Wednesday, July 7, 2021

Increased Threats from Glacial Retreat

Climate changed has influenced various processes and the composition of various biomes around the world. One of the most affected areas are glaciers, with mountain glaciers all around the world experiencing immense amounts of retreat. Apart from losing hundreds of miles of glacial cover, the tragedy continues through the increased occurrence of flash flooding due to the glacial waters increasing river flow below and breaking through rock an d debris that once acted as a dam.

Thousands of individuals have been lost to these floods in various parts of the world including the Himalayas and Andes. Efforts to mitigate these threats are being looked into by the Swiss, Canadian, and Indian governments. Most recently, there were possibilities of similar catastrophes occurring Alaska.

The use of remote sensing could help to predict where certain areas are of risk. This may also inform governments of the appropriate preventative measures that could be taken to either evacuate communities or push forward construction projects to deter water from flooding specific areas.   

The image above displays how glaciers had melted in the Himalayan Mountains, consequently adding to the water volume of the Rishiganga River and flooding the village of Raini. This image was created by Planet Labs. 

Original Article: https://www.nytimes.com/2021/02/08/climate/climate-change-flash-flood-india.html

Warehouse Explosion in Beirut: Before and After

 


These images show the state of a seaside warehouse in Beirut, Lebanon before and after a    massive explosion. The explosion was caused when a crate of ammonium nitrate caught fire. As the image shows a massive crater is left along with heavy damage to buildings around it. These satellite images complete devastation to the port and the buildings around it, along with a ship that was blown out of the water and onto the dockside. These images are important for disaster diagnosis and prevention along with emphasizing the importance of locating dangerous materials in a populated place.

  https://www.wionews.com/world/beirut-explosion-created-massive-crater-at-port-satellite-                    imagery-shows-318495
















See How China Built Two COVID Hospitals Within Days

These satellite images are provided by the China Land Observing Satellite Data Center. These images are the locations of two new COVID hospitals built in Wuhan, Hubei Province earlier in 2020. To counter the pandemic in Wuhan, the Chinese government decided to build two completely new infectious disease hospitals borrowing the experience from Xiaotangshan Hospital built during the SARS outbreak in 2003. The decision to build the first hospital, Huoshenshan Hospital was made on January 23. The construction began on January 25, and was completed on February 2. Shortly after the start of the construction of Huoshenshan Hospital, the second hospital, Leishenshan Hospital also began construction. Leishenshan Hospital was completed on February 6. The two hospitals had over 2,000 beds in total, they played a critical role in China's fight with the COVID-19 pandemic. These satellite images showed the huge effort China made and the Chinese people's confidence against COVID.

Construction of Huoshenshan Hospital (30.5291°N 114.0822°E)
Caidian District, Wuhan, Hubei Province

Construction of Leishenshan Hospital (30.4320°N 114.2883°E)
Jiangxia District, Wuhan, Hubei Province


Source (in Chinese): https://www.thepaper.cn/newsDetail_forward_5842152

Viewing the Changing City Environment through remote sensing


The images in this series work to highlight the change in building and urban land cover. The images show how over the past 40 years we have seen a massive increase in land cover, in areas where the urban environment already existed. Not only are we expanding into new areas, ones already considered part of the Washington D.C. metro are being expanded upon. This image includes an overlay that allows the viewing of more information beyond the base image. It also makes the information more easily accessible to the audience. They dont need to be trained in remote sensing and viewing information from overhead imagery to know what is happening in these photos.

https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/04/13/satellite-maps-shows-explosion-in-paved-surfaces-in-d-c-region-since-1984/

 

Using Citizen Science and Remote Sensing to Detect Toxic Algae

 These images are from a study done at The University of Georgia to try to detect and treat toxic algae blooms sooner than was previously possible. The images show algae blooms in two different lakes in Florida and Nevada (Figure 1 and Figure 2). These images, along with on-site sensors show the presence of an algae bloom. The research team developed an algorithm to search social media sites where people may be posting about blooms that they cannot detect from the satellite imagery. Using information gathered from this algorithm, the team can look at satellite images of the water body to determine if there is a bloom. They then will alert local authorities to allow them to test the water to determine the toxicity of the bloom. Along with the algorithm, they also have an app that allows citizens to put in data all over the world. The research team hopes that between citizens providing local data, and their ability to detect blooms through satellite imagery, they will be able to sooner detect and treat toxic blooms across the world.



