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Timeline: How we got here …

Timeline: How we got here…

How an idea became a dataset, which led to a citizen science project.

The road to this point – having nearly 300,000 image being analyzed by hundreds of helpers – was a long one. This was not foreseen when it all began. The following is a detailed timeline that brought us here:

  • 2005/12 – R. Murnane [RPI]  (on behalf of J. Kossin [then at UW/CIMSS]) contacts NCDC with a request for satellite imagery of hurricanes. None existed. Customer service works with K. Knapp, a new dataset might be possible.
  • 2006/01 – K. Knapp and J. Kossin iterate on dataset development, working on what would become the Hurricane Satellite (HURSAT) dataset. Storm positions and intensities provided by C. Schreck [then a student at U. Albany]
  • 2006/11 – Participants at a global meeting of tropical cyclone researchers and forecasters (IWTC-VI) recommend creation of a central collection of tropical cyclone best track data.
  • 2007/01 – J. Kossin’s paper on TC trends based on an objective analysis of HURSAT is accepted by the Geophysical Research Letters
  • 2007/01 – K. Knapp’s paper describing the HURSAT dataset is accepted for publication in the Journal of Applied Remote Sensing.
  • 2007/07- K. Knapp spends summer attempting to update HURSAT using new track data internally (to support routine production) working with C. Schreck. Numerous issues involving how to obtain global data from individual sources are found.
  • 2007/10 – A team at NCDC meets to discuss potentially creating a centralized, global collection of best track data at NCDC – what would become IBTrACS. (Initially it was called the NGTCS: NCDC Global Tropical Cyclone Stewardship)
  • 2007/12 – The NCDC Team contacts RSMCs and other best track sources with regard to a new global collection. Positive response is received by all.
  • 2008/09 – First public release of IBTrACS announced to public.
  • Unknown – Somewhere during this time (2007-2010), the idea of using a team of scientists to perform historical analysis is floated. Many are included on the discussions.
  • 2011/01 – P Hennon presents a poster at Annual AMS suggesting that crowd sourcing of imagery might lead to fast and accurate reanalysis of satellite imagery.
  • 2011/03 – S. Lynn of Zooniverse visits NCDC to discuss potential crowd sourcing projects. While initial discussions focused on keying surface observations, there was much interest in the idea of people investigating hurricane imagery.
  • 2011/09 – Selection of our project as a candidate for development by Zooniverse.
  • 2012/09 – goes public. More than 40,000 classifications in the first 10 days!
  • 2014/10 – Cyclone Center paper published in the Bulletin of AMS. Coauthors include some citizen scientists.
  • 2016/10 – Cyclone center paper published in the Monthly Weather Review. It shows initial results of storm type accuracy.
  • 2017/03 – Here we are. Nearly 650,000 classifications later and still going strong!

Your Classifications Are Making A Difference

Cyclone Center was the 14th project hosted by Zooniverse when it was launched in September of 2012 and only the second that was based on weather or climate data.  As we come up on our 4th birthday, we’d like share what we’ve learned so far and how your classifications over the next few months will lead to even more exciting findings.


Typhoon Nabi (2005) was a powerful storm that our classifiers successfully completed analyzing.

The reason for Cyclone Center is simple.  Tropical cyclones generally develop over remote areas of the ocean, where there are few if any direct observations of them.  It is vitally important that we know how strong these storms are for societal (e.g. warnings, evacuations, protecting life and property) as well as scientific (e.g. are storms getting stronger with climate change?) reasons.  Since storms are typically not directly measured, scientists use images of them to estimate the wind speed.  Unfortunately, although the algorithm used around the world is basically the same, it is subjective and significant disagreement has crept into the historical record.  Cyclone Center uses a special set of satellite images and classifications from you to determine a more consistent, and thus better, estimate of tropical cyclone winds.

Over the last four years, we have learned much and have had a number of notable accomplishments with your help: Read More…

Joaquin: Classifying Shear Storms in Cyclone Center

Tropical Storm Joaquin is moving slowly over warm North Atlantic waters this evening.  If atmospheric conditions were ideal, Joaquin would be well on his way to becoming a hurricane.  Instead, he is struggling to develop because the atmospheric winds are creating strong “shear” which displaces the energy source of the storm away from the center.  Watch the animated image below:

Read More…

Participate in Real Science – Help Classify Tropical Cyclone Winds


Cyclone Center, now in its third year, is a website that allows citizen scientists like you to help meteorologists like us determine the maximum wind speed (or “intensity”) of historical global tropical cyclones.   We need your help to complete this ambitious project.

Why am I needed?

Cyclone Center WebpageFirst,  there are way too many images (nearly 300,000!) for us to do it alone!  Second, your responses as a group are almost always just as good as an expert!  And third, there are disagreements in the historical record that must be addressed.    For instance, there are studies in published literature that suggest that typhoon activity is both increasing and decreasing in the western Pacific Ocean. Clearly both cannot be true!

