As the United Nations' OCHA explains, this is related to an El Niño event in the eastern Pacific - warming of surface ocean waters leading to changes in weather patterns across the world. While some areas become drier, others will experience higher rainfall leading to flooding and higher sea levels, the latter especially trying for low-lying islands.
But is it proof of "global warming"?
The US National Oceanic and Atmospheric Administration (NOAA) has historic data of ocean temperature variations in the El Niño-prone region going back to 1950 (1). The 3-month period from last December to February 2016 saw the highest positive variation from mean, ever (2.2 degrees C).
However, sceptics could say (a) there are always difficulties with methodology in measurements like these and (b) 65 years is not long in geological terms.
It also depends on how you sample and present the information. Typically, the highest average surface ocean temperatures are found in the September-November period:
The pattern is similar to that in the first graph, but what happens if we start looking at years, rather than rolling quarter-years?
This year still looks exceptionally warm. Yet take 5-year averages and the picture changes significantly:
On that basis the current El Niño is merely returning us to the average point. And look at the pattern for rolling 10-year averages:
Taken as a whole, the last decade has actually been cooler! In fact, since the decade 1992-2001 the rolling 10-yearly averages have all been on or below the mean. If reversion to the mean is to be expected, we should be anticipating some more years of above-average temperatures as a correction.
This doesn't at all help the nations now in crisis; but help is coming, and as ever it has political implications. In a Radio New Zealand interview on Friday, Mark Adams of the International Organization for Migration stressed the logistical difficulties of assistance from the Philippines and the USA's west coast; yet a couple of weeks ago the Federated States of Micronesia issued a press release reporting a visit by the Chinese Ambassador, who announced a "10 million RMB worth of equipment specifically to address and mitigate the effects of the drought."
It has been said that the Chinese ideogram for "crisis" is a combination of elements representing "danger" and "opportunity". Even if its meaning is more correctly explained as "critical point," the notion may have relevance for Western geopolitical analysts looking at the Pacific region.
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(1) http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml
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