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Scientist. Pilot. Formerly worked for the Government.

Maysak: much weaker landfall, impact on Philippines forecast less than $150 Million

maysak_thu

Very different impact forecast than yesterday, and yet another good example of the complexity of forecasting the impacts of natural hazards.  The landfall intensity has decreased from 85 knots to 65 knots – a 25% decrease in wind speed.  But the impact forecast dropped by nearly 90% to from over a Billion dollars to about $130 Million!  Why?  Because the amount of force the wind creates (the “dynamic pressure”) is related to the square of the wind speed, not the wind speed itself.  So the pressure from a 65 knot wind is only 58% of the pressure of an 85 knot wind.  But it’s a bit more complex than that, and damage relates to a number of complex factors that ends up being a higher power factor of the wind difference above a threshold.  So for a typical house, an 85kt wind might cause 16% damage, whereas a 65 knot wind would only cause 4% damage.  Another factor in this case is that the swath of damaging winds is smaller, and misses the densely populated areas near the Capital, Manila.  Put all that together, and while the track doesn’t look that different, and the winds are a bit less, the damage forecast is dramatically different.  Which is a good thing – the Philippines really doesn’t need another disaster given the last few years of Typhoons and earthquakes.

Maysak continues towards Philippines; Damage near $1 Billion still predicted

Maysak is not as intense as yesterday, but is still an impressive and powerful storm at 130kts/150mph/240kph:
maysak_wed_am

Forecast track has been pretty steady to hit the northern Philippines island of Luzon in a bit over three days:
maysak_wed

On this track, and using the JTWC forecast intensity at landfall of 85 knots, the storm could cause upwards of $1 Billion dollars in damage.  For perspective, that is about 0.3% of GDP, or the equivalent of a $40 Billion dollar storm hitting the US.  That is about the same damage as Hurricane Ike, which hit Texas in 2008, and is the third most expensive storm in US history.  The Philippines has been hit be several intense storms the last few years, such as Haiyan in 2013 and Bopha in 2012 – in fact they have had 6 disasters that, in GDP equivalents, would have been worse than Hurricane Andrew, just since 2010.  Bad Luck, or changing climate ?

Typhoon Maysak

Typhoon Maysak  (WP042015) is a very powerful, 140kt/160mph/260kph storm, currently south of Guam.  The Joint Typhoon Warning Center (JTWC) forecast track has it headed towards the northern Philippines:
maysak

On this track it would make landfall with winds at around 95kts/180kph, and cause between $500 Million and a Billion dollars in damage.  Last year JTWC’s intensity forecasts were not so great.  The objective models, and the Japan Meteorological Agency Ensemble (pink line) forecasts also show the storm striking the northern Philippines:
maysak_tks

The JMA Ensemble forecast has a  weaker storm, only 80 knots at landfall.  80 vs 95 may not seem as much, but an 80knot wind only has 70% of the energy of a 95 knot wind; big difference in damage.

Typhoon Higos (WP022015) in the North Pacific

Typhoon Higos is moving through the North West Pacific, in the big blank area between Guam and Wake Island:
higos

Nothing in the way, no damage forecast.  It’s a bit unusual for this time of year, but our good records of the Pacific only go back to the 1940’s, so it’s a bit hard to draw any conclusions from this.  This is the second North West Pacific storm (the WP022015 designation is the Joint Typhoon Warning Center tracking number – WP is West Pacific, 02 is the second storm, 2015 the year).

Snow means it’s warmer???

Not a lot of major disasters lately (although the small ones obviously hurt the folks in the way), and I’ve been busy doing a climate analysis project for the UK DFID. The real time site always has the latest earthquakes, volcanoes, and hurricanes/tropical cyclones situation.

The recent snowstorms across the US have triggered the usual snarky comments from those who don’t accept the *fact* of anthropogenic climate change.  But anyone who has lived in the far north or arctic knows that it has to be “warm” to get snow.
Huh?
You read that right, but “warm” is a relative term.  Take a look at this graph, from Danial Cobb, science officer of the NWS/WFO in Caribou, Maine (click to embiggen):
snowratio

Not the biggest/fluffiest/deepest snow rates will be between -14 and -18 C.  OK, -16C (3.2F for you folks stuck in the 17th Century) isn’t warm if you are from the south, but it’s actually pretty “warm” for places that routinely see temperatures below zero F.  The other big issue is that the colder it gets, the less moisture the air can hold.  So colder air is naturally drier, and can’t hold as much snow.  So the “optimum” for both quantity and depth is somewhere between freezing and zero F.  Ironically, in the arctic, to get a blizzard, it has to warm up!  The other big issue is transporting moist air into the colder areas.  The models have predicted (and we seem to be seeing) more “latitudinal” (eg north-south) flow, which would cause more stormy and snowy weather – even though the overall temperatures are actually “higher” in relative terms.

Climate change is a very complex phenomena, intermixing human and natural changes and activities.  Far too many people on both sides of the debate do the discussion a disservice by simplistic, apocalyptic explanations.

WP01 (Mekkhala) Makes landfall on the Philippines; stronger than expected

Typhoon Mekkhala (WP012015) is making landfall on the Philippines as a minimal Typhoon.  The current forecast track/intensity, using the Joint Typhoon Warning Center (JTWC) forecast and my Taru model, is below.  JTWC continues the trend last year of not doing a great job on intensity forecasts – Thursday the landfall intensity was only forecast as 50 knots, but the storm is significantly stronger today, at 70 knots.

wp01_fri

Estimated impacts are around $150 Million USD, although the misery will be out of proportion to that due to the ongoing recovery from last year’s storms.

Mekkhala has forced the Holy Father to cut short his papal visit, barely making it out ahead of the storm. Unfortunately, there was a fatality when some scaffolding near the stage collapsed, and an airplane carrying government officials overshot the runway and ended up in a ditch just after he left.  I’ll not comment on the theological implications of that.

Typhoon headed towards Philippines

We already have the first storm of the 2015 season, and it’s headed towards the same place many of the storms hit last year: the central and northern Philippines:
wp01_thu

Using the Joint Typhoon Center track, damage is forecast to be in the $40 Million range, with the storm peaking as a 50 knot tropical storm, and passing south of Manila as a minimal tropical storm.  All in all shouldn’t be too bad, but there are still a lot of people reeling from last year so this is not exactly a welcome system.

Gonzalo closes in on Bermuda

Gonzalo will pass over or very close to Bermuda today.  Here’s the visual band view as the sun rises this morning:
govis2

The forecast tracks are all tightly cluster with the peak winds passing directly over the island.  Here is the forecast wind swath, using the NHC forecast track and my Taru wind model:
gomph

Slight wobbles will matter a lot – and because wind damage is relative to the cube of the wind speed, even 10mph difference can mean a lot.  On this track we would expect 110 to 120mph winds over the islands.  That is almost identical to Hurricane Fabian in 2003.  Fabian caused over $300 Million USD in damage in 2003; we should expect at least as much from this storm unless we get a lucky wobble.