Quite a lot, really. The observation that climate zones are moving should be enough to convince people who don't "believe" in climate change, but sadly that is not the case. The closer you work with the land, the more up close and personal drought and heat waves and unusual weather events are, and the more you ought to accept what scientists are telling us. The Intergovernmental Panel on Climate Change (IPCC) is out with their fifth assessment report today, which is an update from their last scholarly pronouncement in 2007. It predicts even faster warming and sea level rise for the remainder of the century.

But while the IPCC looks at all the worldwide macro data on climate, their report doesn't contain much of practical import for the Permie who wants to make their own piece of dirt food secure and sustainable. I thought I would start this thread so we can exchange some ideas on how climate change has affected our gardens personally. There are two effects that I have noticed, one good and one not-so-good.

The good change for me is that I am now in climate zone 9. The link above still has my corner of Georgia in zone 8, but that is just the change from 1990 to 2006. In the intervening 7 years, it seems like zone 9 has crept further north. I'm still planning on putting up my seasonal greenhouse this fall; I don't want to take any chances with my citrus trees, especially since this is the first year my blood orange tree has fruit on it. Maybe in another 10 years, we will be in zone 10 and I can forget all about having to put up a greenhouse.

The not-so-good change has been in the variability of precipitation. Anyone who doubts that we have transitioned to a new pattern of droughts punctuated by much heavier downpours is just not paying attention. This year was a horrible year for corn and squash and tomatoes because of too much rain. Even having mine on top of hugelbeds didn't save them. But there was one bright spot in the garden. I had grown some taro plants last year, just on a whim, so there were taro tubers that overwintered in the soil. While everything else was drowning in too much rain back in July, my taro plants were growing like weeds! Which brings me to a climate change recommendation that Permies should incorporate as standard practice:

Climate Change Rule #1: Intercrop a drought crop with a flood crop. As an example, intercrop taro with tomatoes. If it's hot and dry, tomatoes will do well; if it rains every day for three weeks, you won't have tomatoes, but you will have a bumper crop of taro. Anyone think of any other examples?

Something else that has taken off this year are my kiwi vines. I don't know if I should chalk it up to the wet weather or to my mulching them extra heavy last winter. But this year they have finally decided to grow on my patch of heavy Georgia clay. Maybe next year I will get my first fruits from them!

Another thing I have noticed from applying permaculture principles over the last four years since I got this place: there are a lot more critters co-habitating with me now. Skinks, toads, turtles, spiders, millipedes, more toads, salamanders, a big black snake, rabbits, frogs, and did I mention -- toads. I also seem to have less bug problems this year. Must be all the toads chowing down on any squash bug or harlequin bug or grasshopper that dares to invade. Which brings me to another rule

Climate Change Rule #2: Biodiversity is your friend. If species are having a tough time adjusting to the new climate, invite them to stay on your piece of dirt and they will reward you in untold ways. Even go out of your way to move an orb web spider egg sac to a more protected location and the following spring you will have hundreds of little buggers snagging the invading insect armies.

Climate change is going to force a lot of adaptation over the coming decades. Permies are going to have an advantage over conventional agriculture because we already adapt to nature. We're just going to have to be more observant to know what new things to adapt to.

I had a though regarding beds for drought. Make a clay 'dish' and a 'hoogle' out of stone sand and compost. Perhaps incorporating broken pottery because I know newts love digging dens in that. I think the stability of rock would create moisture pockets everywhere (but seriously I have lots of it!) slash the plant of at the top and let the roots rot into the bed.

I think planting for a variety of seasonal possibilities in varied micro (micro) climates is very sound advice. Also planting plants that do well in a variety of conditions like the stinging nettle are likewise probably good bets.

I have other thoughts but I can't seem to think of them just now.

Pretty much everything we need to do to adapt to climate change is already built in the permie mindset.

Diversity as mentioned above. Saving a broad range of open pollenated seed....developing landraces which have deep & resilient genetics, rather than intensively bred plants. Share seeds with others, so if your seed gets wiped out for some reason, someone else has them.

Perennial crops tend to be more resilient than annuals, anyway.

Also, designing for disaster with careful sector mapping: fire & flood in particular.

Understanding how to create and use microclimates.

Store carbon in trees and soil.

And then there are the 'invisible structures' - organizing within the local area to move towards resiliency ala Transition Towns, Bioregionalsm, etc.

Think in 3 dimensions.
Hills, hugelmounds, raised beds. Geography is your friend. No-till is your friend here, as land that is not flat offers more diverse growing conditions.

