Category Archives: Hurricanes

The unbelievable coincidence of Cyclone Ockhi, Mumbai and me

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On Monday evening, I will travel to Mumbai, India. I am going there for a research project in which we are trying to assess the risk that Mumbai might someday be hit by a tropical cyclone, particularly one strong enough to cause a significant storm surge and a major disaster for this low-lying coastal megacity. The problem is scientifically interesting – and difficult – precisely because such an event has not happened in modern history. So one can’t use historical data as a guide, although we know the risk is not zero – we believe that it has probably happened sometime, but it’s very rare our records are just not long enough. One has to use models of some kind to assess the risk, and our problem is to develop, evaluate, and use those models. (And climate change is most likely increasing the risk, but that’s another issue.)

Anyway, at this very moment there is a cyclone, named Ockhi, in the Arabian Sea. It is forecast to pass quite close to Mumbai on Tuesday evening, precisely when my flight (booked several weeks ago, and planned long before that) is due to arrive there!

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While the storm is pretty powerful now, it is forecast to weaken a lot before landfall, so it will probably not cause a major disaster. And the models have it making landfall a bit to the north of Mumbai anyway (although with the uncertainty in the track forecast, a more direct hit is still possible). So this probably won’t be quite the disaster our project aims to address, but still, the coincidence is profoundly spooky. There are only 1-2 cyclones on average each year in the Arabian Sea, and most of those never come anywhere near this close to Mumbai. It’s an *extremely unusual* event, and it’s happening *precisely* as I’m coming to town to study it.

Harvey commentary

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Some further commentary on Harvey. Mostly (but not all) about the climate connection.

Global Warming’s Role in Hurricane Harvey (The Takeaway, NPR)

Why Harvey’s devastation is so severe (CNN)

Climate Change Didn’t Cause Hurricane Harvey, but It Made It Worse (Fortune)

Commentary by Columbia Scholars (not just me)

Meanwhile, Hurricane Irma is breaking records and looking truly fearsome in the Atlantic.

Patricia’s ultra-fast intensification

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I have a piece in CNN today about the incredibly fast jump that Hurricane Patricia made from tropical storm to what some people are saying should be called “category 7”. I point out that this case shows vividly why we need advances in the science of hurricane intensity prediction, at the same time as funding for this work was severely cut earlier this year. And, I compare Patricia to The Hulk.

Earlier, before landfall, Allison Wing and Chia-Ying Lee wrote an expert but accessible analysis of what the storm was doing and how the forecast models failed to capture it.

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The extreme state of the Pacific climate

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I have a post up at the Columbia Earth Institute State of the Planet via the Initiative for Extreme Weather and Climate, on the current El Nino event, recent Madden-Julian Oscillation, typhoons and hurricanes, and everything else going on in the tropical Pacific now, as well as its impacts on the US, and the ramifications (including some pretty speculative ones) for the global climate.

On Sandy’s return period

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I’m making it a bit of a mission to recruit younger colleagues, especially postdocs and graduate students, to try writing for nonscientist audiences. In this piece, new PhD Madeleine Lopeman (Columbia Civil Engineering, just defended her thesis, advisor Prof. George Deodatis), explains how her innovative extreme value analysis of tide gauge data at the Battery yields a lower return period for Sandy than all previous ones – meaning maybe it wasn’t all that rare an event after all.

An interesting question is what relationship there is, if any, between return periods defined for different characteristics, either of the storm itself or its impacts. Tim Hall and I published a paper in 2013, for example, that estimated a 700-year return period (95% confidence interval 400-1400 years) for the track of Sandy – strictly, for a storm with at least category 1 intensity intersecting the New Jersey coast at an angle at least as steep as Sandy’s track did. Despite the different numbers, our estimate could be consistent with Madeleine’s, because the numbers describe two different things. It’s reasonable to expect the return period for the flood at the Battery to be shorter than that for the track, because one could get the same flood from tracks coming in at shallower angles if the storm had stronger winds, or made landfall closer to NYC.

Tug in the surge: Capt. Forsyth’s Sandy story

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After reading my book Storm Surge, Capt. Mike Forsyth sent me an email, in which he included the story of his experience in Sandy. It’s a good story, and so with his permission, I am putting it up as a guest post here. What follows is Capt. Mike’s self-introduction, followed by his story.

