Sunday, November 10, 2019

Week 13: COASTAL HAZARDS IN THE US


When I think about coastal erosion, I think about Pacifica, CA, and the 2016 after el NiƱo related storms, when yet another chunk of sandy cliff was falling into the ocean and houses were in need of abandonment. A drone video of the area is clear. A lot of information can be found about how in a few years the cliff has eroded.

Recently two online portals have been developed as an interactive tool for any user to explore what coastal hazards are all about. Also, the National Assessment of Coastal Change Hazards of the USGS has very good information about coastal issues in the country.

The NOAA’s Sea Level Rise Viewer website let you browse over possible scenarios of sea level rise and coast vulnerability. A great link to try!

Today I am going to focus on another link, the USGS Coastal Change Portal. The USGS Coastal Change Hazards Portal is a new tool that allows anyone to explore how coasts change due to: extreme storms, shoreline change, and sea level rise.

Extreme Storms: this allows ‘real-time and scenario-based predictions of storm-induced coastal change, as well as the supporting data, are provided to support management of coastal infrastructure, resources, and safety.’ For example, let’s focus on the Gulf Coast and a scenario of a hurricane (any category). Let’s see how a Cat 1 and a Cat 5 possibly looks like (with probabilities of collision (dune erosion), overwash, and inundation for sandy beaches along the Gulf and Atlantic coasts during a generalized hurricane landfall): see figures for both. The most probable areas should be risks areas and treated as such in an emergency.

Shoreline Change: this shows: ‘historical shoreline positions and rates of change along ocean shorelines of the United States’. Looking into the East coast now, offshore Norfolk, see figures for long-term coastal change rates, and for the short-term rates (<30 years rates of shoreline change for open-ocean shorelines of the United States ranging from 1970's to 2001).

Sea level Rise: there are two methods used to address this: a Coastal Vulnerability Index (CVI), and a probabilistic assessment of shoreline change. 
CVI: ‘a preliminary overview, at a National scale, of the relative susceptibility of the Nation's coast to sea-level rise through the use of CVI. This classification is based upon the following variables: geomorphology, regional coastal slope, tide range, wave height, relative sea-level rise and shoreline erosion and accretion rates. The combination of these variables and the association of these variables to each other furnish a broad overview of regions where physical changes are likely to occur due to sea-level rise’. A quick image shown here shows how much red (very high vulnerability) our California coasts possess.




Probabilities of Shoreline Change: ‘this dataset was used to develop and evaluate the performance of a Bayesian network (BN) that predicts long-term shoreline change associated with sea-level rise. The BN is used to define relationships between driving forces, geologic constraints, and coastal response, which includes observations of local rates of relative sea-level rise, wave height, tide range, geomorphology, coastal slope, and rate of shoreline change. Using this information, the BN is used to make probabilistic predictions of shoreline change in response to different future sea-level rise scenarios’. See same area of CA and look at the area of south San Francisco.

As you can see this new tool will help tremendously to manage areas and to get a broad idea of what is happening on the US coasts.

Explore these links!-

Saturday, October 19, 2019

Week 10-Extreme Weather in the US


As we currently watch post tropical cyclone Nestor approach Florida [see image below from NHC], a round of severe thunderstorms, with damaging winds, hail and isolated tornadoes, is possible Sunday and Monday from the Plains to the lower Mississippi Valley. The chance of severe weather will build due to a familiar early winter-like setup that includes the intersection of a strong low-pressure system with warmer, more humid air ahead of it from the Gulf of Mexico.


The Weather Prediction Center shows the map below for tomorrow, with further predictions of thunderstorms moving east with each passing day.

As expected, 2018 was the fourth-hottest year on record globally, and another near-record year for U.S. weather and climate disasters, see image below. 


While the U.S. had its 14th-warmest year in 2018, unusual heat in Europe and the Arctic propelled the globe to higher numbers. The oceans also had their warmest year on record — a trend that intensifies sea level risecoral bleaching, and tropical cyclones such as hurricanes.

Any of these websites are great places to keep yourselves informed so we can prepare for a heat wave or a storm coming our way.