California's Drought is Worse Than We Realize

These satellite images show the stark contrast of the Angeles National Forest and the San Gabriel Reservoir outside the Los Angeles metro area from 2020 to 2021 and highlight the severity of the drought that the western United States faces.  The top image shows the southern California landscape in June of 2020 in relatively lush vegetation cover and reservoir level contrasted with the image from this June below. In 2021 we see a dry, red landscape with little vegetation and a significantly reduced water level in the San Gabriel Reservoir.


California has experienced a severe drought for nearly a decade with little reprieve and just had its driest February in 150 years, leading to reduced snowpack and runoff that much of the state relies on for its drinking water.The dry conditions also escalate the probability of wildfire – something California and the western US have become all too familiar with in the last decade. Last year was the worst fire season in the state's history but with severely reduced rainfall and snowmelt and soaring heatwaves, it could easily surpass the record the state set in 2020. 

The images were captured by the European Space Agency's Sentinel satellite.


Angeles National Forest and San Gabriel Reservoir, June 2020


Angeles National Forest and San Gabriel Reservoir, June 2020



Link to original article: https://www.theverge.com/2021/6/22/22545107/satellite-images-california-drought-water-esa

Less tree cover in formerly redlined areas of Philadelphia compared to rich neighborhoods

 

These images are part of an interactive essay from the New York Times that examines the amount of tree cover present in affluent neighborhoods of Philadelphia (e.g. Chestnut Hill, Fig. 1) and compares that to tree cover in formerly redlined districts of the city (Fig. 2). The authors (Ian Leahy and Yaryna Serkez) use data from maps to present fascinating visualizations of the amount of tree canopy cover in rich vs. poor neighborhoods, which can cause large differences in average temperatures (they report up to 10 degrees Fahrenheit) and affect the general wellbeing of residents. The interactive essay assists in visualizing the problem using effects such as highlighting key areas with polygons and labels. It's clear from the imagery used how many more trees exist in Chestnut Hill compared to the formerly redlined areas, indicating the continuing effects of discriminatory housing practices from decades ago.  


Fig. 1: a wealthy neighborhood called Chestnut Hill (highlighted and outlined in white borders) shows high levels of green tree canopy, which contributes to resident's wellbeing. 


Fig. 2: formerly redlined areas of Philadelphia are shown bordered and shaded with red. There exists a clear lack of green tree canopy in these regions.


Image and story source: https://www.nytimes.com/interactive/2021/06/30/opinion/environmental-inequity-trees-critical-infrastructure.html

Ancient Earthworks Discovered in Kazakhstan with Google Earth


 


Hoping to learn more about the ancient history of his country, a business manager named Dmitriy Dey began studying satellite imagery of Kazakhstan via Google Earth to find clues of structures created by his ancestors. What started as a hobby quickly turned into a large project that has inspired archeologists all over the world to study the sites he found by examining imagery and has lead to numerous theories on their origins as research has not caught up to say how old these earthworks are let alone which peoples used them or for what. 


The image above and the project generally is controversial because Dey has discovered 260 features that he claims are upwards to 8,000 years old and part of a Neolithic sun cult, but experts warn the images can be misinterpreted without investigation on the ground. Geidre Motuzaite Matuzeviciute, an archeologist from the Lithuanian Institute of History in Vilnius, believes that only 55 of these features are ancient earthworks with the remaining created later by Turkish tribes. While these 55 still require ground teams to investigate, it's still very exciting that the patterns that identified these could only be seen with remote sensing and these particular features were only discovered because a 'layperson' had access to free data to research his personal interests. Whether or not these images are historically significant will be verified by later research and peer review. 


