2010 will go into the record books as one of Jamaica’s wettest years, even without a direct hit from a tropical storm or hurricane.  By the end of November, Montego Bay had seen more rainfall than it got for 12 months in the hurricane years of 2005 and 2007.  Total rainfall for 2010 will be more than 65 inches – about 14 inches more than the long-term average.

Tropical Storm Nicole contributed about a quarter of this year’s total but we were well on the way to a fairly wet year even before the September floods.

For 2010 so far, only January, April and November have produced less than average rainfall in Montego Bay.  Even without that soggy September, total rainfall for 2010 so far is greater than the full-year totals for 2008 and 2009.

Why is this important?  The first effect has been, and will be, on agriculture.  The Caribbean Institute for Meteorology and Hydrology (CIMH) keeps track of rainfall and soil moisture in 16 Caribbean countries, including Jamaica.  CIMH reports that for the year to the end of October 2010, Jamaica on average was “very wet”.  The latest report shows soil conditions returning to normal.  The outlook through January 2011 is for “normal to above-normal” rainfall, with warmer than usual temperatures.

That could mean a good recovery from this year’s setbacks in crop farming.  It will require careful management to make sure that fields are properly drained when it rains but water is saved to use when it isn’t raining.  It should also require more attention to preventing soil erosion and reducing the use of chemical fertilizers and pesticides.  Without this care, heavy rain can choke nearby rivers with mud and debris, or poison them with chemical runoff.

The second effect of a wet year is on the sea.  The storm season brought long periods of cloudy weather and a massive injection of cooler water, both from rain and from the mixing caused by storm surges and big waves.  Sea surface temperatures are still warmer than average, but according to NOAA’s Coral Reef Watch, no longer dangerously warm.

As recently as the end of August, NOAA was still suggesting that Jamaica’s coral reefs were at risk for “widespread bleaching”.  (Coral bleaching happens when corals lose the algae that live in their cells, help to feed them, and give them colour.  If it continues for more than a week, the corals die.  “Thermal stress” – bright sun and warm water – is the main cause.)

Since September, the three-month thermal stress outlook for Jamaica has been getting steadily better.  The latest Coral Reef Watch report shows no bleaching risk for almost the whole Caribbean, including Jamaica.

This doesn’t mean our reefs are completely safe.  Storm runoff carries a lot of things into the sea that don’t belong there, like soil, debris, garbage and pollution.  This runoff can smother or poison the reefs and the creatures that live there.  On this front there has been little progress.  Montego Bay continues to grow with no proper drainage plan, so flooded streets and plumes of dirt in the sea are still regular events.  Gullies cleaned to the concrete in September are hip-deep in garbage again.

Nature has done its part to buy our reefs a little time.  Better land use planning, that looks at whole watersheds from mountain top to sea floor and corrects some past mistakes, is the only way to keep them really safe and productive forever.