Anyone who has been growing for a few years will tell you the spring comes a little earlier. The Azaleas used to bloom on the 23rd of March. You could set your clock by it. Now its early march. Rather than global warming or a climate change, a better description would be climate destabilization. The first frost will come earlier, the last frost a little later. Deeper rains, longer droughts. Storms will be more severe. It's not changing from one state to another, there is chaos involved as the planet tries to maintain equilibrium and rebalance the energy in the atmosphere.

Yukkuri hit the nail on the head with the term 'Resilience.' We need plant and animal species that have been through hardship and survived. I had a strain of peas that took a frost. Some plants died, some kept going. I kept the seeds. The next year, a couple of frosts and a hard freeze. Still, some plants made it through and I kept the seeds. I'm thinking 'Great.' Then came the year with 3 weeks of hard freeze. All my seed was in the ground, some of the plants made it through the first week, but it was too much. No seeds, I have to start over. This time, I won't have all my seeds in for the worst part of the season. Staggered planting has its place in developing strains that can endure. It only takes a few years of repeated abuse to develop a strain with greater tolerance for hardship. If they don't survive, it was nothing I'd want to try to grow again. I can see a day when seed cultivars not only say 'resistant to wilt' but also list the growing history '"drought '08, '11, flood '12, hard freeze '13."

There are practices and methods which give plants an advantage. I had some sorgum stalks left standing as a result of not tilling. The squash had the advantage of these stalks offering some extra support during the wind. These squash were deeply mulched. When it rained heavily, the soil was protected from compaction and run off. When it was dry, the mulch held the soil moisture and protected the microbes from day after day of intense sun. I got 5 squash-green hubbards. This is a winter squash, they like it a little cooler. They did just fine in the Florida summer heat, in this sand. Where's that camera?

While we adjust our methods and select for more resilient strains, mother nature is doing the same thing. The squash bugs were awful this year. Of the 5 hubbards, 3 went down to the bugs. My trophy squash seemed to develop a thicker skin sooner. I'll be saving those seeds! The fire ants are holding on just fine. They got me so bad yesterday my feet look like I have smallpox. Disease is another problem. I started 2 spots with corn as part of an experiment with liquid fertilizer tea made with grass clippings. 50 plants became 30 as some sort of stem rust hit them, then 20, then 9. There are 3 remaining, and they don't look good. We can expect to be hit from every direction.

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Here's a shot of that hubbard.

Here is a good source for drought projections: http://earlywarn.blogspot.in/2010/10/future-of-drought-series.html

Take a look for your region and plan accordingly. Get your water harvesting landscaping done sooner than later, and get the trees, shrubs and perennial veggies established.

I expect that much like the sea ice projections these drought projections are off by 60-80 years, and by 2020 it will be obvious to all as industrial ag. takes it in the neck due to climate disruption.

Biodiversity is key.

Like John said, plant drought crops with flood crops. Drought can be a problem with climate change and it has been repeatedly over centuries.
I would say plant Mediterranean and desert crops and crops that need little rainfall (like millets, prickly pears, quinoa...) but also plant very cold hardy crops (like siberian kale or sea buckthorn). Plant also wind tolerant species and be aware of forest fires.

Perennials are much better than annuals in regard to climate extremes.

Andy Cook wrote:Here is a good source for drought projections: http://earlywarn.blogspot.in/2010/10/future-of-drought-series.html

Take a look for your region and plan accordingly. Get your water harvesting landscaping done sooner than later, and get the trees, shrubs and perennial veggies established.

I expect that much like the sea ice projections these drought projections are off by 60-80 years, and by 2020 it will be obvious to all as industrial ag. takes it in the neck due to climate disruption.

Since you bring up the topic of projections, let me put mine out for comment:

Forecast #1: Arctic sea ice will disappear completely at the end of summer by 2017 at the latest. The first ice-free season may be only a couple of weeks, but in succeeding years it will rapidly grow in length.

Forecast #2: The Arctic will transition from an ice covered sea that melts around the edges in summer to an open water sea that only freezes in protected bays and shallow areas in winter. This transition could take a very short time, maybe as short as a decade.

Forecast #3: When the Arctic ocean is ice free, the temperature gradient between the equator and the poles will be insufficient to sustain our three cell circulation in the Northern Hemisphere (the Hadley, Ferrell, and polar cells). Past this tipping point, there will be only one convection cell in the Northern Hemisphere, although the three in the Southern Hemisphere will continue.

This last forecast is the one with the most impact on weather and agricultural systems. The science of meteorology takes the three convection cell circulation of the atmosphere as axiomatic. They have no idea how to predict what the weather patterns will be with one cell, and will need a few years of experience and data collection with the new circulation to be able to understand it. The only scientists that are conversant with one cell circulations are the astrophysicists that have observed them on other planets.

