With winter rapidly approaching, we thought it was an ideal time for another high resolution elevation data import from the USGS 3D Elevation Program (3DEP). Although we regularly make updates to our elevation dataset as high resolution elevation data becomes increasingly available, the striking difference between the original lower resolution elevation data and the high resolution elevation data never gets old.
Check it out for yourself! Each of the images below are split images of the same location with the new high resolution elevation data on the left and the original lower resolution elevation data on the right. Move the slider to compare these two elevation datasets and see the difference high resolution elevation data makes!
Above: Split image of Long’s Peak in Rocky Mountain National Park, CO, with the shaded relief layer.
Above: Split image of the Sierras in California with MapBuilder Topo.
Above: Split image of Pyramid Peak near Aspen, CO with MapBuilder Topo and slope angle shading.
In addition to the above areas, other notable areas that were part of the latest high resolution elevation data import include:
El Dorado National Forest (south of Lake Tahoe), CA
All of southwest Colorado
Large portions of Rocky Mountain National Park
All of southeast New Mexico and large portions of northwest New Mexico
Northern Idaho
All of southwest Wyoming
All of Nebraska
All of southwest South Dakota
Large portions of Georgia
To see all the areas that currently have high resolution elevation data, check out this interactive coverage map.
Where can I see high resolution elevation data on CalTopo?
High resolution elevation data is available on the web, mobile, and desktop app. If you have a mobile subscription or higher, you can download it for offline use, allowing you to bring the high resolution elevation data with you into the backcountry.
Please keep in mind that currently CalTopo does not automatically update offline downloads when we do a new elevation data update. If you notice discrepancies between the online elevation data and your offline downloads, make sure to delete your old downloaded tiles and re-download the latest ones. More information on managing your offline downloads can be found in the Mobile App- Offline Useor CalTopo Desktop- Download and Sync sections of our user guide.
Limitations of high resolution elevation data
While high resolution elevation data is incredibly useful for backcountry travel, it should still not be relied on as a definitive source of truth. As is true of any map (even paper maps!), it is a model of the terrain (albeit a pretty good one!) but not the terrain itself. For a more in depth discussion, check out our blog post Maps and Tracks: Accuracy, Precision, and your Phone GPS (Part 1).
Always carefully assess and evaluate any terrain that you are traveling in, and confirm your observations instead of relying solely on maps. Seek professional instruction on how to travel safely in the backcountry- our partners at the American Mountain Guide Association and American Avalanche Association have some great resources to get you started.
Happy mapping!
https://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.png00Meghanhttps://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.pngMeghan2022-11-02 10:24:572022-11-02 10:35:46Latest High Resolution Elevation Data Updates- Bring on the Snow!
We are committed to continuing to grow our team and first responder functionality. Read on to hear from CalTopo founder Matt Jacobs about where team accounts are headed next.
The ground had been bare dirt just two weeks earlier, but by Dec 23, Tahoe was entrained in a series of winter storms. Fluctuating snow levels and ice formation had brought down trees all over the neighborhood, and I had just recovered from a 5-day power outage when the 7:30pm page went out for a missing 78-year-old male with dementia. I gathered my gear, spent a few minutes reading to my 4-year-old son – some things are difficult to negotiate away even in the face of an emergency – and was out the door.
At the far side of a condo complex, amongst kids’ snow forts and sled tracks, my teammate Kyle found a lone set of tracks in the snow. Instead of looping back like we expected, they proceeded out towards Martis Valley, and 40 minutes later we caught up to our missing person, cold, wet and immobilized by night. The initial urban search had given way to a backcountry winter environment that we were minimally equipped for, but a team of enthusiastic skiers was hot on our tail to pack down a route, and a snowmobile soon followed to get him the rest of the way to the ambulance. Driving home with a big smile under a moonless midnight sky, I texted my wife: “definitely saved a life today”. It had been a bumpy departure and I wanted her to know the cost had been worth it.
I’m sharing this story because for me personally and CalTopo as an organization, purpose matters. And although it matters, that purpose doesn’t always translate well to our daily tasks, the myriad moving parts needed to support a successful organization. On the search, all we did was follow some tracks through the snow – nothing particularly special. Supporting our ability to even be in that position was a long series of even-less-exciting support tasks. Purpose doesn’t change the oil in the team truck.
