If climate change was real and effected agriculture

Assuming it was not based on flawed data, fraudulent scientific papers and exaggerated media claims used in UN documents. Assuming the world was warming and that changed growing patterns world wide, what would we do?

1. We would need to retrain millions of farmers. Formal training for farmers, not agronomists, ordinary farmers, is needed anyway. Over 60% of Australian farmers are past retirement age. We need to train people to replace them anyway. Farming is not for amateurs. 80% of the third worlds farmers need training too regardless of climate change. Private, web or magazine based teaching is the cheapest option for agricultural extension with some investment in vehicle mobile teaching tools in remote areas. 
2. As seasonal patterns shift farmers will need to change their choice of seed stock and crop variety. Seed company's have ample diversity in different seed stocks for wetter, drier, colder and hotter growing conditions. 
3. Some farmers will need multiple on farm seed storage for several varieties so they can buy cheap, store long, sow what they need in rush without running fowl of a scramble for seed stocks and rising prices when it apparent that they will need a given seed type.
4. We need to plant wind brakes, hedges and grass hedges [Lev 19:9]. These block hot and cold wind, flows of frost carrying cold air and by stilling the air over the field it reduces evaporative water loss. It can with good design modify the temperature back to the pre-greenhouse temperature where desired. If fodder, fruit or nut yielding trees are used they are an investment with a quicker return than wood. Such plantings should be tax deductible and should be depreciated as machinery is.
5. When greenhouse models predicted increases in rain fall the IPCC painted it as bad by calling it Increased rainfall variability and talking about flash floods. That sounds bad but by simply adding artificial bends and meander in streams, overflow channels and ponds we can catch these rains. 
6. At the smaller scale swales* or ploughing with a Yeomans** aerating plough make the water move into the ground rather than running off. The key is to hold the water on the land long enough to allow the water to move into the water table where it moves very slowly and feeds springs that run deep into the dry years. The most extreme but effective means of doing this is terracing. Even with all our modern technology we do much less terracing of farm land than our bronze-age ancestors did. why?
7. Where increased drought is predicted we need cisterns. Covered water storage and underground canals. Ancient man could build these in the stone age. Can't we do better? Developing ways to make them cheap and easy to build should make you rich.
8. Also in deserts we need to move to more drought tolerant crops with drip and underground porous pipe based irrigation. This makes the desert bloom. This means a shift from water hungry crops to things like dates, olives and fruiting cacti but moving from one mono-culture to another leaves you vulnerable. Mixing up different species and value adding removes the vulnerability to fickle market fluctuations. The boab tree seedling is the latest new desert cultivar. http://www.boabsinthekimberley.com.au/
9. We are the first generation that don't move livestock away from drought enough. We also need to be ready and equipped to move livestock away from flood zones early. Using farmer to farmer agreements as a form of insurance and looking at transport and agistment for livestock as part of a drought insurance process. While individual regions are drought stricken often there is another accessible region that is not. If done well it could be cheaper than current government drought assistance. 
10. We need to give our gazing land time to grow high and put down roots deep restoring soil carbon. This drought proofs and flood proofs farms. If we allow the animals to graze land too sparely they bite back the recovery growth and the grasses can't grow strong and deep, they have no energy. There is a solution Holistic Management created by Allan Savory and Jody Butterfield. http://holisticmanagement.org/
11. Where floods are an increased risk we need to make hills creating high ground where there was none, so people and livestock can get above the torrent. About half the farms have the necessary equipment. The channels we dig to get the earth will catch flood sediment and retain water long after the flood is gone remaining green as the rest of the land browns.  
12. We need to domesticate many new species. Why fear flood if you livestock is Hippopotamus or Capybara. Why fear drought if your farming a drought tolerant native desert grass or the boab. We are domesticating two new species a month world wide. If we farm endangered species, e.g. the American buffalo, we find that their population recovers. Why not farm seals for the skin and meat? Why not keep a hairy nosed wombat on your farm as a wild pet? Numbats and monkeys are good eating I'm told. Properly farmed they could feed millions.
13. In the most extreme cases of weather based disruption we will need to build greenhouses and hydroponics. These are getting cheaper by the year and are far cheaper than replacing our energy infrastructure. They can be fully climate controlled. Climate change is irrelevant; They would work on Mars and even Venus. The air can be cooled with solar powered air-conditioning, heated with solar thermal and all water can be in theory retrieved and recycled by solar powered dehumidifiers. In practise it might be cheaper to deal with transpiration losses by hauling in water by rail or even truck. 
14. We may need to develop radical new technologies: Machines that convert cellulose to starch, algae farms to supplement livestock feed supplies. These too can be air and water tight, recycling everything if needed to be. Even Food nano-fabricators are not in theory impossible there are people working on them today.

All these things are doable, some may not be cheap but a little more inovation could make them as cheap as modern computer chips. Remember when a cheap computer cost a million dollars?
Most of these things will need to be done anyway. If the government tries to do them it will never have enough money. Only by tapping the tools of the free market and developing new tools to capitalise individual farms and farmers (education and agricultural extension) will we succeed.
World population is growing; Food production has always grown to match. The climate is always changing we need to be ready for anything. We have the tools and techniques its not impossible to adapt to anything.


*If you don't understand any term feed it into wikipedia.
** Water For Every Farm. Using the Keyline plan. By P.A.Yeomans.  http://www.keyline.com.au/   also uses swales.
Australians Bill Mollison and David Holmgren developed some of these ideas into Permaculture. I recommend a Permaculture course. I've done one. Find a teacher that's greenhouse neutral, there are a few.