Saturday, October 5, 2019

Week 8-Mass Wasting Events in the US


Landslides in the United States cause approximately $3.5 billion in damage, and kill between 25-50 people annually. The largest landslide in modern U.S. history (in terms of volume) was most likely one that occurred in 2013 in Bingham Canyon outside of Salt Lake City, Utah. It had a slide mass of 55 million cubic meters (compared to an estimated 10 million cubic meters during the Oso event in 2014, see image below).
Landslides impact California’s terrain often. These are generally related to precipitation patterns, in particular if there has been previous months of drought conditions. In January 2019, Pacific storms brought a lot of rainfall to the state. The heavy rain forced residents to evacuate from wildfire-ravaged areas. The “high risk” areas for mudslides are so because they are adjacent to steep slopes or are located at the base of drainage areas. Recent examples are the ‘Woolsey’ and the ‘Hill’ fire burn areas, which will be subject to high volume of mud and debris flow moving forward. The photo below shows a 2019 example.


Oso mudslide image

If you want to know more about these hazards, the USGS page has great information on how to identify landslides and what to do if one happens. If you want to know if you are living in a risk area, you can access maps like the USGS below that shows the Emergency Assessment of Post-Fire Debris-Flow Hazards.

image of the 2019 aftermath of landslides in south CA

Stay informed and safe-



Saturday, September 14, 2019

Week 5- How to minimize Volcanic Hazards in the US: USGS Alert Codes


This week Geol9 is exploring the volcanic hazards in different countries and their warning systems. I’ll be focusing on the US.

There are several ways we minimize the danger of volcanic activity (apart from the obvious of ‘getting out of the way’…(J:

·         Forecasting (earthquakes as early warnings -although in 2014 a Japanese volcano erupted without any previous seismicity (livescience article), land swelling before eruption, gas emissions, etc.)

·         Volcanic Alert Codes (USGS): the levels of alert and the aviation code levels commonly change at the same time (chart on right). A non-erupting volcano will have a green icon, and a red one indicates an imminent eruption (see USGS Alert Codes).

Today the US hazards map shows 4 volcanoes as to be above normal background (elevated unrest):

Cleveland and Mauna Loa Alert Level=ADVISORY. Aviation Color Code=Yellow.

Semisopochnoi and Shishaldin  Alert Level=WATCH. Aviation Color Code=Orange.



Saturday, August 24, 2019

Tectonics explains a LOT of natural hazards


This week 2 we are exploring plate tectonics and how important it is to know the location of the plate boundaries, and how it is closely related to some natural hazards, like volcanoes or earthquakes.


In the US, the NOAA map below shows how the Easter part of the States is a passive margin, and the Western side of the country is a very active one, with the Pacific Plate, Cocos, Juan de Fuca plates connecting to the North American plate. Not a surprise we are on the ‘Ring of Fire’, where a lot of the volcanic and seismic activity happens!


Of course, there are a few exceptions, like the activity of Hawaii within the Pacific plate (hot spot) or the New Madrid area (ancient rift) within the North American Plate, both not at plate boundaries, but that will be another post another time...

We might not know when events like volcanic eruptions or big earthquakes will happen [note that a lot of these happen underwater...], but if you know your Tectonics, you definitely know where the do!

Thursday, August 15, 2019

WELCOME TO FALL 2019, LOBOS!

Hello Geol9,

Welcome to class. 


We start the semester in peak months of the Hurricane Atlantic Season. NOAA forecasters monitoring oceanic and atmospheric patterns say conditions are now more favorable for above-normal hurricane activity since El Nino has now ended.


Stay tuned...


Sunday, April 28, 2019

COASTAL HAZARDS IN THE US


When I think about coastal erosion, I think about Pacifica, CA, and the 2016 after el NiƱo related storms, when yet another chunk of sandy cliff was falling into the ocean and houses were in need of abandonment. A drone video of the area is clear. A lot of information can be found about how in a few years the cliff has eroded.

Recently two online portals have been developed as an interactive tool for any user to explore what coastal hazards are all about. Also, the National Assessment of Coastal Change Hazards of the USGS has very good information about coastal issues in the country.

The NOAA’s Sea Level Rise Viewer website let you browse over possible scenarios of sea level rise and coast vulnerability. A great link to try!


Today I am going to focus on another link, the USGS Coastal Change Portal. The USGS Coastal Change Hazards Portal is a new tool that allows anyone to explore how coasts change due to: extreme storms, shoreline change, and sea level rise.