Why are there questions about tropical cyclone data? 

Read More…

Spawns of El Nino? Hurricanes Iselle and Julio Aim For Hawaii

Cyclone Center is tracking two storms as we classify this afternoon.

It has been quite a remarkable week in the eastern and central Pacific that has culminated in two hurricanes taking aim at the Hawaiian Islands today.  Hurricane Iselle has shown herself to be quite resilient as she has maintained her hurricane strength despite moving over cooler ocean waters.  Hurricane warnings are out for the big island as residents prepare for a significant event.  Meanwhile, Hurricane Julio is following close behind, continuing to intensify despite his movement over cooler waters.  The graphic below from the Central Pacific Hurricane Center shows the likelihood of significant winds over the next few days in the islands: Read More…

Kulab says “Please Classify Me!”

Not much has been happening in recent weeks in the tropics (with the notable exception of the extreme western Pacific), so allow me to try generate some fake excitement by highlighting one of our four featured storms – KULAB.  Why Kulab?   Read More…

A Quiet Hurricane Season in the Atlantic?

The official start of the hurricane season in the North Atlantic was June 1 and most experts are predicting a relatively quiet season, pointing to relatively cool water temperatures in place and a developing El Nino in the Pacific.   El Nino can be thought of as a substantial warming of ocean water in the central and/or eastern Pacific which in turn alters global weather patterns.  Atlantic hurricanes typically encounter more hostile atmospheric conditions during El Nino events, limiting their potential to develop and strengthen.  Most of the inactive seasons in the Atlantic over the past 20 years have occurred during El Nino events. Read More…

Featured Storm – Hurricane Emily (2005)

By the time Emily made her appearance in the second week of July, the 2005 Atlantic season had already produced four named storms (tropical storm strength or better) and was on its way to a record breaking performance.  So it was hard to stand out from the crowd that year, but Emily sure did.

Emily formed the way many of the strongest tropical cyclones do in the Atlantic – as a tropical “wave” or disturbance that left the coastline of Africa on July 6.  She struggled at first to get her act together, as dry air penetrated her core and the upper level winds in the area kept trying to rip her apart.  But Emily kept it together long enough to obtain tropical storm status on July 11.  But the fun was just beginning.

Hurricane Emily (2005)

Hurricane Emily readies herself for the final plunge into Mexico

The next day, the “steering winds”, or the upper level winds in the atmosphere that push the system along, increased in intensity.  Emily’s forward speed increased from a sluggish 10 kt. to a quite respectable 17 kt.  Although this initially made Emily’s environment less favorable,  recon planes noticed her winds at the surface unexpectedly began to increase.  Everything seemed to fall into place and just 2 days later Emily was a major Category-4 hurricane with maximum winds near 115 kt.

As Emily passed south of Jamaica, the records began to fall.  She became the earliest (since records began in the 19th century)  tropical cyclone to reach Category-5 status.  Furthermore, Emily to this day is the only known storm to ever achieve Cat-5 intensity in the month of July in the Atlantic.

Fortunately, Emily spent most of her time over the ocean when she was strongest.   But she did pass directly over Grenada, Cozumel Mexico, and northeastern Mexico near San Fernando.  Damage was unexpectedly light in the Yucatan, with mostly minor wind damage and flooding reported.  Northern Mexico appeared to receive the worst of the storm, with 90,000 people driven from their homes and thousands of buildings destroyed.  Miraculously only 6 deaths were reported from the storm, 4 in Jamaica when a car was pushed over a cliff from flood waters.

Go to Cyclone Center today and start classifying Hurricane Emily.  She was truly a memorable one.  Much of the information given here and more can be found in the U.S. National Hurricane Center tropical cyclone report for Emily.

– Chris Hennon is part of the Cyclone Center Science Team and Associate Professor of Atmospheric Sciences at the University of North Carolina at Asheville

A Better Cyclone Center

Cyclone Center has recorded over 210,000 classifications from citizen scientists around the world since its launch in September 2012.  But we’re not resting on our laurels; the site has undergone significant changes that we think will make your experience classifying storms even  more rewarding. Highlights of the new site include:

1. Targeted storm choices.  Choose your favorite storm to classify from a list of four storms that we’d like you to focus on.  These storms will change frequently as you help us complete each one.  Featured in the early sets of storms will be at least one storm from the historic 2005 Atlantic hurricane season, including Hurricanes Katrina and Wilma.  Or, if you’re feeling adventurous, click the “Classify a random storm” button and get a mystery storm!

