Climate change may also be driving the observed trend of increasing
hurricane intensity as well as the observed trend of more rapidly intensifying hurricanes.
Not exact matches
No one knows exactly what happens in the cradle of a
hurricane but we do know that often the smallest of factors can act
as a catalyst to a storm that builds in
intensity as it crosses the Atlantic and crashes ashore in North America.
The
intensity of
Hurricane Maria, which made landfall on Puerto Rico
as a Category 4 storm on September 20, was part of why it was so devastating to the island and its weak infrastructure, leaving Puerto Ricans in a humanitarian crisis.
The best historical analogue for a
hurricane that follows NHC's 5 pm EDT Friday track and intensity forecast for Irma may be Hurricane Donna of 1960, which tore through the Florida Keys just northeast of Marathon as a Category 4 storm with 140 m
hurricane that follows NHC's 5 pm EDT Friday track and
intensity forecast for Irma may be
Hurricane Donna of 1960, which tore through the Florida Keys just northeast of Marathon as a Category 4 storm with 140 m
Hurricane Donna of 1960, which tore through the Florida Keys just northeast of Marathon
as a Category 4 storm with 140 mph winds.
Add extra shots
as needed to match the categorical
intensity of your particular
hurricane.
Scientists working to improve storm
intensity forecasting have identified a more accurate means of predicting a
hurricane's strength
as it approaches landfall, using sea temperature readings that they say will help forecasters better prepare communities for storm impacts in the face of sea - level rise caused by rising global temperatures.
Others, such
as a new microsatellite system aiming to improve measurements of
hurricane intensity and a highly anticipated new computer simulation that forecasts
hurricane paths and
intensities, are still in the calibration phase.
Powerful
hurricanes such
as Harvey, Irma and Maria are also providing a testing ground for new tools that scientists hope will save lives by improving forecasts in various ways, from narrowing a storm's future path to capturing swift changes in the
intensity of storm winds.
Still, he also cautions against the assumption that rainpower is the only factor impacting
hurricane intensity,
as not all the eyewall's rain falls directly down through the updraft.
Previously, researchers thought rain in the eyewall increased a
hurricane's
intensity,
as heat released from the condensing water added to the overall power of the storm.
But a reduction in the number and
intensity of large
hurricanes driving ocean waters on shore — such
as this month's
Hurricane Joaquin, seen, which reached category 4 strength — may also play a role by cooling sea - surface temperatures that fuel the growth of these monster storms, the team notes.
Even
as cities become more vulnerable to moderate storms, the
intensity of
hurricanes may increase dramatically, says Kerry Emanuel, a meteorologist at MIT.
Even
as Irma struck Florida, civil engineer Forrest Masters of the University of Florida in Gainesville, his students and collaborators traveled to the southern part of the state to study the
intensity and variation in the
hurricane's winds.
There is, however, limited evidence from a relatively short time period that storm strength is increasing, such
as the Emanuel (2005) «power dissipation index» of
hurricane intensity.
Building on methods they used to assess the impact of
hurricanes such
as Katrina, Gustav, and Rita on forests and tree mortality, scientists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have produced a rapid mapping of the disturbance
intensity across Puerto Rico's forests with the help of Google Earth Engine.
Climate models suggest that
hurricane intensity should increase
as the world warms, and that the most intense storms will become a bigger proportion of the total.
After a natural disaster, such
as a high
intensity hurricane, tens of thousands could be displaced to areas ill - equipped to handle the sudden influx of people for an unknown period of time.
The following figure, for example, represents an assessment of what will happen to the number and
intensity of
hurricanes as the climate warms.
Perhaps worldwide melting of glaciers by global warming will increase the incidence of volcanic eruptions and earthquakes,
as well
as increasing the
intensity of
hurricanes.
Several recent studies such
as Emanuel (2005 — previously discussed here) and Hoyos et al (2006 — previously discussed here) have emphasized the role of increasing tropical sea surface temperatures (SSTs) on recent increases in
hurricane intensities, both globally and for the Atlantic.
With regard to Williams answer to Terry (# 34), I believe that Terry is correct that it is temperature differences that are fundamental, and not, for the most part, the temperature itself,
as Emanuel has discussed in a series of important papers on the maximum
intensity that
hurricanes can attain.
The current Landsea / Trenberth / Emanuel discussion has been parsed by many to mean that Landsea claims that the number of
hurricanes is constant, and Trenberth is claiming that their
intensity should increase
as global warming heats the ocean surface.
So the policy idea is to greatly reduce GHGs so
as to reduce future
hurricane intensity (& use savings from those reductions to storm - proof buildings).
The evolution of the
hurricanes is altered in some way by conditions other than SST (such
as humidity) in the various models because the resulting
intensity of the
hurricanes seems to be shifted somewhat surprisingly by a constant amount across all SSTs according to Figure 11.
As with the
intensity of
hurricanes, that's a tough, if not impossible, call.
As we have discussed elsewhere on this site, statistical measures that focus on trends in the strongest category storms, maximum
hurricane winds, and changes in minimum central pressures, suggest a systematic increase in the
intensities of those storms that form.