–Adam

I was born and raised on Staten Island, spent two weeks of most childhood summers on Long Beach Island, NJ, and as an eight-year-old child was brought by my parents to LBI to see a navy destroyer put up on the beach by the Ash Wednesday Storm.  I am a tugboat captain, and work for a New York-based tug and oil barge company.  If, as “W” said, America is addicted to oil, I am a mule.  However, I have been intellectually convinced of the reality of climate change since the mid-1990’s.  This was reinforced by a conversation with a meteorologist about a destructive line of storms that came through upstate New York, where I now live, on July 14th, 1995.  The reality was driven home, quite literally, when a similar line of storms did $45,000 damage to my home in a few seconds on Labor Day 1998.  I support candidates, donate money, keep myself informed, try to reduce my own carbon footprint, and speak out on the issue when the occasion arises.

My Hurricane Sandy Story 

© 2015 Capt. Mike Forsyth

In October of 2012, I was captain of the tug Stephen-Scott, engaged in moving Reinauer Transportation Company’s oil barges in the Northeast.  I worked on another Reinauer tug on the Gulf of Mexico during the previous year’s hurricane season and spent a good bit of time following forecasts and tracking storms on charts.  On Wednesday morning, October 24th, I drove to Reinauer’s dockyard, at Erie Basin in the Red Hook section of Brooklyn, parked my car and started my two week tour of duty.  Almost immediately, I started paying attention to Sandy while she was still in the Caribbean.

On Saturday morning, October 26th, I received orders to take a 60,000 barrel barge loaded with diesel fuel from a New Jersey refinery to Newburgh, New York, about fifty-five miles up the Hudson.  By that time, it appeared likely that the storm would impact New York Harbor.  The Hudson River at Newburgh is within the US Coast Guard Captain Of The Port (COTP) of New York zone, and the USCG had issued a storm-related notice requiring commercial vessels staying in the COTP NY zone to file a “remain in port” plan.  My plan was to depart with the barge that evening as ordered, and arrive early Sunday morning at the oil terminal in Newburgh, discharge the cargo of 2.5 million gallons of diesel fuel, then anchor in the Hudson River off Newburgh until New York Harbor was re-opened to navigation.  The plan was received and approved by the COTP.

The prediction for the storm surge was then four to eight feet.   The paved parking area at Erie Basin is at dock level, probably seven or eight feet above the high water level.  I expected that there would be some water running across the pavement or possibly a little ponding, if the storm hit at other than low tide.  My Honda Element has good ground clearance, but that would not be enough.  Before my boat left Erie Basin that Saturday, I drove to the Pep Boys auto parts store in Park Slope and bought a couple of oil-change ramps.  Back at Erie Basin, I put a staggered stack of 2×12″ lumber about 8 inches high in front of each rear wheel, and put the oil change ramps in front of the front wheels, and drove ahead and up.  I figured that would keep salt water out of the engine compartment, and maybe keep the brakes and suspension out of the water.

Our barge discharged its cargo on Sunday, October 28th, and we dropped anchor in the Hudson between Newburgh and Beacon at 8:50 that evening.  I was following the forecasts, and had the feeling that my precautions with my car were pitiably, laughably, inadequate.  An 8 to 11 foot surge would float the car off the blocks, and fill it with harbor water.  Monday morning I checked the forecast, and called my insurance agent to make sure that my comprehensive insurance included flood damage.  She confirmed that, and gave me the telephone number for claims, which I told her I expected to use later that week.  There was absolutely nothing more I could do.

Within an hour, I got a phone call from Chris, the captain of the tug Jill Reinauer.  He told me that his boat and the Kristy Ann Reinauer were at Erie Basin and their crews were moving all the cars they could to higher ground.  I told him where my spare key was.  I told the other tug and barge crewmembers to call the Jill or the Kristy, so that their cars might be saved.  I woke up my first mate, Davey, and asked about his spare key.  He told me that his new car had a “smart” key, so smart that a new one cost about two hundred dollars, so he hadn’t had a spare made.  Too smart for its own good, his car was a total loss by nightfall.  Someone sent him a cell phone video of his car, doors-deep in water with the lights flashing and windows going up and down while the salt water shorted out the electrical connections.

Sunday night and Monday, several other tug and barge units had joined us at anchor off Newburgh.  Monday afternoon and evening, the wind and rain came through, fierce, but a pale shadow of what had befallen the coast.  Like the other captains and mates, we kept a close watch on GPS chart plotters and radar, in case the wind and current caused a vessel to drag anchor.  I also watched our depth sounder, and compared the readings to the charted depth and the predicted normal tidal changes.  The depth under the keel reached the predicted maximum early, and continued to increase.  On the electronic display of our depth sounder, I could see the storm surge from Sandy pass under our keel, several feet above the maximum predicted by the moon and the sun, while a powerful current carried this surge of water upriver.