New selection menu for Cyclone Center

New selection menu for Cyclone Center

2. Inline classification guidance.  Gone are the days of clicking on question marks to get help.  For each step in the process, you will be shown information on how to best answer the question.  Even though you have been doing great, we think this will give you more confidence in what you are doing and hopefully inspire you to do more!

3. Improved tutorial.  Haven’t classified in a few weeks?  Now you can access our improved tutorial at any time for a refresher.

4. More questions to answer.  For each storm, go beyond the “choose the closest picture” to answer a couple of more questions like where the center of the storm is or how cold the clouds are around the eye.  This used to be called “Detailed Classification”; your responses help us to better pinpoint how strong the storms are.

5. Real time feedback on your classification.  Now instead of waiting for 6 images to see the “Storm Stats” page, you will immediately go there after your first image.  Now available on this much improved page is the storm track, the location of the storm you just classified, and our estimate of the wind speed of the storm based on your answers.  

Real time feedback

Real time feedback on your work is now given after each image

6. Upgraded Talk forum.  “Talk” is how you can discuss interesting storms with others or us.  The upgraded version allows for better searching and highlights more of the interesting discussions going on between other citizen scientists.

7. Better connections to social media.  Direct links to Facebook and Twitter are now available on every storm on the home page.  Click and discuss storms with your social communities or invite others to participate!

Log in to Cyclone Center today and give the new version a try – we think you’ll like the changes.  As always, please let us know what you think by commenting on this blog entry or through Talk!

– Chris Hennon is part of the Cyclone Center Science Team and Associate Professor of Atmospheric Sciences at the University of North Carolina at Asheville

Seasonal Tropical Cyclone Forecasts Are Coming In – But Are They Worth It?

Citizen scientists working on Cyclone Center are working with a few thousand tropical cyclones which have developed since 1978.  Beginning just a few years later, Dr. Bill Gray at Colorado State University (CSU) first began issuing forecasts for the number of tropical cyclones that will develop in the Atlantic Ocean for the upcoming Atlantic season (June 1 – November 30 each year).  Since that time, several other groups, including the U.S. National Oceanic and Atmospheric Administration (NOAA), have also developed similar techniques to predict seasonal activity.  With the official start of the Atlantic season just a couple of weeks away, this year’s predictions are in.

Hurricane Andrew

Hurricane Andrew, a devastating Category-5 storm, occurred during an extremely quiet Atlantic hurricane season.

The CSU forecast, issued in April of this year,  predicts 18 named storms (those achieving at least Tropical Storm strength), 9 hurricanes, and 4 major hurricanes (Saffir-Simpson Category 3 or higher).  This is well above the long-term average for the Atlantic.  The NOAA forecast, which relies on similar parameters to predict activity (e.g. warm ocean temperatures, El Nino phase),  puts the chances of an active season at 70%.  Groups in other parts of the world also produce seasonal forecasts for their own region.  For example, the Bureau of Meteorology in Australia issues a national as well as regional seasonal outlooks.   Recently, other groups such as the United Kingdom Met Office have begun issuing “dynamical” forecasts, which explicitly count tropical cyclone-like features in weather models rather than relating environmental conditions to past activity.

Seasonal forecasts receive quite a bit of publicity, despite questions about their skill and usefulness.    Statistical schemes such as the CSU forecast, rely on past connections between environmental factors and TC activity.  They fail especially in predicting extreme seasons, such as the 1995 or 2005 Atlantic seasons, because the models just don’t know about hyperactive years like that.   Dynamical predictions, which theoretically can predict record breaking years since they do not rely on past seasons, have been shown to have better predictive skill than statistical techniques for seasonal TC prediction.

But even if a model were 100% accurate, would it really make a difference?  The majority of systems that do develop into tropical cyclones do not affect land.  Predictions of landfall are made by several groups but have not shown any skill so far.  For any given location of coastline, the chances of a TC impact in any given year are very small.  So if a homeowner hears that the upcoming season will be active, should any action be taken?  Does it really matter if we’re going to get 12 storms this year or 11?  Remember that some of the most devastating hurricane events in U.S. history, such as Andrew in 1992,, occurred during inactive seasons.  In the end, how do seasonal forecasts help society?

One could argue that any publicity that gets people to assess their readiness is good – but I think that most will not do anything.   Perhaps more effort should be invested in determining how the nature of tropical cyclones will change in our warming world.  Cyclone Center is going to provide researchers with new data that will help determine if and by how much the nature of global tropical cyclone activity has been recently changing.  With stronger tropical cyclones predicted in the Atlantic and other parts of the world – along with rising sea levels – time and energy is better spent developing plans for mitigation for the big ones rather than issuing forecasts with little or no value for coastal residents.

– Chris Hennon is part of the Cyclone Center Science Team and Associate Professor of Atmospheric Sciences at the University of North Carolina at Asheville