That's the chance you take living in our Great Valley in Central California. The Tule Fogs are a way of life, and this is their time of year. If you want to be guaranteed an atmospheric/astronomical show it just can't be. But still I had to try. I took some pictures of the "Supermoon" yesterday evening in the hopes that I would see the eclipse in the early hours of the morning. Either the fog would be there or it wouldn't.
I got semi-lucky. There most certainly was fog, but it was mostly thick on the ground and the moon was still visible above. These shots may not be quite as sharp as they would be on a clear night, but they work.
There are three oddities happening at once, although two of them can be said to be kind of arbitrary...
First, there's the Blue Moon. That's one of the arbitrary ones. The lunar cycle is 29.53 days, but some of our months have 30 or 31 days, so there can be two full moons in a month. This is the second full moon of January, hence the "blue moon". The term originally had to do with 13 lunar cycles in a full year, with one season having an extra full moon.
Then there is the "supermoon". This is sort of arbitrary, being not an astronomical term, but more a modern astrological term. It refers to the full moon happening when the moon is closest to earth, therefore producing a slightly larger disk (14% greater than a "micromoon") with the additional light (30% more) that reflects from the Moon's surface. Astronomers would prefer to call this the perigee syzygy.
It is the lunar eclipse that is the best part of the evening's festivities. The Moon is passing through the Earth's shadow, causing it to darken considerably and seem to glow red as a result of light refracting through the Earth's atmosphere (the "Blood Moon"). I haven't seen an article that mentions this, but I imagine if we were on the Moon right now there would be a red ring around the edges of the Earth's sphere.
There hasn't been a combination of a "supermoon", a Blue Moon, and a lunar eclipse since 1866, so I guess it is special that way, but I find any lunar eclipse to be special. There is speculation that the slightly closer approach of the Moon has an influence on the occurrence of great earthquakes and the like, but the difference in the gravitational attraction is negligible, and statistical analysis doesn't bear this out. I guess we'll see what happens around the world today, but remember that dozens of earthquakes happen every single day, so a magnitude 5 or 6 quake somewhere is not that remarkable.
In any case, I lucked out with the fog and was able to capture the beginning of the lunar eclipse, but there won't be any shots of its end because the fog has thickened. Thus I am up at 5:00 AM blogging, which is most certainly not my usual habit! I guess there is a certain symmetry that I just finished with a month long reminiscence of ten years of geoblogging with an article on the solar eclipse of last August, and I start the eleventh year of blogging with a lunar eclipse. In any case, enjoy, and if you are up and skies are clear, go take a look!
Wednesday, January 31, 2018
Sunday, January 28, 2018
A Singular Moment...Okay, Three of Them: A Total Eclipse, Ten Years of Geotripping, and the 2,000th Post
At last, the exploration through ten years of geoblogging is complete! I've been going through the archives looking for my favorite posts and we've reached the end of 2017. I was trying to decide what post from 2017 could serve as the final one from this short mini-series, and I decided it needed to be about a singular event, one that I was not likely to experience again. But in this post, there are three. There's only one time one gets to have a tenth anniversary of anything. And there's only one time that a person reaches a numerical milestone, and this post is one of them. It's the 2,000th post on Geotripper! And the third, out of the archives, was my adventure to see the total solar eclipse that took place last August. I'll be in my eighties by the time it happens in the continental U.S. again, so I expect it was my last.
Whether we would even see the eclipse at all was a dicey proposition. We were on the coast of Oregon, and although mornings had been clear all week, the morning of the eclipse was foggy. We had a great spot on a beautiful section of coastline at Seal Rock State Park. In the end, the fog never lifted, but we had a view anyway, and one of my pictures was different enough to be featured on EarthSky.com (link at the end of the blog).
As for the whole 2000th blog and ten years thing, mostly I'm surprised that it went on this long. I had no way of knowing at the beginning that I would find enough to talk about, but frankly the Earth is a place of unending fascination, and there is always going to be something incredible going on somewhere, and there will always be a new place to see, a new adventure to experience. I don't know what lies ahead, but my intentions are to make the world knowable to as many people as possible.
There are many reasons for this, and chief among them is the age-old human desire to tell stories. But even more important in my mind is the need to defend the Earth. I could never have foreseen that we would be cursed with such a greedy and ignorant administration as the one that exists now in Washington. They deny the reality of climate change, and they have shown an eagerness to sell off and open to mining and drilling the most precious of our public lands. They are trying to dismantle the system of controls and regulations that protect our air, soil and water. This course of action is morally wrong and physically unsustainable.