Furthermore, the fact is (
as shown in Figure 1) that
hurricane intensity has increased in recent decades
as SST has risen (at least in the North Atlantic for which trends are most reliable) and this prediction is based on fairly fundamental and robust thermodynamic arguments explored by Emanuel and others for decades now.
In a few short years, when the Arctic sea ice is totally absent during the summer months, and the water and air up there get hot (instead of being cold
as it was during the past 10,000 years or more), we have no idea what is going to happen to the weather and that includes any attempt to predict
intensities and frequencies of
hurricanes, which, in my opinion, is a non sequitur.
Why is Katrina used
as an example of
hurricane intensity, when it was documented
as only a Category 3
hurricane (albeit with a large storm surge)?
It's important to remember that in 2006, both sides in the
hurricane - climate argument were awaiting Kossin's paper and saw it
as a first attempt by a neutral arbiter to come in and reanalyze the global
hurricane intensity data.
Which
hurricanes we will reduce in
intensity by our GHG reductions, we don't know, but since we care for all people, it doesn't matter which ones we help reduce,
as long
as we keep helping to reduce them.
The draft testimony says «Climate change is anticipated to alter the frequency, timing,
intensity, and duration of extreme weather events, such
as hurricanes and floods.»
As early as 1992 my Earth Day display on GW had a big hurricane on it, with mention of GW contributing to hurricane intensity AND frequenc
As early
as 1992 my Earth Day display on GW had a big hurricane on it, with mention of GW contributing to hurricane intensity AND frequenc
as 1992 my Earth Day display on GW had a big
hurricane on it, with mention of GW contributing to
hurricane intensity AND frequency.
Notably, issues such
as why a given
hurricane stalled or took a particular track (problems in dynamics) could not reliably be attributed to anthropogenic climate change, unlike
intensity (which is clearly related to the thermodynamic state of the atmosphere and oceans).
In this context, I used Kossin's study
as a peg to discuss just how contested the global
hurricane intensity records remain, especially in basins other than the Atlantic.
And,
as increase in ocean temperature lags increase in atmospheric temp., even if no AGW signal is yet visible in the
hurricane data, this may not mean very much in terms of the future impact of AGW on
hurricane intensity.
In following the course of projections for this storm, and then the burst of criticism about failed
intensity forecasts, I was brought back to the hours I spent with meteorologists at the National
Hurricane Center in September, 2004, as they tracked the course of Hurricane Ivan (shortly before I headed to Alabama to cover its landfall as a major hurricane; here's a narrated report I filed from
Hurricane Center in September, 2004,
as they tracked the course of
Hurricane Ivan (shortly before I headed to Alabama to cover its landfall as a major hurricane; here's a narrated report I filed from
Hurricane Ivan (shortly before I headed to Alabama to cover its landfall
as a major
hurricane; here's a narrated report I filed from
hurricane; here's a narrated report I filed from Mobile).
Furthermore, the paper clearly states that it doesn't address
hurricane intensity, but only the landfalling
hurricane record — and
as others have noted the landfalling
hurricane record doesn't really relate to the total
hurricane frequency.
Don Keiller —
as others have pointed out, that paper doesn't attempt to address the issue of the recent increase in Atlantic
hurricane intensity, or the ongoing increasing trend of increasing sea surface temperatures and atmospheric moisture content.
By 2100 the number of
hurricanes could drop by up to a third, but the average
intensity of the storm could increase by
as much
as 11 %.
Wind varies in
intensity and strength from a gentle breeze to a powerful and destructive storm, such
as a
hurricane or tornado.
Increased
intensity of
hurricanes as expected from rising sea surface temperatures 12.
Since
hurricane intensity and detection data is problematic
as one goes back in time, when reporting and observing practices were different than today, it is possible that we underestimated global
hurricane energy during the 1970s.
This means that Haiyan had warm water extending at least 100 meters deep to use
as fuel; this was a major factor that increased the
intensity of the
hurricane.
From what I know, theoretically it should be possible,
as the various climate geoengineering options proposed would have impacts precisely on the temperatures that drive
hurricane intensity;
Building on methods they used to assess the impact of
hurricanes such
as Katrina, Gustav, and Rita on forests and tree mortality, scientists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have produced a rapid mapping of the disturbance
intensity across Puerto Rico's forests with the help of Google Earth Engine.
While tropical
hurricane intensity is primarily driven by latent heat from warm sea surface temperatures, an extra-tropical storm is primarily driven by baroclinic processes (differences in the pressure gradient) such
as the gradient due to the contrast between the warm Gulf Stream and cold continental air mass.
(I) the past research completed related to
hurricane and typhoon development, track, and
intensity as reviewed by Working Groups I and II of the Intergovernmental Panel on Climate Change;
As NOAA explains «The ACE index is used to calculate the
intensity of the
hurricane season and is a function of the wind speed and duration of each tropical cyclone.»
There has been a substantial increase in most measures of Atlantic
hurricane activity since the early 1980s, the period during which high quality satellite data are available.20, 21,22 These include measures of
intensity, frequency, and duration
as well
as the number of strongest (Category 4 and 5) storms.