Each spring, farmers look forward to the thaw, a natural heating up of frozen ground as it turns soft under balmy climate conditions. When the ice melts away and the soil warms, spring growing season has officially begun.In recent years, however, spring thaw dates have come earlier, making them harder to forecast. And as a result, we might just see even more price increases than we expect!
NASA scientists have recorded an earlier regional thawing trend across northern high latitudes, advancing almost one day a year, since 1988. This trend, a likely result of global warming, leads to a longer growing season and supplies more time to harvest, which on the surface can be seen as positive. Some new studies, though, warn that this situation could actually increase the effects of climate change in the long term.
Why? Early thaw has the potential to alter the cycle of atmospheric carbon dioxide intake and release. A longer growing season promotes more carbon uptake, which is then stored in seasonally frozen and permafrost soils. But when permafrost soils thaw and dry out, higher temperatures in the fall promote release of the stored carbon back into the atmosphere. This process is projected to increase over time at an accelerated rate, sending carbon dioxide levels soaring and further warming the planet.
The “Easter Freeze” of 2007, which devastated many crops in the region, and shot up prices, showcases another alarming trend — the occurrence of late-season frosts following an earlier thaw date. Thaw-and-freeze is a process that occurs when temperatures change above and below the freezing point, with plenty of moisture in place. Repeated thaw-and-freeze can cause damage to buildings, bridges and archaeological sites. It can also create problems for wildlife, natural plants and crops.
Expect more crop and natural plant damages in winters and early springs. Early springs make plants particularly vulnerable to late-season frosts, and the resulting young, tender plant tissues tend to be prematurely developed.
And, as plants start to grow earlier in the spring, they also stop growing earlier in the fall — even though temperatures are still high.
Best bet is to check out the frozen and canned fruits and vegetables.
Remember that these are packed at the peak of freshness — not only better taste and better nutrition (read the labels carefully to ensure that no other ingredients are listed, such as high fructose corn syrup), but also better prices.
Phil Lempert is food editor of the TODAY show. He welcomes questions and comments, which can be sent to . For more about the latest trends on the supermarket shelves, visit Phil’s Web site at .