Santa Monica Bay - Now At Higher Risk of a "Stealth Tsunami" - 2012

 

Santa Monica Bay - Now At Higher Risk of a "Stealth Tsunami"

In the 1950’s, prior to the California surfing craze, riding an inflatable raft in Pacific Ocean surf was more fun than anything else I could imagine. However, growing up in Burbank, California at that time implied a landlocked existence. Luckily, our own natural water park, at Sorrento Beach in Santa Monica was only an hour away by car. Several times each week of summer vacation, my mother drove us to the shore of that crescent shaped bay.

In later years, polluted runoff entering Santa Monica Bay contributed to rising cancer rates among L.A. County Lifeguards. The statistics were enough to deter swimming at Southern California beaches. Even though my visits to the shore were rare, I often dreamed about Santa Monica Bay. In those dreams, I stood ashore as an unseen tsunami approached from the west. After the Indian Ocean Tsunami in December 2004, I wondered about the tsunami threat in Santa Monica Bay. When the March 2011 tsunami hit the east coast of Japan, some of the heaviest damage occurred in and near Sendai.

Sendai, Japan stands at the head of a crescent shaped bay similar to Santa Monica Bay. While reviewing maps and pictures, I could see a tsunamical signature in the creation of Matsushima Bay, just north of Sendai. That “bay within a bay” is an archipelago of small, but towering islands, most having little or no beach. Lost in prehistory, a cataclysmic tsunami struck the coast at Matsushima. That huge series of waves quickly inundated and eroded the land, sweeping most of it out to sea. Today, those small, towering islands are all that remains of headlands that once overlooked the Pacific Ocean.

Earth scientists have long known that crescent shaped bays amplify wave action by focusing it at the head of such landforms. Within the city limits of Crescent City, California, Crescent Bay is one of half a dozen crescent shaped inlets. From the Great Alaskan Earthquake of 1964 to the Japanese Earthquake and Tsunami of 2011, Crescent City often takes the brunt of Northern California tsunami activity. According to researchers at nearby Humboldt State University, the city experienced tsunami conditions more than thirty times between 1933 and 2011.

With the help of satellite mapping and paleo-flood surveys, there is sufficient data to prove that crescent shaped bays do more than amplify tsunami. It is my thesis that tsunami help to create crescent shaped bays, both large and small. As sea levels rise annually at a rate between 1.7 mm and 3.3 mm, the threat of destructive tsunami also rises. Each cubic foot of water weighs over sixty-two pounds. Even a small rise in sea level places staggering extra inertia behind waves concentrated by a crescent bay. In Japanese, tsunami means, “harbor wave”.

Reflecting on my dreams of Santa Monica Bay tsunami, I now pay closer attention to crescent shaped bays that I visit. Three of my favorite Pacific Ocean bays are Natewa Bay, Catalina Harbor and Hanalei Bay. Each of the three bays is unique and beautiful. Their common heritage includes both tsunamical creation and vulnerability to future tsunami.

In 2001, I visited Natewa Bay, Vanua Levu, Fiji. Immediately, I was struck by its size. Throughout the South Pacific, it is second in size only to Subic Bay in the Philippines. Our buree at Lomalagi Resort overlooked the head of Natewa Bay. Each day, we watched as the tides emptied and then refilled the bay. Stripped down to old coral and bedrock, the long, narrowing bay magnifies any tidal action. If not actually created by tsunami, Natewa Bay appears to have hosted many such events. Around 2005, some development wags proposed building human made islands in the upper reaches of Natewa Bay. Although the development website still exists, we see no sign of actual development. With high tsunami risk at Natewa Bay, near shore development makes no sense.

The small town of Two Harbors is located at Isthmus Cove, Santa Catalina Island, California. Facing the Southern California coast, Isthmus Cove is a reliable anchorage for pleasure craft. On the far side of the isthmus is Catalina Harbor. Similar to Natewa Bay, “Cat Harbor”, features a south facing underwater canyon. The isthmus, a gently tapered mound of earth, rises only sixty-two at its high point. If a thirty-foot tsunami arrived from the south, the isthmus at Two Harbors could easily become a “tsunami sweep”. It is easy to visualize a tsunami-induced flood topping the low isthmus and spilling into Isthmus Cove, on the far side.

Hanalei Bay, on Kauai, Hawaii is a classic tsunamical bay. Lying at the foot of the Hanalei River Valley, there is no deep canyon beneath the bay. The mouth of the almost circular bay opens to the northwest. Rather than sediment from the river extending into the Pacific Ocean as a delta, exposure to tsunami and other extreme wave action has carved out a semicircular bay. Within the gentle sloping river valley, great tracts of farmland remain vulnerable to future tsunami.

In my recurring tsunami dream about Santa Monica Bay, I stand onshore. As I look out to sea, the ocean water recedes. Then, with no warning, I see a large tsunami racing toward me. I turn, as if to run from the approaching wave. As the towering tsunami overwhelms me, I find that it is made of cloudy foam. At the time of my inundation, the great wave evaporates and whisks away like a fog. In my dreams, the Great Tsunami of Santa Monica Bay causes no harm. In our real world of rising seas and continued earthquake activity, we may not be so lucky.

Email James McGillis

 

By James McGillis at 05:52 PM | Environment | Comments (0) | Link

Oregon - One Step Forward and One Step Back... 2008

Oregon - One Step Forward and One Step Back...

In July of any year, one of the nicest places to visit is the southern coast of Oregon.  U.S. Highway 101 is the primary access route, north and south.  Additionally, several highways cut east and west, winding along the river valleys and upper canyons, providing a change of scenery from the coastal strip.