Much of what goes on behind the scenes at CalTopo is similarly mundane. Everyone who works here does so because they care about the product and believe in the mission. Still, the work is work, much like anywhere else. Over time, people leave and cultures change – across a long enough time horizon, will CalTopo remain a special place? And will our culture continue to carry the day for some of our user communities, if cold hard economics can’t?
I don’t know what the future will bring, but CalTopo can trace its origins directly to mapping issues on a large search in the Bay Area, and it’s important for me to ensure that community remains a core part of our user base. I also know that for all the agonizing it’s caused us, every time we’ve traded a bit of affordability in exchange for a better product, it’s proven to be the right decision. Five years ago we had just launched team accounts and had not yet started developing the app, and today remote planning and live tracking are critical to many teams’ workflows. I’d like our next five years to be at least as impactful as our last.
So, to get to the point: I’m excited to announce that we plan to invest more heavily in team and first responder functionality. In doing so our goal is to provide a higher quality product, grow adoption outside of the SAR community and ensure the longevity of those solutions even in the face of significant change within the company.
As a first step in that direction, we have already rolled out two new team-based collaboration features. First, all team accounts now support sub-teams, which give you finer-grained controls over how to structure your team. Want your specialty teams to have their own place to store maps? Sub-teams have you covered. Second, we are launching shared workspaces, which make map sharing between teams seamless. Commonly work with a neighboring agency or two? Setup a shared workspace with them and you can automatically share maps with each other. These are both live now, and more details will be coming soon.
CalTopo’s team account pricing has not changed since its initial rollout in 2017. Since then, we’ve learned some important lessons about our pricing model. There was, and continues to be, confusion around whether a 25 person account applies to teams of up to 25 people, or teams that want to cherry-pick 25 members. We’ve also struggled with the pricing cliff in between large size buckets, and with how to adapt our discounted volunteer SAR pricing to other use cases, such as hybrid paid / volunteer organizations.
So along with our renewed focus, we’re revising our team pricing model to be based on your choice of either organization size or population served, and not a self-selected size. We’re also adding a new, partial discount for organizations with a mix of volunteer and paid employees. And finally, team account signups are no longer self-serve: you’ll need to contact support and request a quote, so that we can ensure team sizes and discounts are appropriately matched to organization size and composition.
While we will eventually need to migrate existing team accounts to the new pricing model, we do not have any immediate plans to do so. At the moment, the restructured pricing will only apply to new accounts, or existing accounts that wish to change their team size. Because of the smaller size increments, pricing for organizations just over a size break (e.g. 101 members) will see effectively no change, with the biggest increases happening for organizations using almost all of their available size (e.g. 99 members). If you’re a paid agency that has signed up for a team account in the past few months, you’re likely already on the new model and won’t see a change.
I’m excited about our renewed focus on team functionality, and looking forward to the next few years being as impactful as the last.
Matt Jacobs
Founder, CalTopo
https://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.png00Meghanhttps://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.pngMeghan2022-08-04 12:38:412022-08-04 12:39:07A Look at What’s Next for CalTopo Teams
CalTopo Teams allows organizations to connect all their members in a single platform, promoting the seamless sharing of information. As CalTopo team accounts have been increasingly adopted by a wide variety of organizations (including search and rescue, wildland fire, SWAT teams, public land management groups, and guiding companies), we have seen a greater need for the ability to customize the platform for different use cases.
We’ve been working hard to improve team accounts and we are excited to announce the latest team account updates!
Sub-teams and Mutual Aid Incidents as seen on the team account admin page
First, there is a new feature available to all team accounts: Sub-Teams! Sub-teams allow you to organize your team membership into distinct groups that make sense for your organization. For example, a sheriff’s office may want to create specialty sub-teams (such as a canine sub-team, evidence sub-team, etc) to more accurately reflect their organizational structure. Individual members can be assigned to a single sub-team or multiple sub-teams, depending on their role in the organization.