Ignorance and greed can and will destroy the fabric and stability of society. I will continue to blog about our planet because I think we need more storytellers, and we need more scientists. I hope we can continue this journey together for a long time!
The post below appeared on August 21, 2017...
Yeah, I was really taking a chance, choosing to stay on the Oregon Coast for the 2017 eclipse. The reason? The fog. And there was a lot of it. To make the long story short, it never really lifted, but we could still see most of the sights through the clouds. I didn't get to see much of the corona, but there were lots of Solar prominences to compensate. It was an awesome experience in the end, but my nails are bitten down to the nubs!
We started out from Florence at 4:40 AM, not wanting to miss a parking spot. There was not a lot of traffic, and we were absolutely thrilled to see parking spaces at Seal Rock State Park. The fog was a concern, though, and the sun was still not at all visible at 8:30.
The crew at Seal Rock was stubborn though. There was some discussion of trying a different spot, but most everyone stayed, hoping for a break in the clouds. It never happened, but the clouds thinned enough that the Sun shown through. I suspect that made things a bit more dangerous, because the clouds made the eclipse glasses almost useless, and UV light could still damage people's eyes. I trusted my cameras to filter things for me (I was shooting with two Panasonic Lumix DMZ FZ70 with a 60x zoom; one on a tripod, the other handheld). I started snapping photos.
At the beginning, the Sun was the show with a couple of sunspots visible, one almost dead-center, and the other near the lower left quadrant.
More of the Sun's surface was covered, and it was becoming difficult to focus on the crescent sun in the rapidly dimming light.
Despite the warnings, I realized I could get pictures at this point without the filter, so the next couple of pictures are the true color of the Sun: white.
The discontinuities on the right edge of the crescent below are mountains on the Moon splitting up the sunlight.
The crowd at Seal Rock had been chattering away throughout most of the buildup to totality, but there was a sudden hush of shock and awe as the Sun suddenly disappeared, and it was as dark as night.
The Solar prominences glowed pink around the margins of the disk. As noted before, the corona was not visible through the fog.
There was an audible gasp in the crowd as the first streaks of light appeared on the other side of the Moon. The prominences quickly disappeared in the bright shinning light.
And then totality was over as the sky began to lighten up after 1 minute and 25 seconds of darkness. We didn't get to see the stars and planets, but I was not going to complain. What we saw was simply awe-inspiring. I understand that not everybody can drop everything and go across an entire country to see a shadow for less than two minutes, but if you ever have an opportunity, don't pass it up! It's a common experience of humanity to see the Sun blotted out by the Moon, and witnessing one in person can help one understand the myths and legends that grew around eclipses. I literally felt like shouting for the dragon to let the Sun back out of its mouth.
Update: Very pleased that EarthSky posted one of my pictures! http://earthsky.org/todays-image/photos-aug-21-2017-total-solar-eclipse
Whether we would even see the eclipse at all was a dicey proposition. We were on the coast of Oregon, and although mornings had been clear all week, the morning of the eclipse was foggy. We had a great spot on a beautiful section of coastline at Seal Rock State Park. In the end, the fog never lifted, but we had a view anyway, and one of my pictures was different enough to be featured on EarthSky.com (link at the end of the blog).
As for the whole 2000th blog and ten years thing, mostly I'm surprised that it went on this long. I had no way of knowing at the beginning that I would find enough to talk about, but frankly the Earth is a place of unending fascination, and there is always going to be something incredible going on somewhere, and there will always be a new place to see, a new adventure to experience. I don't know what lies ahead, but my intentions are to make the world knowable to as many people as possible.
There are many reasons for this, and chief among them is the age-old human desire to tell stories. But even more important in my mind is the need to defend the Earth. I could never have foreseen that we would be cursed with such a greedy and ignorant administration as the one that exists now in Washington. They deny the reality of climate change, and they have shown an eagerness to sell off and open to mining and drilling the most precious of our public lands. They are trying to dismantle the system of controls and regulations that protect our air, soil and water. This course of action is morally wrong and physically unsustainable.
Ignorance and greed can and will destroy the fabric and stability of society. I will continue to blog about our planet because I think we need more storytellers, and we need more scientists. I hope we can continue this journey together for a long time!
The post below appeared on August 21, 2017...
Yeah, I was really taking a chance, choosing to stay on the Oregon Coast for the 2017 eclipse. The reason? The fog. And there was a lot of it. To make the long story short, it never really lifted, but we could still see most of the sights through the clouds. I didn't get to see much of the corona, but there were lots of Solar prominences to compensate. It was an awesome experience in the end, but my nails are bitten down to the nubs!
