Monday, 31 December 2007

Orientation...then Oceano to Santa Barbara

Having just 'beamed' back into the blog, I have spent a little time this morning reacquainting myself with the basics of the geography of California and so I thought I might produce a simple map for reference....

Mark began his Californian journey at San Fransisco where the waters of the two rivers which drain the Central Valley (Sacramento from the north and San Joaquin from the south) flow out into the Pacific Ocean. Much of his journey so far has taken him through the Coast Ranges and along the Pacific coast between San Fransisco and Los Angeles. Although the web diary reports several steep climbs in the Coast Ranges, they rise only to an average of 1000m compared to the 3000m+ peaks in the Sierra Nevada.
Climatically, California enjoys a Mediterranean climate - not unlike the climates of Perth and Adelaide in Australia with their hot, dry summers and warm/mild and wet winters. This climate graph for Sacramento ( east of SF in the central Valley) is probably average for the state but there are huge variations across the state caused by altitude and relief. In the south, the rainshadow effect of the coast ranges, and with prevailing NE winds combine to create desert conditions while in the Sierra Nevada altitude lowers temperatures sufficiently to give 'sub arctic' conditions in winter with heavy snowfall.

After the rains of New Zealand, it looks as if it could potentially be the same in California - January is the wettest month!
Relief and climate have much to do with the distribution of population in California as the map (left) shows. Lowest densities correspond with the highest and driest areas.

Orientation over...... this is the route which Mark followed yesterday from Oceano to Santa Barbara. It suggests that he reached Santa Barabara around 5pm local time (01.00 on the 31st GMT). As you can see from the map, there was a significant change of direction... more of which later.

The first part of his journey yesterday took him across the apparently dry Santa Maria river at Guadalupe and into the intensively farmed plains around Santa Maria
At the time the Google Map image was taken, the river would have been dry for two reasons a) seasonal summer drought and b) its headwaters are dammed as part of a water management and conservation scheme . Only in winter is there sufficient rainfall for the channel to carry water. Clearly, therefore, the river does not bring significant irrigation potential to the Santa Maria area. Agriculture must be based on crops which can grow in the wetter winter or survive the summer drought. In the latter category are vines which are widespread in the region.

There are also several large areas of greenhouses such as these - similar to the greenhouses now found in many parts of southern Spain where the enclosed environment helps to control moisture loss. Elsewhere, small reservoirs holding water stored from the winter, dot the farming landscape..

South of Santa Maria, in the hills between Santa Maria and Lompoc, Mark will have cycled close to the Vandenberg Air Force Base which, as you can discover if you follow the link, has played an interesting strategic, defence and space reserach role over the years.

As readers of this blog will know, I have had several opportunities along the route of Mark's journey to explore 'large white blobs' in the Google Earth imagery. Today there is another one! This time it's at Lompoc (apparently pronounced 'lamb poke'). It took a bit of research but I finally got an answer - these white blobs are the Miguelito Mine where diatomaceous earth is mined. Never heard of the stuff? Neither had I until I read this.

South of Lompoc both the coastline and the trend of the coastal ranges change direction. These are the Transverse Ranges which according to Wikipedia " lie between Santa Barbara and San Diego counties. They derive the name Transverse Ranges due to their East-West orientation, as opposed to the general North-South orientation of most of California's coastal mountains. Their orientation along an east-west axis as opposed to the general southeast-northwest trend of most California ranges results from a pronounced bend in the San Andreas Fault". So now we know! Mark crossed a part of the Transverse Ranges - the western end of the Santa Ynez Mountains -after joining Highway 101 and heading south to the coast at Gaviota. A narrow pass, seen below on Google Earth ,carries the route through a tunnel...And here, the rest area at the southern end of the pass....

The coastal stretch between Gaviota and Santa Barbara is scantily populated - indeed, several sources note it as one of the last remnants of undeveloped coastline in California. One feature, however, caught my eye when viewed from the air..... not a mine as it seemed at first but a huge landfill zone which copes with most of the 'trash' generated by Santa Barbara county.

Which brings us finally to Santa Barbara !
..with a guided tour of the city by young Jay

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