You can also set visibility between sub-teams and the main team account. This allows you to control the flow of information, providing or restricting access to team or sub-team data as needed. For example, a sheriff’s office may want to provide a canine sub-team with upward visibility into the main team account, so that they can view maps for incidents that they are asked to respond to. However for an evidence sub-team, they may want to prevent any member who is not part of the sub-team from viewing evidence sub-team maps or data in order to protect any potentially sensitive information.
Check out the Sub-Teams page in our user guide to learn more about creating and managing sub-teams on your team account.
Second, Events are now called Mutual Aid Incidents and are no longer a separate tab on the team admin page. Sub-teams and mutual aid incidents (formerly called events) are essentially the same thing except mutual aid incidents (1) are temporary groups for responding to a large complex incident, (2) have an expiration date, and (3) can include people from outside your organization. For example, a search and rescue team that is coordinating a multi operational period search may create a mutual aid incident to rapidly onboard mutual aid from outside their team.
Finally, you may notice that there is another new feature on the team account admin page called Collaboration. At a high level, Collaboration allows teams and organizations that frequently work together to create a shared workspace for sharing maps and data. For example, a fire department that often works with a sheriff’s office could create a shared workspace that they give the sheriff’s office access to. While the feature is live on the site (and you are welcome to play around with it), we aren’t quite ready to officially roll it out yet- we’ll save that for another blog post soon!
Not familiar with CalTopo Teams and want to learn more about how a team account could help your organization? Visit the CalTopo Teams page or email us at help@caltopo.com for more information.
As high resolution elevation data becomes increasingly available through the USGS 3D Elevation Program (3DEP), we regularly make updates to our elevation dataset so that it reflects the best data out there. We recently added high resolution elevation data for some new areas that we are pretty excited to show off. No matter how many times we’ve done it, we can’t help but admire the new data.
But don’t take our word for it- check it out for yourself!
First up, take a look at the Wind River Range in Wyoming, which was one of the lucky areas that received an update. Below are two images from the Cirque of Towers, both with the MapBuilder Topo and slope angle shading layers. The original lower resolution elevation data is on the left and the new high resolution elevation data is on the right. Notice the increased level of detail in the image on the right. It is much easier to discern subtle changes in the elevation of the terrain, which might affect your route or trip planning decisions.
Above: Split image of the Cirque of Towers, Wind River Range, WY. Move the slider to compare the original lower resolution elevation data (left) with the new high resolution elevation data (right).
This difference is even more pronounced when you check out the shaded relief layer in the same area.
Above: Cirque of Towers again but this time with shaded relief. Compare the original lower resolution elevation data (left) to the high resolution elevation data (right).
Glaciated terrain might be one of the best places to gawk at the increased detail of the high resolution data. Check out Gannett Peak, also in the Wind River Range. The difference in the original and new elevation data on this glaciated peak is astounding- notice how you can spot the location of crevasses when the data was collected in the image on the right, whereas they are largely absent from the image on the left.
Above: High resolution elevation data means more details. Check out the crevasses that are visible in the high resolution image (right) but absent in the lower resolution image (left).
The Wind River Range wasn’t the only place that got an update- Yosemite National Park in California was also a winner this time around! Take a look at Slide Mountain. This one is a particularly neat example because you can see evidence of a rockslide to the east of the peak in the high resolution image on the right but it is missing from the image on the left.
Above: Even rock slides can be captured by the high resolution elevation data (right), as shown in these images from Slide Mountain, CA.
Where available, high resolution elevation data is incorporated into any CalTopo tool or layer that uses our elevation dataset. This includes layers such as MapBuilder Topo, MapBuilder Hybrid, shaded relief, slope angle shading, sun exposure overlay and custom DEM layers, as well as tools like elevation profiles. Just look at the higher level of detail the sun exposure overlay shows with high resolution elevation data in the Elk Mountains in Colorado- that update looks good on you, Elks!
Above: Blinded by the light and the increased level of detail in the sun exposure overlay with high resolution elevation data (right) in the Elk Mountains, CO.
