And then the rains came ...

CHIANG MAI, THAILAND —  “Rain never come in January.”  Malee had overheard me predicting heavy rain for the night, as the black clouds swirled around the steep limestone cliffs at the base of Doi Luang. The clouds tore off in little wisps of vapor, black and menacing, and rose upward, obscuring the jagged, orange-stained, overhanging wall that was visible from Malee’s Nature Lover’s Bungalows in Chiang Dao. She brought 4 cups of home-roasted coffee, a basket of home made spring rolls, and two plates of coarsely cut French fries, stacked high, to the table and set these down in front of us.

“Not big rain, like you say now” she continued, “sometime small rain only.”  She pronounced the word “small” as suh-mawn. As spelled in Thai based on its Sanskrit origins, words that end with the equivalent of the letter “L” are pronounced as we pronounce “N”, which is one of the more endearing things about Thai speaking English, to my ear.

Malee, always cheerful, has been a friend of ours for more than a decade. Orawan and I stumbled upon this amazing place in 1998 while looking for field sites. I was in search of the two Thai pine species that were reported to grow in the area, and we drove up the narrow road that dead-ended at an amazing cliff side Buddhist temple about 1 km past her rustic sign. At that time hers was the only guesthouse in this entire area, surrounded by empty fields and jungle, and local villagers foraged the nearby forests for bamboo, edible plants, and anything else of use. We stayed there one night and it seemed within hours we were friends, and we stayed with her numerous times until about 5 years ago when we stopped working in the region. Malee came to our wedding in Chiang Mai in October 2001, one month after the terrible 9/11 attacks. Coming back here now was like visiting family again after a long absence. In the years that have passed much has changed, and now there are guesthouses everywhere on this road, in the true Thai fashion of mimicking what has proven successful. But still, in spite of the oversupply of copycat businesses, Malee’s is an oasis of peace and quiet, and her business is very successful.

Cliffside buddhist wat near Malee's guest house.

It is true that it is highly unusual for heavy rain to fall between December and April in northern Thailand, the months that comprise the driest part of the annual dry season. In the two decades that Malee has run her business, neither she nor any of her staff can remember heavy January rains like that which we were about to get. In most years it remains virtually rain free from late November until late April, when the heat reaches unbearable heights and the humidity boils up from the Gulf of Thailand. That is when the rains come, in May and June, not now.

The rhythm of the Asian Monsoon, as reliable as your own heartbeat, tracks the movement of the Intertropical Convergence Zone (ITCZ), which follows the migration of the sun’s most vertical ray from the Tropic of Capricorn in the Austral summer, to the Tropic of Cancer in Boreal summer — 23.5 degrees latitude in both hemispheres, respectively.  This is the stuff of Physical Geography 101, and I can still hear the booming voice of the late Dr. Dow, my undergraduate advisor and mentor:

“The ITCZ moves north and south with the seasons, and this means… What?… Brendan! What does it mean when the ITCZ moves north to 23.5 degrees latitude?” The fear that accompanied students in Dr. Dow’s classes was ubiquitous across the room, particularly for those inclined not to pay attention. I thought of Dr. Dow now, and how I am glad that I was one of the students who actually did pay attention.

“I don’t know, Malee, it sure looks like heavy rain to me.” I said.

“Not possible” she replied, “it not rain in January”.

Hours later, as the rain pounded the metal roof of our bungalow with hellish force for two straight hours I thought about how one of the lessons of the prior week’s workshop in Chiang Mai applied to the anomalous weather we were experiencing today. Dr. Andrew Bell, a post-doctoral fellow working with me for the past year, presented work we have been doing for our Greater Mekong Basin project that uses our long tree ring records to inform climate predictions with extremely simple models that even small-scale farmers might be able to use. There are predictions made by local religious leaders from nearly all countries in Southeast Asia, for example in Thai from the Nung Seu Bee Mai Mueng “Book of the Northern New Year” which gives some kind of guidance to farmers. What Andrew has found is that these predictions have some degree of predictive skill simply because climate has a tendency to show persistence from one year to the next, and to statisticians this can be modeled as autocorrelation.

