ASIAN SEED − 27 Solar-induced Crop Calamity Our star is entering into a state of slumber; the seed industry should take heed. The sun, which is the enabler of photosyn- thesis, and an influ- encer if not driver of Earth’s climate sys- tems – factors which crop seed production directly depend on – has already begun what could be an extended state of slumber. Measurements of sunspots, solar wind, space weath- er, cosmic rays and other solar-influenced geomagnetic forces observed during the current Solar Cycle 24 – which began in 2008, and is set to conclude by 2020 – fore-shadow an even weaker Solar Cycle 25, which is on track to be one of the qui- etest cycles in recent history. Indeed, a growing number of climate scientists predict the upcoming cycle to be the start of a new Grand Solar Minimum (GSM). Some have suggested that the cycle could begin earlier than expected, as soon as 2019. Har- bingers include: total solar irradiance (TSI), geomagnetism, cos- mic ray flux, volcanism and cloud albedo. Al- ready in 2018 – and at least since 2016 – the effects of a weakening sun on agricultural productivity are plain. As the sun goes to sleep during Grand Solar Minima, Earth’s climate and weather systems wake up. Extreme weather events and great transforma- tions can take place, driven primarily by atmospher- ic chemis- try linked to the sun – that is, without fac- toring for human influences on weather and climate. Adverse effects on regional and glob- al food production arising during the most recent GSMs are well-documented. For example, during the “Little Ice Age”, a relatively cool period between the 17th and 19th centuries marked by two GSMs (the Wolf and Maunder minima), food famines and shortage-induced unrest were the norm. If, indeed, a new GSM is upon us, history teaches us to beware of the following: 1) Less sunshine reaching the plan- et’s surface (TSI) 2) More clouds blanketing the earth’s lower at- mosphere (cosmic ray-induced cloud albedo) 3) Extreme and rapid changes in rainfall patterns (ITCZ) 4) An uptick in large-scale volcan- ic eruptions Combined, these factors have signifi- cant potential to alter seasons, and thus productivity across the planet’s conven- tional grain and green belts, which already looks to be shifting away from temperate zones and towards subtropical or tropical regions. Can we better imple- ment programs for effective geographic and crop-wise seed breeding and multipli- cation? You bet, but first we need to look at how these changes affect agriculture. EVER-FLUID ITCZ Formally known as the Intertropical Convergence Zone (and familiarly as the “doldrums”), it is a belt of low pressure that strad- dles the equator between 15 de- grees north and south latitude. The ITCZ powerfully influenc- es global weather, affecting jetstreams, monsoons and rainfall patterns. Every year, the ITCZ migrates from its northernmost posi- tion in January to its southernmost in July, oscillating between the seasons (see image on next page). This annual migration is forced by temper- ature budgets (the flow of incoming and outgoing energy is called Earth’s ‘energy budget’), especially over large land mass- es, and brings south- westerly monsoons to South and South- east Asia during the Northern Hemisphere spring and summer periods, typically from June to November. Then, during the other six months of the year, cooler weather in higher latitudes forces a southward migration of the ITCZ, which coincides with northeasterly monsoon winds that bring wet and windy weather to subtropical and tropical areas, especially the tem- perate and subtrop- ical coasts lining the South China Sea. Farmers and seed multipliers increasingly experience what is commonly described in news reports as “unseasonable rain” or “unusual drought”. Since the peak or maximum of Solar Cy- cle 24 around 2015, a key driver of much of this erratic weather is shifting or expanding coverage of the ITCZ. This shift can be linked to our planet’s weakining magnetic shield. When aver- age temperatures in temperate climes plummet (as they tend to do during periods of extremely weak solar activity), the ITCZ’s average position moves fur- ther south, oscillating and expanding in a new pattern, driven by convective forc- es of the relatively warmer equatorial zone. Convention- ally-arid areas may bloom with rain-fed flora, attracting hosts of migrating birds, other vertebrates and invertebrates (includ- ing, need we say it, pests). A number of recent crop-loss events may be attributable to a shifting ITCZ. As highlighted in the map on page 27, agricul- SIGNS: We are due to hit the trough of the current solar cycle by 2020. Measurements of sunspots, solar wind and geomagnetic foreshadow climate chaos. Image: NASA