The difference is pretty wild, isn’t it? In addition to the Wind River Range, Yosemite and the Elk Mountains, other notable areas that were part of the most recent high resolution elevation data import include:
Trinity Alps, California
California Coast Ranges
Big Bend National Park, Texas
Black Canyon National Park, Colorado
Large portions of Colorado including the Sawatch Range
To see all the areas that currently have high resolution elevation data, check out this interactive coverage map.
Where coverage is available, high resolution elevation data can be accessed from the web, mobile and desktop apps. And if you have the appropriate subscription, you can download it for offline use, allowing you to bring high resolution elevation data with you into the backcountry.
Above: Couldn’t resist one more split image, this time in Black Canyon National Park, CO on the mobile app. Move the slider to compare the original lower resolution elevation data (left) with the new high resolution elevation data (right).
At this time, CalTopo does not automatically update offline downloads when we do a new elevation data update. If you notice discrepancies between the online elevation data and your offline downloads, make sure to delete your old downloaded tiles and re-download the latest ones. More information on managing your offline downloads can be found in the Mobile App- Offline Useor CalTopo Desktop- Download and Syncsections of our user guide.
And as a reminder: while high resolution elevation data is incredibly useful for backcountry travel, it should still not be relied on as a definitive source of truth. There are limitations, including possible errors or accuracy issues with the dataset or our processing of it which can artificially create or omit terrain features. It is also important to note that all elevation data is just a snapshot of the terrain at one point in time; natural and manmade forces can dramatically alter the terrain since that data was gathered.
Always carefully assess and evaluate any terrain that you are traveling in, and confirm your observations instead of relying solely on maps. Seek professional instruction on how to travel safely in the backcountry- our partners at the American Mountain Guide Association and American Avalanche Association have some great resources to get you started.
https://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.png00Meghanhttps://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.pngMeghan2022-05-27 08:01:192022-05-31 10:42:41Latest High Resolution Elevation Data Updates
New ADS-B based aircraft tracking overlay, and hundreds of additional weather stations and statistics are now live in CalTopo alongside some cleanup of the layer list. More details about both these overlays can be found below. Access to some overlays will change slightly as part of this improvement as highlighted below.
Above: Aircraft layer over California displaying “All” Aircraft
Aircraft Layer (ADS-B)
We’ve added a real time aircraft data layer which is based upon ADS-B data from aircraft. This feature is available to all pro, desktop, and team users. Inherent to ADS-B are a couple of limitations to be aware of. There must be a receiver that can “see” the aircraft and report their locations, and the aircraft must have an ADS-B transceiver turned on. At times low flying aircraft particularly in remote valleys, or after landing will not be visible on the map. These are expected limitations, however overall ADS-B coverage is good and no filtering or blocking of military, firefighting, or medical air assets is done by the data provider.
Organizations can leverage this feature to track air assets responding to their incidents such as helicopters or fixed wing assets. If a tail number is known it makes finding and displaying that resource quite easy, but we’ve also included a number of filters. In the near future organizations will be able to add specific tail numbers and create a permanent track on search maps as needed.
Enthusiasts can also track air assets with the additional context of CalTopo topographic layers, and overlays. The example shown on the right displays aerial operations at the Dixie fire in California, several air tankers and helicopters are visible. Clicking on an aircraft displays altitude, airspeed, and additional information as available about the aircraft.The show track option allows for a short tail to be displayed in order to provide insight into where the aircraft has been as well as its direction of travel and relative speed.
All visible aircraft are displayed including high flying commercial aircraft, though our focus was on optimizing visibility of rescue and firefighting aircraft with a mapping context. This layer continues to be a work in progress and we welcome questions or feedback. We will continue to make incremental improvements and tweaks over the next weeks.
Above right: Colors based upon temperature. Above left: Colors based upon wind speed
Realtime Weather
Fortunately or unfortunately our real time weather station layer became inoperable a number of months ago due to changes at our former data provider. We have since moved to a much more robust data source that contains a significantly larger number of weather stations throughout the US and includes data in Canada. Many stations also report additional variables as compared to our previous data source such as relative humidity and air quality. This expanded coverage and high quality data, comes with significant cost increases for CalTopo. As a result, this layer will only be available to Pro, Desktop and Team users beginning in October. Until that time the realtime weather will remain available to free and mobile users. Note that this includes the former SNOTEL and water gauge overlays (which are now enhanced with additional data as well).