On the chart plotter, a neat circle, centered on the spot where our anchor had dropped, circumscribed what should have been our range of motion in any direction.  The “own ship” icon on the chart plotter crept slightly closer to the edge of the circle.  I started the twin 1,700 horsepower engines and put the propellers in gear at low speed to try to oppose the force of the surge.  The radar range to the next vessel anchored up river began to decrease, and it was clear that our anchor was dragging.  I have dragged anchor numerous times on the Hudson.  However, that usually happens when gravity carries the run-off from heavy rains or snow-melt down from the hills and mountains, adding fresh water to the ebb tidal flow, and usually with a northwesterly gale blowing as well.  I have never, before or since, dragged anchor on the flood current of incoming ocean water  in the Hudson.  We picked up the anchor, stemmed the tide under power, and when the surge had passed, we re-anchored, and remained there until November 1st.  We moved down to the section of river off the Upper West Side of Manhattan, and anchored for another two days, until portions of New York Harbor were re-opened to limited navigation.

During this time at anchor, I received welcome news that my car had been moved from Erie Basin to the roof of the parking garage of the nearby Gowanus branch of The Home Depot, and then returned to Erie Basin, none the worse for the experience.  Some cars were moved from Erie Basin, but parked in the lower level of the Red Hook Ikea parking garage.  They did not fare as well, since all basements and first floors in Red Hook were inundated by the surge.  About forty cars were saved.  Returning to Erie Basin on November 4th, I counted twenty cars and pickup trucks belonging to fellow employees which obviously had not been moved out of harm’s way.  I was puzzled by big dents in the roofs of some of them.  Then I saw some anchor buoys, yellow-painted hollow steel balls about four feet in diameter which are used to mark the location of dredge anchors.  These had obviously come from the far side of Erie Basin, and were on the pavement by a chain link fence which is the boundary of the employee parking area.  They apparently floated across the basin, blown by the wind, until they came up against the fence, floating above the parked cars.  The dents in the roofs were made by the steel buoys, bobbing up and down on waves and pounding on the roofs.  The oil change ramps would not have done the job.

The waterfront was dramatically changed by Sandy, with destruction and large mis-placed items all around.  Most striking for several days after the harbor re-opened was the absence of lights.  For decades, New York mariners have been complaining about light pollution, more numerous and brighter lights on shore, which impair night vision and can make buoys and navigational lights difficult to see.  The power was out at most waterfront facilities, including oil docks, for a long time after the storm.  Here and there were construction lights from a portable generator, or an isolated dock which had power restored, but mostly we had a dark shoreline for a couple of weeks.  With most of the oil terminals in the metropolitan area out of commission, I reflected that the 2.5 million gallons of diesel fuel which we delivered probably was put to good use in the immediate recovery from the storm, since Newburgh had some of the closest oil terminals to New York which were still in operation.

At the end of my two weeks, I was able to drive home in my own car, thanks to efforts in the teeth of the storm by the crews of two tugboats, and to the people at the Gowanus Home Depot.  The tugboatmen did something above and beyond the call of duty or any job description, bordering on heroic.  Boatmen don’t have to do these things, but no one in the business is surprised when they do.  It is almost expected.  (The first four Apostles were boatmen, not farmers or shopkeepers or divinity students, and the choice was probably well-considered.)  However, the folks at Home Depot could have easily blathered some corporate line about liability, and closed their doors to those seeking shelter from the storm.  Instead, they did a great thing for people in their neighborhood, including Erie Basin in Red Hook.  That deserved some recognition.

I had three dozen custom tee shirts made.  On them was imprinted the legend, “Hurricane Sandy – October 29, 2012 – Heroes of Erie Basin” at the top, followed by drawings of the two tugboats done by a professional artist, and at the bottom, “The Crews of the Tugs Jill Reinauer and Kristy Ann Reinauer, and Home Depot, Gowanus, Brooklyn”.  On my next crew change, I went to the Home Depot, saw the assistant manager, and gave him half the tee shirts to distribute to those deserving however he saw fit.  He was overwhelmed.  He had a co-worker hold a shirt while he took a cell phone photo and sent it to his manager at home.  I gave the other half to the tugboat crews who moved the cars in the wind, rain and rising water.  A few months later, I started a kitchen remodeling project and ordered $2,400 worth of cabinets from Home Depot, which, pre-Sandy, I would have bought somewhere else.

Talking about tropical cyclones in Jeju: IWTC-VIII

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I spent last week on Jeju Island, South Korea, for the Eighth International Workshop on Tropical Cyclones (IWTC-VIII) organized by the World Meteorological Organization (WMO). Every four years, the WMO convenes this meeting, which gets together forecasters and researchers from all over the world to review the last four years’ advances in the science of tropical cyclones (also known as hurricanes, typhoons etc.). It’s an invitation-only meeting, which reflects (or maybe is one of the causes of) the fact that tropical cyclone experts are a close-knit club. I had never been invited before, which I took to mean that I was not really part of the club. I guess I am now.

