around 1000 - 1200 and the LIA started by 1250 and came on in stages. By around 1300 the summer growing season became very undependable in Europe and led to a serious of famines.
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Post by steve on Sept 18, 2011 13:47:24 GMT
As sigurdur pointed out, data from clam shells plus anecdotal data about famines shows that Iceland's coldest period was not the LIA but the 11th century - a time when parts of Greenland were apparently warmer. So it is certainly clear that local changes in climate can occur to make some places warmer and others colder over a good deal of time.
It's somewhat simple-minded to say adaptation to warm is easier than adaptation to cold. Abrupt climate change in any direction can disrupt food supplies and bring new and different challenges.
A hot summer in the UK will melt roads, damage train tracks and put the electricity supply under pressure for example. And most of us here do not have air conditioning.
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Post by sigurdur on Sept 18, 2011 14:54:51 GMT
glenn:
We are in a transition climate wise, there is no question about this at all. The transition is one from a period of steadily increaseing warmth, to a period of cooling, with warmth interjected at times.
You all know that I am a farmer. My grandparents were farmers. You all know I live in North DAkota, USA. The latitude of where I live is the "breaking" point of change in one direction or the other.
I have shown on this site that North Dakota, as far as temperature, has actually been quit flat on a century scale of time, using the 100 mean value. This is fact.
What we observe here is the change in the abruptness of the change of seasons. Since 2000, our winters have been colder, and somewhat longer. When summer finally shows up, it shows up in a week, whereas 30 years till about 10 years ago it slowly evolved. Not anymore.
When spring hits, it is nearly summer. When winter hits, it is nearly fall.
The early frost, of which I posted a link in the crops topic, shows the devistation to food producers. The cold wet springs as of late have delayed planting, and the generally earlier hard freezes have resulted in damage.
There is a reason that Hershel was able to correlate wheat production to sunspots. It is happening again if you care to look at history.
Crop prices are up because of climate disruption. When temps were in the warming mode, production was outstripping demand to the point of many farm foreclosures because prices were substantially below the cost of production. Now it is the other way. Production has become erratic because of the cooling. Yes, we get hot spots, but the overall trend is negative.
One thing to remember when observing the MWP and the LIA. There is ample proxy data to show that both of these events occured globally. Did it happen every place at precisely the same time? No, that is not how climate works. The thing to look at in the literature is was most of the earth warmer or colder on a long term basis. The conclusion that is not disputeable is yes it was. Regionally, there were even more extremes within this time period. Globally, the temp was a bit warmer, and then the temp was a bit colder.
It is really not warmth or cold per se, that will contribute to mankinds distress. It is the fight within the climate, when it does become disruptive, that causes the pain. Man adjusts quit rapidly to a new "norm". It is the transition between these norms that has always, and prob will always be, the time of famine etc.
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Post by glennkoks on Sept 18, 2011 15:37:23 GMT
Sigurdur, excellent points and I think as a farmer you are more in tune than most. The LIA and MWP are pretty well documented as are longer term bond events and other natural climate cycles. And most of the discussion I have read has been about crop production and world food supplies should we return to a colder cycle. However the transition period itself is the reason for this post. If the last several years is a harbinger of things to come we may be in for some very rough years to follow. Not in the mid 2020's but from this point forward.
Crops have advanced and our worldwide production of food has grown since the last colder cycle we experienced in the 1970's. But has it advanced enough to keep up with the massive growth in population we have experienced over the same time?
Even for those who subscribe to AGW. A degree or so in man made warming could easily be erased for the same reasons we have experienced many times in our past. And with that in mind can we handle a climate shift with our current burgeoning population?
The biggest cause of the turmoil in Northern Africa which came to be known as the Arab Spring started in Tunisia earlier this year not as a pro democracy reform movement but as a result of high food prices.