Extreme Storms: this allows ‘real-time and scenario-based predictions of storm-induced coastal change, as well as the supporting data, are provided to support management of coastal infrastructure, resources, and safety.’ For example, let’s focus on the Gulf Coast and a scenario of a hurricane (any category). Let’s see how a Cat 1 and a Cat 5 possibly looks like (with probabilities of collision (dune erosion), overwash, and inundation for sandy beaches along the Gulf and Atlantic coasts during a generalized hurricane landfall): see figures for both. The most probable areas should be risks areas and treated as such in an emergency.


Shoreline Change: this shows: ‘historical shoreline positions and rates of change along ocean shorelines of the United States’. Looking into the East coast now, offshore Norfolk, see figures for long-term coastal change rates, and for the short-term rates (<30 years rates of shoreline change for open-ocean shorelines of the United States ranging from 1970's to 2001).

Sea level Rise: there are two methods used to address this: a Coastal Vulnerability Index (CVI), and a probabilistic assessment of shoreline change. 
CVI: ‘a preliminary overview, at a National scale, of the relative susceptibility of the Nation's coast to sea-level rise through the use of CVI. This classification is based upon the following variables: geomorphology, regional coastal slope, tide range, wave height, relative sea-level rise and shoreline erosion and accretion rates. The combination of these variables and the association of these variables to each other furnish a broad overview of regions where physical changes are likely to occur due to sea-level rise’. A quick image shown here shows how much red (very high vulnerability) our California coasts possess.

Probabilities of Shoreline Change: ‘this dataset was used to develop and evaluate the performance of a Bayesian network (BN) that predicts long-term shoreline change associated with sea-level rise. The BN is used to define relationships between driving forces, geologic constraints, and coastal response, which includes observations of local rates of relative sea-level rise, wave height, tide range, geomorphology, coastal slope, and rate of shoreline change. Using this information, the BN is used to make probabilistic predictions of shoreline change in response to different future sea-level rise scenarios’. 
As you can see this new tool will help tremendously to manage areas and to get a broad idea of what is happening on the US coasts.

Explore those links!-

Thursday, March 21, 2019

Mass Wasting Events in California


Landslides in the United States cause approximately $3.5 billion in damage, and kill between 25-50 people annually. 
The largest landslide in modern U.S. history (in terms of volume) was most likely one that occurred in 2013 in Bingham Canyon outside of Salt Lake City, Utah. It had a slide mass of 55 million cubic meters (compared to an estimated 10 million cubic meters during the Oso event in 2014, see image below).

Landslides impact California’s terrain often. These are generally related to precipitation patterns, in particular if there has been previous months of drought conditions. In January 2019, Pacific storms brought a lot of rainfall to the state. The heavy rain forced residents to evacuate from wildfire-ravaged areas. The “high risk” areas for mudslides are so because they are adjacent to steep slopes or are located at the base of drainage areas. Recent examples are the ‘Woolsey’ and the ‘Hill’ fire burn areas, which will be subject to high volume of mud and debris flow moving forward. The photo below shows a recent example.



If you want to know more about these hazards, the USGS page has great information on how to identify landslides and what to do if one happens. If you want to know if you are living in a risk area, you can access maps like the USGS below that shows the Emergency Assessment of Post-Fire Debris-Flow Hazards.

Stay informed and safe-


Saturday, February 23, 2019

Volcanoes Week


Our Geol9 class is exploring the volcanic hazards in different countries and their warning systems. I’ll be focusing on the US.

There are several ways we minimize the danger of volcanic activity (apart from the obvious of ‘getting out of the way’…(J:

·         Forecasting (earthquakes as early warnings -although in 2014 a Japanese volcano erupted without any previous seismicity (livescience article), land swelling before eruption, gas emissions, etc.)

·         Volcanic Alert Codes (USGS): the levels of alert and the aviation code levels commonly change at the same time (chart on right). A non-erupting volcano will have a green icon, and a red one indicates an imminent eruption (see USGS Alert Codes).

Today the US hazards map [below] shows 4 volcanoes as to be above normal background (elevated unrest):

Veniaminof, Kilauea, and Great Sitkin Alert Level=ADVISORY. Aviation Color Code=Yellow.

and Cleveland Alert Level=WATCH. Aviation Color Code=Orange.