 

Driving north from California across the Oregon border brings a couple of shocking revelations.  When you arrive in Brookings, which is the first town you will encounter, you will notice that motor gas prices are about twenty cents cheaper per gallon than in California.  The lack of a retail sales tax and lower state fuel taxes makes Oregon a great place to fill your tank.

 

 

Well, maybe not so great, once you realize that Oregon does not allow self-service filling of one’s own fuel tank.  The supposed “positive result” of this archaic law is that it keeps thousands of Oregonians employed as gas station attendants.  The downside is that during the summer tourist season, motorists queue up at the lower-priced stations, engines idling and pollution spewing from their tailpipes as they wait. 

 

Despite the many “Keep Oregon Green” signs that one sees along the highway, old energy and old-style thinking are adding an immense load of greenhouse gases to the Oregon air shed.  If estimates are true that the average vehicle produces about one pound of carbon dioxide for each mile driven, how many additional tons of carbon dioxide do Oregon motorists produce in order to make dead-end jobs for some of their residents?  Additionally, how many hours of lost productivity do Oregonians suffer as frustrated motorists wait in line for fuel that they could safely pump without assistance?

 

Once you get past the pros and cons of Oregon’s fuel pricing and dispensing methods, you can breathe a sigh of relief as you motor north towards Gold Beach, some twenty-five miles beyond the California border.  If you have breakfast or lunch in Gold Beach, you will notice that the pace of life is a bit slower than California.  If you allow yourself to slow down and match the natural pace in Southern Oregon, you will enjoy your experience far more than if you simply rush towards your destination.

 

In the early days of travel along the Oregon Coast, towns sprang up along the highway approximately every twenty-five miles.  The ostensible reason for this spacing related to how far a horse-drawn vehicle could travel in one day.  With that idea in mind, twenty-five miles north of Gold Beach is the sleepy town of Port Orford, famous in its heyday for the “Port Orford Cedar” trees that covered its coastal slopes.

 

Although hidden from the highway in many places, the coastal strip between Gold Beach and Port Orford has several direct openings to the sand and surf.  Owing to the gentle slope of the continental shelf in this area, low tides pull far out from the beach and high tides rush in on large breaking waves.  Flotsam from Asia and driftwood from the Pacific Coast are among the prizes awaiting the intrepid beachcomber.

 

Although the commercial port at Port Orford is so small that they haul out the fishing fleet with dockside cranes, it is the only deep-water port along the coast between Portland, Oregon and the San Francisco Bay.  Protected by headlands to the north and west, the small port remains vulnerable to storms approaching from the southwest.

 

As with several other Southern Oregon coastal towns, much of Port Orford lies within the “tsunami zone”.  Once erroneously called “tidal waves”, Americans have adopted the Japanese word “tsunami”, which means, “One or a series of huge sea waves caused by earthquakes or other large-scale disturbances of the ocean floor”. 

 

Nearby Crescent City and Eureka, California has each experienced tsunamis in the past fifty years.  Many places along the Oregon coast show geological evidence of large-scale tsunami activity, although contemporary coastal dwellers tend to downplay or ignore the potential threat.  At Port Orford, one has to travel nearly a mile inland to find ground high enough for the state to declare it a “tsunami safety zone”.

 

Whether it is for reasons of tsunami safety or lack of sewage plant capacity, Port Orford qualifies as the only town along the highway where recent commercial development is almost unknown.  Although there is a new library adjacent to the highway, there are no chain restaurants in town.  The pharmacy closed its doors a few years ago, leaving only a clinic to tend to the healthcare needs of the many retired residents.  The infrastructure is so antiquated and poorly documented that the local water system was recently losing between one third and one-half of its stored water to leaks in the system.  Many leaks are nearly impossible to track down and fix in the wetlands and other marshy areas around the town.

 

Founded in 1851, Port Orford is the oldest town along the coast.  Its population of less than 1500 is not much different than it was in the late 1800s.  In its heyday, Port Orford featured a sawmill that efficiently transformed the old-growth Port Orford Cedars into planking for sailing vessels and later for insect and mildew resistant cedar-shake shingles.  Both the sawmill and the old-growth cedars are gone now, leaving retirement living and tourism as the top two economic engines for the town. 

 

If you are looking to live far away from city life and can accept that the nearest major medical center is in North Bend, almost sixty miles away, Port Orford allows a pace of life and a heavily wooded landscape not often seen in contemporary America.  If you do build or buy there, you might want to check the tsunami map before doing so.  There has been no tsunami lately, but that is no guarantee of future calm waters

 

Unlike coastal areas farther north, the Southern Oregon coast rarely experiences frost, although the area can be windy and rainy in the fall, winter and spring.  During the summer months, the weather can be clear and beautiful.  It can also be overcast and gloomy, but rarely is the area hot, when judged by standards of the inland Western U.S.

 

Viewing the area from the air for the first time can be quite a shock.  What looks like untouched forests, when viewed from ground level, looks like a logger’s paradise from the air.  Often loggers leave only a fringe of untouched forest along the highway.  Forest products are an essential industry in Oregon, but every time I see a load of scraggly and twisted old-growth tree trunks barreling down the highway towards the chip mill, I cringe.

 

With its many coastal state parks, Oregon makes amends for its questionable logging practices.  To its credit, forward thinking Oregonians, such as the 1960s Governor Tom McCall helped pass legislation setting aside most of Oregon’s 363-mile coastline as parkland or open space.  No other coastal state can boast such forward thinking in its use of irreplaceable coastal environments.  Additionally, there are many public campgrounds and private RV parks tucked into the shady groves along Highway 101.

 

If you have an RV and have the time, a trip north or south along Oregon’s Highway 101 is well worth your time.  Just don’t let your engine idle while you wait in line for fuel.

Email James McGillis

By James McGillis at 07:58 PM | Environment | Comments (0) | Link