TempRisk 4.0 Release: Change Guide October, 2012 TempRisk 4.0: Innovative, Intuitive TempRisk 4.0 is our most innovative product to date. Driven by a new empirical forecast model, this version has significantly improved skill above climatology and is competitive with the ECMWF weekly forecasts -- especially out to weeks 2-4. The improved accuracy is the result of a genetic algorithm -- a selection process that intelligently combines the most important signals for a specific region and forecast window. TempRisk s new empirical forecast model is capable of evaluating thousands of weather signals to find the optimal signal combinations. These combinations are not always a product of the two or three signals with the highest probabilities for cold or warm. But rather, the optimal combination can be from weak signals that produce a strong response only when combined. While this empirical forecast model is the standout improvement in our winter 2012/13 release, TempRisk 4.0 also includes intuitive interface enhancements, workflow improvements and innovative analysis tools. We have added multiple variables to our daily analysis including MJO, OLR, snow cover, sea surface temperature, surface air temperature and the seasonally adjusted 10mb air temperature and 50mb air temperature. With this additional data, TempRisk now utilizes a database 10-times larger than ever before. In this version, we introduce the new TempRisk Almanac page as the primary interface to the historical weather patterns and their relationships to subsequent regional extreme temperature events. This page is your go-to source for the analysis of specifically quantified synoptic patterns. In addition, we redesigned the TempRisk Indices, now showing the HeatRisk and ColdRisk events on the same page. The redesign includes sorting sliders, moving day averages and the ability to overlay more than one region at the same time. The TempRisk Dashboard and the TempRisk Scorecard have a new look with HeatRisk and ColdRisk events on the same page, enhancing the daily usability of these accessible forecast guides. At EarthRisk, we think you ll find TempRisk 4.0 to be our most innovative and intuitive version to date. TempRisk 4.0 used 25 8-core processors (200 total cores) to parallel process for 48 hours.. That is a total of 9,600 computation hours, or 400 computation days, or 1.1 years of computation on a single core. The total number of models fit were 3,348 (9 regions x 6 3-month-seasons for Winter x 2 TempRisk types x 31 forecast day lead windows). [1]
What s new under the hood? A look at TempRisk s new methodology One of the largest improvements to TempRisk 4.0 is our new empirical forecast model that can intelligently combine the most important signals for a specific region and forecast window. TempRisk 4.0 s empirical forecast model is a selection algorithm that uses the best possible combination of synoptic-scale weather patterns as precursors to regional extreme temperature events, and systematically reduces false alarm rates associated with redundant and non-informative signals. Imagine one physical pattern that is represented across three different signals (perhaps a pressure, temperature, and wind signal). It would be preferable to only include one of them as to to not over-weight the physical pattern. Because TempRisk has hundreds of signals, we have employed a method to intelligently identify and eliminate signals that are redundant, while retaining highly predictive signals. We were able to implement such a method to help us identify the best set of signals for every region, lead time, and HeatRisk/ColdRisk combination. Filtering signals is only part of the improvement, however. We also created a way to finely tune the signal combination process to better capture the non-linearities of the atmosphere. In order to do this we used a genetic algorithm to tune our model on a series of out-of-sample data sets. TempRisk 4.0 s statistical forecast model is an advanced algorithmic selection process. A genetic algorithm is an algorithm used in optimization problems. It starts with a number of guesses of the solution to the problem, evaluates them, keeps the good solutions, discards the bad solution, and creates new solutions through combinations and mutations of the good solutions. It is survival of the fittest applied to optimization, hence the name genetic algorithm. (Click to learn more..) [2]
TempRisk 4.0 Almanac (Professional Subscription tier) We created a new interface for the TempRisk Almanac that is a that is a one stop shop for displaying patterns and their relationships with subsequent regional extreme temperature events. The new Almanac Page provides the capability to look at all important patterns, allowing for physical progressions to the subsequent events. From this page, users have the ability to dive right into the traditional signal map and signal information and see the strength of the pattern occurrence over time. 1 2 3 4 5 7 6 1. The TempRisk Almanac is the source of historical analysis of pattern occurrence and corresponding events. 2. The search options allow users to view which patterns are significant for HeatRisk and ColdRisk for the corresponding region, season, lead window, variable and initialization date. 3. The top bar chart illustrates the number of events occurring per decade. Users can download the dates of this decadal chart. 4. By clicking on the decadal chart, the site will direct users to the traditional signal map and signal information where they can view the signal strength of the pattern occurrence over time. 5. The Almanac shows the historical probability of a HeatRisk or ColdRisk event at various lead windows across six standard deviation thresholds: -1.75, -1.00, -.50,.50, 1.00, 1.75 6. Blue and red bars indicate the distribution of HeatRisk and ColdRisk events. 7. The patterns are ranked according to which is the most significant for the period. For each query, the pattern image at the top of the page is the most significant for the region, season and lead window that are selected. [3]
TempRisk 4.0 Indices We have completely redesigned the TempRisk Indices page with increased functionality and usability. The indices graph has new capabilities with added sorting and slider options. This new page allows users the ability to overlay more than one region at the same time, and to view HeatRisk and ColdRisk on the same graph. 1 2 3 4 5 6 1. The TempRisk Indices page has an entirely new look with improved visuals and functionality. 2. Users can choose among 1, 5, 7 and 10 moving-day averages. 3. Users have the ability to overlay more than one region at the same time. 4. HeatRisk and ColdRisk display on the same graph. 5. When the index is less than 25% or more than 75%, the data points are colored according to the region color. When the index is between 25.1% and 74.9% the data points appear opaque. 6. The interface has new sorting sliders to capture dates. [4]
TempRisk 4.0 Dashboard The new TempRIsk 4.0 Dashboard page features TempRisk Scorecards with both HeatRisk and ColdRIsk probabilities on the same page. The dashboard now uses bars to represent the HeatRisk & ColdRisk probability with the corresponding lead time window. (Days 1-40) 1 2 3 4 1. The TempRisk 4.0 Scorecard features HeatRisk and ColdRisk events on the same page. The black HeatRisk and ColdRisk lines indicate Climatology (25%). 2. Each blue or red color bar indicates the HeatRisk or ColdRisk probability for each lead time window. 3. The TempRisk 4.0 Dashboard thumbnail images are distributed to customers on a daily basis to show the TempRisk Forecast for all regions subscribed to. 4. We have added a legend that shows the maximum and minimum HeatRisk and ColdRisk signal, and the corresponding lead window [5]
TempRisk 4.0 Scorecard The TempRisk Scorecard has a completely new look with HeatRisk and ColdRIsk events now on the same page. We have added Prev and Next buttons to simplify scrolling from one initialization date to the next, making it easier to see hot and cold trends. Each color bar represents the HeatRisk and ColdRisk probability to the corresponding lead time window. When you hover over a bar a tool tip provides details on lead time, hit rate and target date. 4 2 1 3 5 1. The TempRisk 4.0 Scorecard now shows both HeatRisk and ColdRisk events on the same page. 2. Each color bar represents the HeatRisk & ColdRisk probability with the corresponding lead time window. When you hover over the bar, a pop-up gives details on lead time window, hit rate and target date. 3. The climatology lines for HeatRisk (red) and ColdRisk (blue) are at 25%. 4. The Prev and Next buttons on each side of the Init Date allow the user to scroll through days of data. 5. At the bottom of the page, Data Source: Preliminary indicates that the data is the initial data from GFS and MJO. Once NCEP/NCAR Reanalysis Data populates the site, this banner reads Data Source: Final. [6]