If you want to know more about volcanoes and how we monitor them, there is a MOOC from the University of Iceland that starts in March you might want to enroll into. A short video explanation here

Sunday, February 10, 2019

EARTHQUAKES IN THE STATES


This week we are exploring earthquakes and what countries do to prevent/mitigate the hazard. If I want to know something about earthquakes in a place, the first websites I go to are: the USGS Real Time Earthquakes Website or the IRIS monitoring website.

Re: where quakes are located in the US, the 2014 US map of seismicity (see image below from USGS) shows the (obvious, in pink) ring of fire portion on the West coast but also a central area in the middle of the plate. I’d like to talk a bit more about this non-obvious one. This area, called the New MadridZone was shaken by a M8(!) in 1811. The reason for the activity is a very old intraplate rift placed below the area (see image from http://showme.net).


The San Andreas Fault System is responsible for most of California natural quakes...we had over 550 in the last month...up north, the Cascadia Subduction Zone will be responsible for next big one that area has. So, at least we start to knwo the 'why' of these quakes.

Re: the 'what to do about it', apart from the obvious need for education, I want to focus on the USGS ShakeAlert system, developed for the West coast using some of the existing systems. Today, the technology exists to detect earthquakes, so quickly, that an alert can reach some areas before strong shaking arrives. The purpose of an EEW (Earthquake Early Warning) system is to identify and characterize an earthquake a few seconds after it begins, calculate the likely intensity of ground shaking that will result, and deliver warnings to people and infrastructure in harm’s way. Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds, depending on the distance to the epicenter of the earthquake. 


A few seconds of warning could make all the difference (enough to stop transit/elevators and to drop, cover, hold on).



Being aware of the risk and know what to do when the shaking starts is very important. We know that earthquakes cannot be predicted [I recommend Dr. Jones’ book called the big ones if you want more information about that]

All for now-


Monday, February 4, 2019

Week 2 in Geol9- tectonic plate boundaries as responsible for geological activity


This week we are exploring plate tectonics and how the location of each country is affected by its position respect to plate boundaries.
map of tectonic plates

The NOAA map shows clearly how the Easter US is a passive margin and the Western side of the country is a very active one, with the Pacific Plate, Cocos, Juan de Fuca plates connecting to the North American plate. Not a surprise we are on the ‘Ring of Fire’, where a lot of the volcanic and seismic activity happens! Just recently in my twitter feed this story below was developing....a detected seismic swarm [multiple small quakes] in progress in southern Cascadia.
swarm quakes in Cascadia from temblor twitter feed


Of course, there are a few exceptions, like the current activity of Hawaii (hot spot) or the New Madrid area (ancient rift), both not at plate boundaries, but is for some other time.

We might not know when events like volcanic eruptions or big earthquakes will happen, but if you know your Tectonics, you definitely know where the do happen!

All for now-
Other Plate Maps found at USGS or Esri: interactive

Saturday, January 26, 2019

Welcome-Intro; world-wide natural catastrophes in 2017


Welcome to my Geol9 online blog!

This Spring semester, our course will cover the application of basic principles of Earth processes, including tectonics, erosion, climate, as well as issues of catastrophic and disastrous events from a global perspective. We’ll explore and learn about earthquakes, landslides, floods, severe weather, tsunamis, volcanoes, etc. The course also emphasizes using the scientific method to interpret the causes and future probabilities of Earth catastrophes and disasters.

Our two SLOs are
·  Explain the cause of Earth catastrophes and disasters.
·  Estimate the geologic hazards of various locations on the Earth.

According to Munich Re, overall losses from world-wide natural catastrophes in 2017 totaled $330 billion dollars, up from $184 billion in 2016. That says a lot. I hope you find this course useful. Ranked by insured losses, the costliest natural catastrophe in 2017 was Hurricane Irma that caused $32 billion in insured losses in the United States and the Caribbean. Hurricane Harvey in the United States resulted in $30 billion in insured losses. Rounding out the top 5 catastrophes by insured losses were Hurricane Maria in the Caribbean with $30 billion in losses; wildfires in the United States in October that resulted in losses of $8.0 billion; and hailstorms in May that caused $2.5 billion in losses [see world map below].