Each station is now colored based on a selected variable such as temperature, or air quality allowing at a glance assessment of current conditions across a wide region. The former individual water gauge and SNOTEL real time data overlays are now integrated
into this layer as part of the drop down selections with additional data sources, these overlays are now enhanced with additional snowfall measurement sensors and flow meters.
Clicking on an individual station reveals more information about data collected by that specific station including some basic information, temp, wind speed, etc. There is also a link for a customizable and interactive 7 day data graph from that location.
Many of these stations report tons of additional information (such as altimeter, max or min 24-hour temperatures, etc). These fields are currently displayed (seen above), however are not “prettified” at this time and may not have a unit associated with the measurement. Over the next months we intend to refine and clean up the display of these additional data points honing in on the most valuable additional data available.
Weather Shading Overlay and Weather Grid Data
We’ve combined the former weather grid overlay with the weather shading overlay. Numeric temperature values are now displayed on the weather shading layer at the center of the 2.5km grids, zooming in is required. Subtle differences in color can be challenging to interpret so these numeric readouts help give more precision. NOAA spot forecasts are still available via right click “NOAA Forecast” (seen in above screenshot). This is available even when this overlay is not displayed. The closest available spot forecast will load in a new tab without requiring searching for an individual forecast grid dot to click on.
“Your” Data Overlay
This layer now displays all map objects from your maps and any team maps from team(s) that you are a member of. You can use the “your tracks” filter to display only tracks from saved maps. Tracks are actually traveled and recorded via GPS, either in the CalTopo app or imported via a file that has preserved time/gps data.
Shared CalTopo Maps Overlay
This layer has gotten some filtering improvements as well including displaying only tracks (ensuring that the route has actually been travelled) as well as sorting only popular shared maps that other users have bookmarked and found useful. Additional future improvements are planned to ensure shared maps are easier to find and sort through.
Shared Locations
For members of a single team there is no change to this layer. If you are a member of multiple teams you now can select between teams using a drop down instead of an individual shared location layer for each team. The shared location layer now includes the option to display a short tail for each user being tracked in order to infer rate and direction of travel. In order to record a complete track users still need to record track from their device, though additional improvements to this functionality are forthcoming.
https://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.png00Ben Lantowhttps://blog.caltopo.com/wp-content/uploads/2019/10/caltopoLogo_menu1.pngBen Lantow2021-07-26 08:11:242021-07-26 08:13:34Real Time Updates: Aircraft and Weather
CalTopo is looking to fill two remote developer positions:
A UI / UX developer. We are are looking for someone with a mix of design and web development skills, who can assist with design across the entire platform (mobile + web), and also put that design into practice on the web stack.
A full stack developer. Our specific tools are mostly Java and Javascript (currently plain JS + JQuery but migrating towards TypeScript and React), but a good well-rounded development background is more important to us for this role than experience in specific languages or tools.
A good candidate for either of these positions, will be able to independently take on a multi-week development project with minimal supervision. Usually, this means a bachelor’s degree in computer science plus several years of pertinent work experience.
While this is a remote-work position, one of the two hires needs to reside in California – we need 50% of our employees to be CA residents in order to quality for health insurance. Beyond that, we have a slight preference for CO or WA residency as we are already setup to operate in those states. Either way, occasional (post-pandemic) travel to Truckee, CA will be required.
CalTopo offers a flexible work environment, health insurance, generous PTO, and of course, the ability to improve a product that you use on a regular basis.
CalTopo has always made its map layers available to other apps and websites, but we’ve decided it’s time to phase that out. Our slope angle shading layer will no longer be available outside of CalTopo on Oct 1, with all other layers no longer available in other apps and sites in January 2021. We know that this will inconvenience some of our customers who also use other apps, so we wanted to take a minute to explain our decision.
What does that mean for users come October 1 or January 2021? If you’re used to using the CalTopo slope angle shading, topographic maps, or other layers outside of the CalTopo website and app, you will no longer be able to do so as of these dates. The only way to access CalTopo layers and maps will be in the CalTopo app and on the CalTopo website.