Not only was it raining hard, it was cold too.

This feature of climate data is obvious when thinking about the seasonal shifts that we know well, for example, New York’s winter is cold, so there is a degree of correlation between January of one year and January of the next (i.e., both will be cold). The same is true for the dry season of Thailand — January will be dry in each year, hence the autocorrelation. The anomalous years, however, also tend towards persistence, such that if it is wetter or drier than usual (or colder or warmer, if you will) in a given season, the tendency to remain the same for the next year is slightly better odds than flipping a coin. So, if we assume persistence in the climate we can do a reasonably good job of predicting climate for the following season only. However, if we want to make informed 5-year or longer predictions, so that farmers might make more bold decisions about how and what to plant, and increase their profit margins, we need a better predictive tool than just guessing at persistence.

Andrew demonstrates that by using centuries or more of background data (e.g., long tree ring reconstructions of drought indices) one can do a pretty good job, far better than merely assuming persistence, at deciding what the next 5 years are going to be like, and the longer the record leading up to a given period, the better we do at predicting those next 5 years. The offshoot is more than just deciding what to plant, however. The real prize is in being able to use this information to give some form of blanket insurance to small-scale farmers, known as index insurance, which allows for coverage in case of drought or some other climate index value that is determined to be important. Interestingly, it is not the failure of the crops that is being insured, but the failure in the climate. Whether or not the climate adversely affects the crops is not relevant, as payout is made solely on the basis of climate. And by having lots and lots of small farmers buy into such a scheme, the greedy insurance companies can still make their profits and keep the costs low. For the GMB project, we are tasked with trying to find out how climate and its impacts can lead to conflict, what the parameters are for the conflict, and what factors are necessary to mitigate conflicts when they occur. We always believe that the past can help inform us of our present and our future, so using proxy records in these ways is done with this in mind.

After the rain

The rain had ceased long enough for Orawan and me to walk out to meet our friends Paul and Anna, and their two children, Jonas and Amarita, who had gone out for a late lunch, and we joined them at the Chiang Dao Cave, about 2 km downhill from Malee’s. They sat out the rain in a small roadside restaurant, ordering food by pointing at things that looked appealing and hoping for good results. Paul and Anna are both seasoned travelers, and are no strangers to off-the-beaten-path locations, so they were enjoying their time in the village. We met them and strolled around the neighborhood, finding giant spiders and dead snakes, and an assortment of other horrible things the kids were fascinated with.

By the time we walked back to Malee’s it was near time for dinner, and the rain was beginning again. We had scarcely finished eating around 8:00 p.m. and walked back to our bungalow when the rain began in earnest. Broad sheets of water pounded the roof with a deafening roar until the morning light began to infiltrate our room. It was clear, that for today at least, the rains had come.

When it rains it pours. That phrase entered my mind, as I lay awake, eyes wide open, my wife breathing deeply beside me in the depths of slumber. Malee’s has always been one of the darkest places I have ever been at night, but on this night it was blacker than usual and I had a difficult time making out any features in the room through the impenetrable darkness. I had been having an inordinate number of interpersonal breakdowns with people lately, colleagues in particular, and I considered the notion that often things, negative things, come in groups or clusters, like rain falling. When it rains it pours.  I agonized over the role I may have played, either indirectly or perhaps through callous indifference, in developing these rifts with other people, and I wonder sometimes about karma, and about biorhythms or other phenomenon that can lead to such things. Or maybe it is just the way of the world that sometimes we enter anomalous periods and lots of shit goes wrong. My Vietnamese friends tell me that my age, 53, is a very unlucky year, as is 49.  I don’t remember much about 49, but in truth my 53^rd year has been an outstanding year on many fronts. However, whatever is wrong with the cosmos lately that has me offside of so many people could be just a passing anomaly that will wash away, run off or be absorbed like the heavy January rains on the limestone flanks of Doi Luang.

The message of the day resonated with me.