Source: These Satellite Views of Ancient Earthworks Are Stirring Debate (nationalgeographic.com)




Almeda wildfire impact— in the US and arround the world.

 

Like every year, the West Coast wildfires are massive and devastating. Due to climate change, dry weather conditions between California and Oregon have been the reason of tons of fuel available to start this massive fire.  In 2020, Oregon and California wildfires have exceeded a record turning thousands of acres of forest area into ash, making it the worst wildfire in the past 18 years. In Figure 1, you can see the damage caused by Almeda fire made in Mountain View Estates, Oregon, which it forced thousands of residents to evacuate from their homes, and where approximately 30 people died during the wildfire. In addition, high levels of smoke were able spread through several East Coast states in the US, even crossing the Atlantic Ocean reaching some Europe skies getting repercussions on climate change. Moreover, NASA captured images tracking large clouds of smoke and associated aerosols caused by the fire on its way through the states of New York and Washington DC (Figure 2).


Fig 1. Mountain View Estates neighborhoods surface destroyed by Almeda fire at Talent, Oregon.



Fig 2. Wildfire smoke spread from the west to the east of the US.



Source: https://www.bbc.com/news/world-us-canada-54180049

Mapping of Mangrove Forest on the North-Western Coast of Guyana

 

Mapping of Mangrove Forest on the North-Western Coast of Guyana


The map above displays the location of mangrove forests along the north-western coast of Guyana by using satellite imagery to detect the above-ground biomass. This is a product of training sessions with SERVIR Global and relevant NGO and government agencies to improve the monitoring of mangrove forests. This is an important initiative because mangrove forest provides critical ecological services to Guyana. However, there is very little data on the status of the vegetation which is being threatened by climate change and anthropogenic activities. This collaborative initiative is part of a bigger plan to protect and preserve the ecosystem.

 Source: https://servirglobal.net/Global/Articles/Article/2728/ensuring-resilience-for-people-and-ecosystems-guyana-advances-mangrove-monitoring-with-satellite-technology



Tracking Deforestation in Peruvian Amazon



Both of the images above show us the change in landscape and vegetation in the area of central Peruvian Amazon. The first picture was taken on March, 2020, meanwhile, the second picture was taken on November, 2020 by Planet/MAAP for ABC News.

The pictures above give us an idea of the severity of the deforestation activity that is taking place in the Amazon rainforest. The image on the left allows us to see quite an undisturbed area of natural vegetation. The image on the right gives us a look into how serious the forest has thinned due to human exploitation. The brown-red color that shows up more regularly in the later picture also proves that forest clearing is leaving the land bare and exposed. Activities such as mining and agriculture was provided to be some of the main contributors to the area's rapid deforestation.

To read more about Amazon deforestation, visit: 

https://abcnews.go.com/International/amazon-rainforest-lost-area-size-israel-2020/story?id=75683477



Cameron Peak Fire

Remote sensing in the media has become ubiquitous, with satellite imagery appearing in everything from the news to sitcoms to blockbuster movies, and even commercials. Given the varying levels of quality and interpretability, there is much to think about and discuss!


Wednesday, July 7, 2021


The Cameron Peak Fire burned from August - December 2020.  To this day it is  Colorado's greatest wildlife, burning over 200,000 acres in approximately 5 months time.  Although the cause of the fire still remains unknown, its origins are still under investigation.  In total, Larimer County (where Fort Collins is located) tallied over 450 structures damaged or destroyed.  To add, approximately 30,000 acres or almost 9% of Rocky Mountain National Park were burned.  

Fig. 1

Evacuations (mandatory and voluntary) west of Fort Collins, CO

Image without a caption 

Fig.1 Displays the evacuation outcomes for residents in mid-October 2020.  This is image is important as it could have been used by residents to gain a better understanding of how they're being influenced by the fire.  To add, this map, along with others supplied by Larimer County were updated regularly.  This map can also be important for authorities attempting to inform future citizens about what can happen; as in all likelihood there will be more fires in the future.  