There are three major reasons we’re doing this:
* Improve our ability to develop new layers. As we look to expand internationally, we will increasingly be incorporating proprietary datasets that we need to license. There is no way we can seamlessly incorporate proprietary data into our existing tilesets, while continuing to license those tilesets to other users. Maintaining a stable API also hinders our ability to make technical improvements such as switching to 512 pixel tiles.
* Cost control. While layer licensing generates some revenue, maintaining a public endpoint is also costly – CalTopo spends thousands of dollars a month on bandwidth alone. We recently discovered that a much larger company was driving those costs up by using our tileset without permission, and had to go multiple rounds with an attorney to get them to stop. It will be easier for us to implement technical measures to block unauthorized use if we do not also need to support licensed use.
* Control of our brand. Only a portion of CalTopo’s layer set is available for licensing, and over time many of the pre-rendered, licensed layers have diverged from what is available on CalTopo. For example, the slope angle shading on CalTopo has greatly improved in both coverage and accuracy compared to the version that we license out, and because we render it on the fly, there’s no scalable way to give other apps access. This has been an ongoing source of confusion, and it’s been difficult to explain clearly how XYZ app “has some CalTopo layers, but not all, and the ones they do have don’t fully match ours”.
In order to make for a smooth transition, we’ve given apps that license our layers significant advanced notice, so that they have time to find or create alternate tilesets. CalTopo has always had a generous free use policy, and we intend to continue allowing free noncommercial use of our tilesets going forward – with the caveat that such use is a secondary consideration, so there may be short-notice changes that free users will need to adapt to.
Note: This post was updated on 9/11/20 to include information about the GOES Live Fire Layer as well as the GOES Live Satellite Imagery. We also attempted to address some of the most frequent questions we’ve gotten over the last few weeks in our help forums.
With the increase in wildfires across the Western US in the last week we’ve seen a huge spike in usage on CalTopo as well as numerous questions. This post contains a LOT of information about imaging, data sources, and methods, some of which was previously covered in some older blog posts in 2017 and 2018 but is updated here.
First and foremost: If you’re in an area near a wildfire follow your local authorities for evacuation notices and up-to-the-minute information. If you are in a life-threatening situation CALL 911. While maps provide valuable insights into fire behavior and areas affected, a map is always just a representation of the best available data. Sometimes data is delayed or erroneous. Above all things, please stay safe and healthy.
Data Sources
CalTopo aggregates data from a large number of sources that provide insights for fire fighters, fire managers, and the general public. These features have been added over the years, unfortunately usually as a result of fire activity. One of the informative and currently relevant is the Fire Activity overlay.
The MODIS program consists of two satellites Aqua and Terra, that pass around the Earth covering the entire Earth once every 24hrs. As of 8/16/20 the Aqua satellite is not producing fire data consistently (reference here). MODIS satellites have a resolution of 1km, which means that they can differentiate down to a 1km square but within that km x km box the satellite cannot further differentiate where heat/smoke are. MODIS data is available as a standalone imagery layer (Daily or Nightly Low-Res in the base layer drop down).
VIIRS
The VIIRS program is a newer program and provides a higher resolution than MODIS (375m instead of 1km, more than two times better). VIIRS similarly provides multiple passes around the Earth every 24hrs with two different satellites and is a major part of the current fire activity layer. As with MODIS, VIIRS images from the NPP satellite are available as raw images. However unlike MODIS, in the fire activity layer both VIIRS Satellites (NPP and JPS-1) are labeled VIIRS on the map.
NIFC
When selected the current fire activity layer displays satellite data in conjunction with data from the National Interagency Fire Center on the map. NIFC maintains data from incident managers including specific incident mapping obtained using GPS tracks from group crews and information from firefighting aircraft.
NOAA Hazard Mapping
NOAA Hazard Mapping provides 3 levels of smoke polygons, from low to high smoke (lightest grey to black in the images). The data is displayed only when “with smoke” is selected. The polygons can be very large and overlap with a lot of other data. This provides some insight into smoke, although it doesn’t tell us how bad the air quality or smoke is in that path. We’re continuing to look at adding air quality information and other smoke forecast information in the future.