The impact of a change to a one cell circulation could be enormous. Part of the reason that most of the world's deserts are found at around 30 degrees of latitude is because that is where the boundary between the Hadley and Ferrell cells is. Both cells have descending air that has lost its moisture at that latitude, hence the dearth of water available for precipitation. In a one-cell Northern Hemisphere, the location of deserts may be completely different, clues to that being found in the geology of the Miocene Epoch.

Although I am a chemist and not a climate scientist, I've done a bit of reading on the subject, and the fact that the models are all lagging the observed data is disconcerting. It means we need to speed up our efforts, as you correctly notice, to get our swales, water catchments, and hugelbeds in place.

Haha John,

I teach Life Sciences and am the HoD of the science department at an international school in a BRIC country.

I'm in complete agreement with the points you outline. The only additions are two:

1. The cause of the Arctic Ocean going ice-free so quickly after the loss of the summer ice: A cooler fresher layer of water approximately 80 meters thick overlays the remaining warmer saltier water underneath. The increased salinity increases the density, which is why the warmer water is underneath the colder water. The deeper layer is 5-6 degrees C warmer than the upper layer. Once the upper layer warms sufficiently it will mix with the lower layer. . . .and poof! No more winter ice in the Arctic.

2. Then the NH weather/climate comes off the rails, perhaps as quickly as from one growing season to the next, with the resultant circulation system as you outlined. Then warming accelerates, much like how a glass of coke warms up rapidly once the ice cubes are gone, and the associated permafrost/clathrate meltdown and increased loading of atmospheric GHGs.

Andy Cook wrote: much like how a glass of coke warms up rapidly once the ice cubes are gone, and the associated permafrost/clathrate meltdown and increased loading of atmospheric GHGs.

Here's where I begin to hedge my bets. That ice cube sitting on top of Greenland is BIG, and will take a LONG time to melt. While it's still there, I can imagine that the north coast of Greenland and the Canadian Arctic Archipelago will freeze over in winter for decades to continue.

Same thing with the permafrost that holds all the clathrate. Some of it is pretty thick, so it may take centuries to melt. I don't think the clathrate is waiting for a nucleation event, like a Mentos in a soda bottle, to come bubbling up all at once. I'll put my money on a long, slow release.

But then again, I could be wrong.

The Eastern Siberian Arctic Shelf is the size of Europe and on the opposite side of the Arctic Ocean from Greenland. It is now ice-free every summer, and has an average depth of about 70 meters. So. . . the seasonal warming goes right to the sea floor. Plus warm Pacific water enters via the Bering Strait.

Closer to Greenland is the Kara Sea: http://onlinelibrary.wiley.com/doi/10.1002/grl.50735/abstract

Snip:

"[1] Since the Last Glacial Maximum (~19 ka), coastal inundation from sea-level rise has been thawing thick subsea permafrost across the Arctic. Although subsea permafrost has been mapped on several Arctic continental shelves, permafrost distribution in the South Kara Sea and the extent to which it is acting as an impermeable seal to seabed methane escape remains poorly understood. Here we use >1300 km of high-resolution seismic data to map hydroacoustic anomalies, interpreted to record seabed gas release, on the West Yamal shelf. Gas flares are widespread over an area of at least 7500 km2 in water depths >20 m. We propose that continuous subsea permafrost extends to water depths of ~20 m offshore and creates a seal through which gas cannot migrate. This Arctic shelf region where seafloor gas release is widespread suggests that permafrost has degraded more significantly than previously thought"

Takeaway: the subsea permafrost is not the impermeable barrier that it was once thought to be.

Anthropogenic warming is speeding things up a bit towards the end, but the process of permafrost destabilization also occurs from the geothermal heat coming from below. This process has been going on for 6-8 thousand years, albeit more slowly than the past few decades. Typically Earth would have tipped back into a cooling period about 6,000 years ago. If that process had not been interrupted by the anomalous stability of the warm Holocene the glaciers would grow, sea levels would drop, and the shallow ocean shelves around the Arctic Ocean would have been re-exposed to the Arctic Winters and the -50 C temps, thereby re-freezing and keeping the permafrost intact. The opposite is occurring as we are too well aware. Semiletov and Shakhova et al estimate there is 50 GT of free methane gas trapped below the disintegrating subsea permafrost layer just waiting for a pathway. That is the figure Wadhams et al used in their recent paper estimating that the release of that trapped free methane from 2015 to 2025 would cost the global economy 50 trillion dollars. Personally I abhor reducing the natural world to USD, but they didn't ask me.