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View east along the south coast of Jeju Island, near Jungmun Beach. In the foreground are basalt columns formed by rapid cooling of lava.

In the months before the meeting, the scientists involved put together a report to the WMO summarizing the advances since the last meeting in both basic science and operational forecasting practices. The structure of the meeting reflects the structure of the report. There are five overarching topics, each of which is a chapter, and a session of the meeting: 1. Motion; 2. Cyclogenesis, intensity and intensity change; 3. Communication and effective warning systems; 4. Structure and structure change; 5. Beyond synoptic timescales. Each topic has multiple subtopics, each subtopic has a “rapporteur” (or sometimes two) who led a team of people in the writing of their part of the report; the overall topic has a “topic chair” who organizes all of the subtopic reports and writes an introduction to the whole chapter.

I was the topic chair for topic 5, “Beyond synoptic time scales”. The word “synoptic” here refers to the time scale of a typical tropical cyclone forecast, a few days. The subtopics were climate change, seasonal forecasting, and intraseasonal forecasting – in that order, decreasing the time horizon sequentially.Seasonal forecasts are forecasts of overall tropical cyclone activity (with no details about specific storms on specific dates) for a particular region, made months in advance. The most important phenomenon that controls TCs on this time scale and makes the forecasts possible is El Nino. The “intraseasonal” time scale, also known as “subseasonal”, covers everything shorter than that, but longer than the range of a typical weather forecast. So, about 10 days to a month or two. On this time scale, the most important single phenomenon (though not the only one) modulating TC activity is the Madden-Julian oscillation, or MJO (see also here, here, and here).

Although I wasn’t at previous IWTCs, my sense is that at the last few, climate change has been a contentious topic.  Around 2005, Katrina and the hyperactive Atlantic season of that year, combined with a couple of high-profile papers showing increasing trends in various measures of TC activity, caused a dramatic increase in the volume of research being done on the links between climate and TCs (and in the number of researchers doing it). Combined with some historical cultural differences between TC experts and climate scientists, this led to some growing pains in the field in the mid-late 2000s. A lot of that has been sorted out now. Not that we know everything or that everyone agrees on the fundamentals – far from it – but the field has advanced rapidly in a decade, and a lot of the early contention has shaken out. It’s much clearer what we know and what we don’t. So this part of the meeting, and the report, while not without debate, was actually relatively placid.

In my view the most exciting new developments have been in the intraseasonal arena. Just a few years ago – certainly a decade ago – weather forecast models could not predict the MJO to save their lives. The best ones have become dramatically better at it, and now show skill in MJO prediction out to as long as 4 weeks’ lead time. Since the MJO influences tropical cyclones, this – combined with broader overall improvement in the models – makes new kinds of forecasts possible, well beyond the 5-day time frame of current tropical cyclone forecasts.

Forecasts in this range, let’s say a week to 2-3 weeks, are just barely starting to come into view. They exist still mostly in research mode, and are mostly not yet issued to the public. There are a few exceptions; an example is the NOAA CPC Global Tropics Hazards and Benefits Outlook, a “climate-like” product which defines large areas in which things could happen in the next two weeks. Other, more weather forecast – like products are clearly possible, such as long-range forecasts of the track and intensity of a specific storm that are produced several days before it has formed (currently, no agency issues public track and intensity forecasts for a tropical cyclone before it actually exists) – such forecasts would not be highly accurate, but could give some indication of a threat to a broad region ten, or even 15-20 days in advance. The science and technology now exist, since just recently, to issue products with some skill in this range. But forecasters are conservative. Before they’ll issue such products, they need time to understand how good or bad these forecasts are, and to learn how to communicate them effectively so that users of the forecasts grasp the uncertainties.

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Typhoon Hagupit on December 4, 2014. Day-night visible image from the VIIRS sensor on the NPOESS satellite, from the CIRA TC web page.

Meanwhile, during the whole conference, Typhoon Hagupit was drawing closer to the Philippines. It was quite a fearsome storm at midweek, reaching Super Typhoon status. We had regular forecast briefings during the latter part of the conference, from the Japanese and Korean Meteorological Agencies. Thankfully the storm weakened quite a bit before landfall. Between that and better evacuations, it looks so far like it won’t be near the disaster that Haiyan was last year. But Hagpuit provided a constant vivid reminder, as one presenter said at the start of this talk, of “why we do this”.