Note that a satellite has to pick up the hot spot, the image needs to be processed and then the data has to be pushed out publicly for a fire to appear on our maps. With the recent lightning fires in California and with the incredibly dry conditions, fires started quickly and spread very rapidly. We saw delays of 12+ hours after starting before fires would appear in mapping. Fires can start very rapidly and grow incredibly quickly and VIIRS and MODIS programs only pass over the Earth 1-2 times each day.
Using the Fire Activity Overlay
There is a drop down menu for the Current Fire Activity overlay that allows selection from All Satellites, with smoke, MODIS, VIIRS 375m, VIIRS Progression, and IR Progression. Each option provides a slightly different dataset or view. As you zoom in on maps additional information is revealed.
All Satellites, MODIS, VIIRS 375m
The infrared data from both MODIS and VIIRS contribute to hotspot detection, from which we can infer fire activity. As seen above (this image is from the 2020 LNU Lightning Complex Fire) the time and date of each hot spot along with the satellite that the data came from is always available. If you select just MODIS or VIIRS 375m from the dropdown menu you’re also able to see temperature and power (measured in megawatts) of that data point. This is shown below.
Each hot spot also has an error radius around the point based upon error reporting from the satellites. The location of the satellite in relation to the Earth, as well as the resolution of the instruments on the satellites feeds these error rings. The best view of the Earth from a satellite is from directly above, toward the edge of images the view becomes more oblique and can result in more error (MODIS satellites are especially prone to this), this would be represented by larger circles around hot spots. A good option may be to switch satellites to get a better vantage point. Additionally we see some “false positives” along or ahead of the edge of the fire, while the reasons for this are not exactly clear, it likely has to do with the satellites sensing heat from smoke and gases coming off the fire. Finally each hot spot is color coded based on time of the report. Red are most recent (less than 12 hours), then orange (12-24 hours), and finally yellow (24-48 hours). After 48 hours we remove the hot spot from the map.
Additionally we display the active fire perimeter from the National Interagency Fire Center (formerly GeoMAC) on all the satellite views. These perimeters are updated 1-2 times daily typically and come directly from incident management teams. They are based on a combination of reports from fire crews, satellite information and fire aircraft doing infrared flights or firefighting. If the fire has been named that name is also displayed on the perimeter polygon. This is shown below with the perimeters for the Loyalton Fire in Northern California (below left). When zoomed further out these perimeters become a small flame icon instead (Northern California/Nevada in August 2020 is shown below right)
With Smoke
The “with smoke” option adds the NOAA Hazard Mapping System smoke data. The smoke is designated with gray to black crosshatched polygons, the lighter the polygon the lighter the smoke (light gray is low, grey is medium, black is high). (Smoke over California and Nevada in August 2020 are shown below).
VIIRS Progression and IR Progression
The other options in the dropdown are progression layers that show a color coded progression over longer periods of time. The VIIRS progression layer shows VIIRS hotspots for more than just the 48hrs the baser layer does (a legend is under Fire Info in the top right of the page). The IR Progression layer is currently disabled due to changes in the way data was reported, we plan to update and bring it back online in the coming months.
GOES Live Fire Detection (Experimental)
GOES 16 and 17 are geostationary satellites positioned over the eastern US (16) and western US (17), streaming images back to Earth on a near-real-time basis (within 10 minutes, as compared to the above discussed VIIRS and MODIS satellites). The imagery from these satellites is frequently used for animated loops of hurricanes and other large-scale weather events. In addition to raw multi-spectral imagery, NOAA also releases a number of derived datasets, one of which is active fire detections. In the daytime, these fire detections are reported at 5 minute intervals.
CalTopo has incorporated the active fire detection information on our maps, seen right. The layer is found right below the Fire Activity Layer checkbox and is called “GOES Live Fire Detection”. The colors of pixels correspond to the time of the fire detection, the legend is available the top right corner and there is no information about temperature available in this layer, Active Fire Overlay provides that information.