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Post by curiousgeorge on Sept 18, 2011 22:13:27 GMT
Sigurdur, excellent points and I think as a farmer you are more in tune than most. The LIA and MWP are pretty well documented as are longer term bond events and other natural climate cycles. And most of the discussion I have read has been about crop production and world food supplies should we return to a colder cycle. However the transition period itself is the reason for this post. If the last several years is a harbinger of things to come we may be in for some very rough years to follow. Not in the mid 2020's but from this point forward. Crops have advanced and our worldwide production of food has grown since the last colder cycle we experienced in the 1970's. But has it advanced enough to keep up with the massive growth in population we have experienced over the same time? Even for those who subscribe to AGW. A degree or so in man made warming could easily be erased for the same reasons we have experienced many times in our past. And with that in mind can we handle a climate shift with our current burgeoning population? The biggest cause of the turmoil in Northern Africa which came to be known as the Arab Spring started in Tunisia earlier this year not as a pro democracy reform movement but as a result of high food prices. Don't know if you've been following this special on Progressive Farmer, but it discusses in detail the Ag issues facing farmers and consumers in coming years. Worth reading. www.dtn.com/ag/food_security/ |
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Post by glennkoks on Sept 19, 2011 1:05:56 GMT
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Post by astroposer777 on Sept 19, 2011 1:15:14 GMT
Sigurdur, excellent points and I think as a farmer you are more in tune than most. The LIA and MWP are pretty well documented as are longer term bond events and other natural climate cycles. And most of the discussion I have read has been about crop production and world food supplies should we return to a colder cycle. However the transition period itself is the reason for this post. If the last several years is a harbinger of things to come we may be in for some very rough years to follow. Not in the mid 2020's but from this point forward. Crops have advanced and our worldwide production of food has grown since the last colder cycle we experienced in the 1970's. But has it advanced enough to keep up with the massive growth in population we have experienced over the same time? Even for those who subscribe to AGW. A degree or so in man made warming could easily be erased for the same reasons we have experienced many times in our past. And with that in mind can we handle a climate shift with our current burgeoning population? The biggest cause of the turmoil in Northern Africa which came to be known as the Arab Spring started in Tunisia earlier this year not as a pro democracy reform movement but as a result of high food prices. Don't know if you've been following this special on Progressive Farmer, but it discusses in detail the Ag issues facing farmers and consumers in coming years. Worth reading. www.dtn.com/ag/food_security/I think it interesting to note Sigurdurs position in all of this, considering he probably has the most skin in the game, and his decisions about weather conditions, and what to plant, determine his continued success as a food producer. CG has a way of putting things in perspective and providing niche information, which is always appreciated. I perceive that cooling is as inevitable as the sunrise tomorrow, the only question is to what extent and for how long. |
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Post by curiousgeorge on Sept 19, 2011 2:39:30 GMT
Don't know if you've been following this special on Progressive Farmer, but it discusses in detail the Ag issues facing farmers and consumers in coming years. Worth reading. www.dtn.com/ag/food_security/I think it interesting to note Sigurdurs position in all of this, considering he probably has the most skin in the game, and his decisions about weather conditions, and what to plant, determine his continued success as a food producer. CG has a way of putting things in perspective and providing niche information, which is always appreciated. I perceive that cooling is as inevitable as the sunrise tomorrow, the only question is to what extent and for how long. Flattery will get you.  Anyway re: you're last sentance, the same could be said of the Yellowstone caldera, or the next asteroid impact, etc. It's all about probabilities. Which is uncertain territory. |
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Post by icefisher on Sept 19, 2011 4:14:46 GMT
A hot summer in the UK will melt roads, damage train tracks and put the electricity supply under pressure for example. And most of us here do not have air conditioning.
Most who live at the equator don't have air conditioning. In fact the equator gets more than a 100 watts/m2 more annual average insolation than London. . . .and you are worried about 3.2 watts.
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Post by astroposer777 on Sept 19, 2011 4:31:32 GMT
I think it interesting to note Sigurdurs position in all of this, considering he probably has the most skin in the game, and his decisions about weather conditions, and what to plant, determine his continued success as a food producer. CG has a way of putting things in perspective and providing niche information, which is always appreciated. I perceive that cooling is as inevitable as the sunrise tomorrow, the only question is to what extent and for how long. Flattery will get you. Anyway re: you're last sentance, the same could be said of the Yellowstone caldera, or the next asteroid impact, etc. It's all about probabilities. Which is uncertain territory. Some say the world will end in fire; Some say in ice. From what I've tasted of desire I hold with those who favor fire. But if it had to perish twice, I think I know enough of hate To say that for destruction ice Is also great And would suffice. Seriously, I see no evidence that we have a handle on the next "event", whether from a NEO, tectonic, solar, or anthropogenic causes, and I am just aggravated that my kids will have to pay for all of the speculation. |
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Post by Pooh on Sept 19, 2011 4:38:49 GMT
Frost is apt. ;D
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Post by glennkoks on Sept 19, 2011 5:03:01 GMT
astroposer, No one has a handle on the next event. We can't do much to prepare for a NEO or Supervolcano but we can and probably should have some sort of national plan in effect for realistic dangers that have happened and will happen again in the not so distant future.
The famine of 1315 was caused by three excessively wet springs and cool summers in Europe. Even with modern technology I doubt world wide food supplies could hold up to some of the extreme weather events that would likely accompany an abrupt shift from our current warm to a colder cycle.
The threat becomes much more severe if combined with other events like a global pandemic or massive solar storm powerful enough to disrupt our electrical grid.
The global economy is pretty week and Im not sure it can stand on its own if everything remains the same. Add a global pandemic or heaven forbids a "perfect storm" of natural disasters into the equation and the results could get nasty.
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