Fig. 2

Smoke Plume of Cameron Peak Fire

Image

Fig. 2 Displays the smoke plume of the Cameron Peak fire on October 14, 2020.  This map portrays the extent of the smoke and is important to residents of the area, as they can monitor to an extent how impactful the smog outside their homes will be.  To add, having this smoke information public is a valuable resource, as officials and the public will be able to compare its results to that of future or past events.  


Tuesday, July 6, 2021

Impacts of Severe Drought on California Reservoirs: 2020 - 2021

California has been experiencing below average rain fall between 2020 and 2021. As of July 6th, 2021, approximately 85% of California is extreme drought per the U.S. Drought Monitor Index. 

Below are images of Lake Oroville captured by the Copernicus Satellite and obtained through MAXAR Technologies. The top-most image displays Lake Oroville in 2020. At this point in time,  the lake is relatively full and vegetation is lush green. However, in 2021, the reservoir has decreased significantly. There is far less water in this lake and you can now see the sandy soil that is now exposed on the edge of the reservoir. Additionally, the vegetation that was green this time last year is now very dry and bare, indicating high levels of stress.

To access the original webpage and use the interactive slider, click here:

https://www.cnn.com/2021/06/18/weather/california-drought-satellite-images-wx-trnd/index.html

Lake Oroville 2020

Lake Oroville 2021






 




Landslide: Chamoli, Uttarakhand, India,

 


    The above satellite image of the Himalayan mountains was taken at the origin and path of a landslide that devastated Chamoli, India on Feb. 7, 2021. The origin of the landslide is located in the bottom right portion of the image, while its path (represented by the yellow-dotted line) meanders from the bottom right to top left portion of the image. The destructiveness of this event was exacerbated by heavy water flow due to natural causes (e.g., glacial melt and heavy rains) as well as the presence of hydroelectric plants (e.g., Tapovan Hydroelectric Plant--located in the upper left portion of the image).
    It was initially thought that the landslide was caused by the collapse of a glacier, resulting in a glacier outburst flood. However, scientists led by Dr. Dan Shugar used seismic measurements to determine when the landslide began and subsequently were able to locate satellite images of the location mere hours after the landslide occurred, including one taken 10 minutes after the beginning of the landslide and another 27 minutes later. Using these images, in conjunction with eyewitness reports and video as well as other remote sensing data, Shugar and colleagues determined that the actual cause of the landslide was a massive rockfall (one of the largest ever recorded) at Ronti Peak. The devastation of the rockfall was exacerbated by large amounts of glacial meltwater, recent heavy rainfall, and water released from hydroelectric dams in the path of the landslide, which increased the speed and mobility of the landslide as it moved down the mountain. Unfortunately, those in the path of this landslide had little warning, but Shugar and colleagues found evidence of instability at Ronti Peak dating back to at least 2016, suggesting that remote sensing can allow for the establishment of early warning systems in the Himalayas and other landslide-prone areas.

Relevant Links:
https://www.planet.com/pulse/rapid-response-research-the-chamoli-landslide/
https://science.sciencemag.org/content/early/2021/06/09/science.abh4455



Study using satellite data had shown sinking land in Florida a year before the recent condo collapse

 



Shimon Wdowinski, a professor in the Department of Earth and Environment at Florida International University, analyzed datasets from the Interferometric Synthetic Aperture Radar (InSAR) to located where coastal flooding may cause the ground to sink. Results from the April 2020 study showed that the land where the Champlain Towers South condo was built in 1981, has been sinking at a rate of 1.9 mm per year (top circle on image) because it was built on reclaimed wetlands. Wdowinski said that this sinking rate alone would not cause the condo to collapse and pointed out that there are other areas that have a higher sinking rate per year (bottom circle). InSAR technology is also used to detect cracks in buildings which are an indicator that the building has moved in some way. That movement can go hand in hand with the sinking of the land beneath it, but in most cases there is not a tragic event that follows. 

https://www.dailymail.co.uk/news/article-9723841/Map-report-predicting-condo-collapse-reveals-Miami-Beach-spots-risk-collapse.html