This layer is updated live (new information within 10minutes at the longest). In addition to the satellite’s rapid update interval, the CalTopo map layer will auto-refresh to ensure you are always looking at the most current information, and the time of the last satellite image is displayed on the layer. For new or rapidly moving fires, this can be useful information to supplement between MODIS and VIIRS satellites passes from the “fire activity” layer.
However, each pixel is roughly 2km by 2km, so this layer will only show larger fire activity. An error of a single pixel is enough to place a fire over a mile off from its true location – this is not a layer that will give you insight down to the level of whether a specific neighborhood has burned. The “fire activity” layer is better for that use case, although even that is still an imprecise tool that only reports approximate locations and is easy to over-interpret as having more precision than it does.
Using Other Overlays for Fire Information
There are a number of other live data overlays available in CalTopo that can help inform fire behaviors. Both live temperature and wind layers can be useful and are found listed under Weather Forecast. Both are based on live NOAA data. The wind plot shows current wind direction (indicated by arrows) and speed (indicated by color with a legend on the page in the top right corner). There are dropdown menus to select speed versus gust speed and for time (from now all the way out to 36 hour forecast speeds). We also maintain a fire history layer with about 20 years of fire history also from the National Interagency Fire Center (image far right). While this isn’t much “history” it’s the best source of data we’ve found to date. Perimeters are colored by age, with name and year the fire occurred listed as you zoom in (here, red again is most recent)
CalTopo has also incorporated the. realtime imagery from GOES 16 and 17 which can be found as a base layer called GOES Live (seen right). The realtime imagery is kept up to date and automatically refreshes just like the Realtime fire layer. Images will be delayed no more than 10minutes from time of acquisition and typically smoke is visible from this layer, as are other large scale meteorological events (such as hurricanes, storms, etc).
Because the GOES satellites are geostationary and far from the Earth resolution of this layer is limited (around 1000m resolution), you won’t be able to see your house or van from the images. The Global Satellite Imagery layer, NAIP Aerial Imagery, or the Google Maps Satellite layers all provide much higher resolution (as high as 0.5m in places, though mostly between 1-5m resolution) , however they are only updated every few years, not in minutes. The Sentinel Weekly imagery is a happy medium providing a high resolution layer updated every 5 days that displays approximately 10m resolution images that can be used for things like snowpack detection as well as some evaluation after fires. Sentinal imagery requires a Pro subscription to use.
Other Data Sources
There are a variety of other data sources to inform decision making about fires. Local sheriffs’ offices, fire departments, and emergency management agencies provide a huge amount of information about fires nearby, and are proactive with pre-evacuation notices and evacuation notices. Additionally inciweb is a huge source of information with contact numbers, resources, fire size, containment, and evacuations. NIFC provides more general wildfire information and has links back to inciweb for further details about specific fires.
As our app has evolved we are moving away from the our mass beta test and into a more stable update cycle!
What does this mean to our users? More regular, stable, incremental releases with features and bug fixes as well as a much more polished app than 1 year ago. It also means that we are looking for a pool of dedicated beta testers interested in testing stable pre-production releases.
Beta versions may contain new features, often without documentation yet. These true beta version will have been vetted by our internal team, but may contain small bugs still specific to the ways you use the app. We’re looking for tech and map saavy users on both iOS and Android who are willing to give us feedback on their experiences (good and bad!).
If you’d like to continue to beta test the application the following is a link to sign up for our beta tester pool: https://forms.gle/wNycnQmUrovTCy1a6
If you don’t want to continue to beta test, just update the app as usual from the Google or Apple store and you’ll be all set!
As many SAR teams are using online and remote trainings to maintain physical distancing, CalTopo is offering a free, 2-hour SARTopo webinar training. This training is designed to help search and rescue personnel get started using SARtopo to create effective maps for planning and executing missions.
Specifically the training will cover the following items:
1. Familiarization with available base layers, overlays, and objects.
2. Drawing and managing assignments.
3. Sharing maps, collaborating with other personnel, and printing maps.
4. Managing track data.
… and a bonus section on data organization.
We are offering this training several times over the next couple of weeks, on 5/28/20 and 6/3/20 at 5pm Pacific and 6/2 and 6/8 at 6pm Pacific all online via Zoom.
Space is limited and pre-registration will be required.