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Dan, I'll try to answer your questions about the Sun in what follows. I don't have anything much to say about predictions about this years agriculture from USDA; it's not my area of expertise and as Homer Simpson said: "predictions are hard, especially ones about the future".
Having said that, the research grouping of which I'm a part has been making excellent progress in finding out how to predict solar activity in the medium and longer term. Once we can accurately predict short term solar activity, I predict the Sun will suddenly be back in vogue as an important climate variable...
But you asked why it is that despite the protracted solar minimum (about a year longer than normal) and the less than previously active current solar cycle haven't prevented the last decade from being the warmest in the recent past (last millenium).
The answer lies in Earth's oceans.
When you compare solar cycles longer term ups and downs, it is evident that there is approximately a one cycle lag between solar activity and its resulting effect in the climate system. The reason for this is that water has a high heat capacity - it takes time to warm it up, and it takes time for it to cool down once it's warm. Although the last decade has been warm, the surface temperature hasn't increased, and according to some metrics, the ocean heat content has been in decline. In other words, the surface has been maintained at a high temperature at the expense of the temperature further down in the ocean.
The co2 global warming theorists have been saying that it's perfectly possible for natural variation to cause a cessation of global warming for a decade despite the fact that co2 in the atmosphere has increased from 0.037% of the atmosphere to 0.039% of the atmosphere over the period. The implication is that the oceans are capable of retaining heat on decadal (and multi-decadal) timescales. This being the case, we need to reconsider the reasons why the co2 theorists say the Sun can't be the main driver of the recent warming.
The absolute amplitude of the solar cycles has been gently dropping since a high point in 1958. However the subsequent cycles were still historically high and also short, with brief minima and steep up and downramps. This means the avearage sunspot number (a good indicator of Total Solar Irradiance) was high compared to the earlier part of the century.
The ocean absorbs and retains the solar energy entering it. When the sunspot number is below about 40 per month, the ocean cools. When the sunspot number is above 40, it warms. The average over the 1956-2003 period was over 70. The result of that is that the ocean heat content increased.
The Ocean has as much heat capacity in the top ten feet as the entire atmosphere above it. The global average temperature of the lower atmosphere (troposphere) follows along behind the ocean surface temperature by several months. The ocean drives the atmospheric temperature. But it doesn't do it at a steady rate. The major climate related phenomenon related to big releases of oceanic energy into the atmosphere is the ENSO, the cycle of successive El Nino and La Nina events. This oscillation is what caused the big spikes in global surface air temperatures in 1998 and 2010.
Both those events and the previous three bigger El Nino events followed shortly after Solar minimum. This is when the ocean flips from heat absorbing mode into heat release mode. What goes in must come back out in energy terms. The best time for this to happen is when less solar energy is being pumped in than usual, i.e. at solar minimum. This is the reason for the loose synchronisation between El Nino and Solar cycles. I say loose, because there are other factors affecting ENSO which I'll leave for another day.
The main points I'm trying to communicate in this post are that just because we don't see an immediate one to one relationship between solar activity and climate metrics such as surface temperature, doesn't mean it isn't a major driver of the system once you understand the chain of causality.
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