Sunday, April 10, 2016

4/10/16: Extreme Weather in the U.S.

This week we are exploring extreme weather events. In the figure from weatherunderground on the right you can see how today in the States there are a few happening, like high wind advisory, severe thunderstorm warning, and fire weather advisory.

Knowing your weather patterns matters. As the climate changes, so will the weather. As an example, January 2016 was the most abnormally warm month ever recorded (NASA, NOAA sources). This winter, areas across the globe experienced a shift in rain patterns due to the natural weather phenomenon known as El NiƱo. A new NASA visualization of rainfall data shows the various changes in the United States with wetter, wintery conditions in parts of California and across the East Coast.

The visualization below shows the rain accumulation from December 31, 2015 to January 6, 2016 with red patches indicating heavy amounts of rain accumulation over California. During this time an extreme event hit the state causing landslides. Credits: NASA/Goddard/Hal Pierce.


Global patterns like more droughts, more heavy downpours, heat waves, etc. can be linked to extreme weather events (NOAA). NOAA staff says: “The point here is that these events are causing up to billions of dollars of damage. As we see the increasing trends in these metrological and hydrological extremes, as a society we really need to think about how we are going to manage the risk, how we’re going to adapt to these changes in extremes.”

NOAA’s National Climatic Data Center provides a variety of information detailing all these extreme weather events. Their yearly maps of U.S. Billion-dollar weather and climate disasters are very informative. We are to alone, the world map of significant climate anomalies in 2015 (figure) is clear.



Interesting times…


Sunday, April 3, 2016

Free Workshop: GIS & Mobile Technology (April 26)


Join Us For A Discussion Of GIS And Mobile Technology!

Sponsored by MPC Foundation & AMBAG


CCJDC announces a free workshop event April 26th from 9am-3pm at the Marina Library in Marina, CA. Due to exceptional interest and the exciting technologies being presented, the time for the event has been extended until 3pm.
The workshop will cover applications of GIS for mobile devices. We look forward to having you join the conversation and see demos of mobile technologies utilized locally. Presentations will be followed by a participant-led discussion session, networking opportunities, and a light lunch.
Hope to see you there!
Ana
http://www.ccjdc.org/events/2016/4/26/mobilegisworkshop
AGENDA
8:50
Welcome
9:00-9:30
Talk 1 : Geocortex
9:30-10:00
Talk 2 : Soquel Creek Water District - Field Mapplet Implementation
10:00-10:30
Talk 3 : Santa Cruz County Public Works - Lucity Implementation
10:30-10:45
Break
10:45-11:15
Talk 4 : Anatum Field Solutions - Centimeter Bluetooth GNSS for your Tablet or Smartphone
11:15-11:45
Talk 5 : T4 Demonstration
11:45-12:45
Lunch Break
12:45-13:15
Talk 6 : CSDS - Intro to Trimble R1 & R2 GNSS Receivers and RTX Real Time Correction Service
13:15-13:45
Talk 7 : Scheid Vineyards - Viticultural Technologies: Mobile & Web GIS in Action
13:45-15:30
Solutions Experts Anatum Field Solutions, CSDS, Geocortex, Group Mobile, Lucity, Spatial Wave
15:30
Farewell – See you at GIS Day, Nov. 16th, 2016!
Special Thanks to:


Sunday, March 20, 2016

3/20/16: LANDSLIDES IN CA

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 1982, a series of landslides near San Francisco killed 33 people and closed the Golden Gate Bridge. A total of 18,000 different landslides took place in the San Francisco Bay Area following a very heavy rain storm (data collected by aerial surveillance in the days following the event). Two fast-moving fronts carrying extremely heavy rain passed through in a 36-hour period, during which the area received an amount of rain equal to half its average annual precipitation. 

Another famous unstable area is La Conchita. A mudslide of 400,000 tons of mud in 2005 killed 10 people. This should not be surprising as the exact same place suffered another hill collapse in 1995, destroying 9 homes. In that occasion, the landslide consisted of 600,000 tons of mud and silt slid 600 feet down a cliff face (see topo map in the figure. Note all houses are built donwlope of a very steep slope...).

The obvious approach is study well the soil in where we put homes and also learn from previous occurrences, understanding that areas that are unstable will continue being so  (La Conchita is not alone; Oso area had been unstable before the 2014 event).  Detailed geologic reports have been made in the past of these places, but the personnel that has the power to act have not followed up/ignored them or have not read them. Gravity always wins. We know better?

After the 2005 disaster, there was an attempt of a $50-million grading project. There were also calls for the county to buy up all the homes through eminent domain and never allow anyone to live there again. It was an idea that came and went, as was the grading project.

There is a USGS page with information on how to identify landslides and what to do if one happens: http://landslides.usgs.gov/learn/prepare.php


Sunday, February 28, 2016

2/29/16: Minimizing Volcanic Hazards: 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. 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 the following U.S. volcanoes as to be above normal background (elevated unrest or eruptions) or have shown activity that warranted an Information Release (for example, an earthquake swarm):

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


Kilauea Alert Level=WATCH. Aviation Color Code=Orange
Note: this one has been erupting for 33 years! (see more here).


More information @


All for now-

Sunday, February 14, 2016

2/14/16: Only For Quake Lovers: Exploring Seismicity and Mitigation Strategies

If I want to know something about earthquakes, the first websites I go to are: the USGS Real Time Earthquakes Website or the IRIS monitoring website.


This week we are exploring seismicity and what countries do to prevent/mitigate the hazard.

Re: the first issue, the new 2014 US map of seismicity (see image 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 Madrid Zone 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).

A great new blog post summarizes nicely the Cascadia subduction Zone dangers....

Re: the second issue, I want to focus on a brand new effort by the USGS: the 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 might make all the difference (enough to stop transit/elevators and to drop, cover, hold on). All for now-


Sunday, February 7, 2016

2/7/16: Introduction to Geological Activity at Plate Tectonic Boundaries

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

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!

Of course, there are a few exceptions, like the 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!

Other interesting Plate Maps can be found at USGS or Esri: interactive. All for now-


Sunday, November 15, 2015

11/16/15: COASTAL HAZARDS IN THE US


The National Assessment of Coastal Change Hazards of the USGS has very good information about coastal issues in the country.

Also, 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.

All for now-