We started out from Florence at 4:40 AM, not wanting to miss a parking spot. There was not a lot of traffic, and we were absolutely thrilled to see parking spaces at Seal Rock State Park. The fog was a concern, though, and the sun was still not at all visible at 8:30.
The crew at Seal Rock was stubborn though. There was some discussion of trying a different spot, but most everyone stayed, hoping for a break in the clouds. It never happened, but the clouds thinned enough that the Sun shown through. I suspect that made things a bit more dangerous, because the clouds made the eclipse glasses almost useless, and UV light could still damage people's eyes. I trusted my cameras to filter things for me (I was shooting with two Panasonic Lumix DMZ FZ70 with a 60x zoom; one on a tripod, the other handheld). I started snapping photos.
At the beginning, the Sun was the show with a couple of sunspots visible, one almost dead-center, and the other near the lower left quadrant.
Despite the warnings, I realized I could get pictures at this point without the filter, so the next couple of pictures are the true color of the Sun: white.
The discontinuities on the right edge of the crescent below are mountains on the Moon splitting up the sunlight.
The crowd at Seal Rock had been chattering away throughout most of the buildup to totality, but there was a sudden hush of shock and awe as the Sun suddenly disappeared, and it was as dark as night.
The Solar prominences glowed pink around the margins of the disk. As noted before, the corona was not visible through the fog.
There was an audible gasp in the crowd as the first streaks of light appeared on the other side of the Moon. The prominences quickly disappeared in the bright shinning light.
And then totality was over as the sky began to lighten up after 1 minute and 25 seconds of darkness. We didn't get to see the stars and planets, but I was not going to complain. What we saw was simply awe-inspiring. I understand that not everybody can drop everything and go across an entire country to see a shadow for less than two minutes, but if you ever have an opportunity, don't pass it up! It's a common experience of humanity to see the Sun blotted out by the Moon, and witnessing one in person can help one understand the myths and legends that grew around eclipses. I literally felt like shouting for the dragon to let the Sun back out of its mouth.
Update: Very pleased that EarthSky posted one of my pictures! http://earthsky.org/todays-image/photos-aug-21-2017-total-solar-eclipse
Saturday, January 27, 2018
A Look Back at Ten Years of Geotripping: Dealing with the Dangerous Rays of Death
One of the greatest thrills of digital cameras is how easily they allow the documentation of celestial events. A 60x zoom is telescope grade, and yet is available on cameras costing less than $400. My history with digital cameras began 18 years ago, and their versatility has allowed me to document a large number of astronomical and meteorological phenomena. 2017 was a culmination as I was able to be in place to witness the total eclipse of the sun in August. But leading up to that day, I had put together a post of the what were to me the most fascinating sky events of my life so far. That post appeared on August 3 of last year...
Dealing with the Dangerous Rays of Death: Singular Solar Events I've Seen
Do you ever look at the sun?
Some advice: DON'T LOOK AT THE SUN! You can destroy your eyes!
Good, now that we have that out of the way, what is this post all about? The sun has been on my mind the last few days. I'm preparing for the final adventure of the summer, and it has a lot to do with the sun, most specifically, the only eclipse to cross the lower 48 states since 1979, the first to cross the country in 99 years, and the last to cross the American West until 2045. I got to thinking about the singular events that I've seen over the years that involve the sun in some way or another.
The sun. A diameter of about 860,000 miles, more than 100 times the diameter of the Earth. About 93,000,000 miles away from Earth. Big enough to hold 330,000 Earths. Containing 99.86% of the mass of the Solar System. The source of energy that makes life possible on Earth.
The most obvious moments that we might pay attention to the sun are during sunrise and sunset. Every one is different and unique. At those times, the sun is at eye level, and the thickness (and dirtiness) of the atmosphere provide a bit of protection for viewing with the unprotected eye. As the sun passes across the horizon, light is split into bright colors of the spectrum, providing a beautiful spectacle. I've probably taken thousands of sunset and sunrise pictures over the years, but here are two of my favorites, a sunset in Newport California a few years ago (above), and sunrise over Lake Rotorua in New Zealand in 2004 (below). To this day I cannot keep straight my internal compass; I couldn't help but think the sun was rising in the west (it wasn't). Lake Rotorua is one of the world's rare geothermal regions with geysers. Hot springs in the lake account for the steam rising off the water.
A difficult phenomena to see related to sunsets is the green flash. It is a sudden flash of greenish light above the sun at the moment of sunset, and it is said to last only a second or so. As the sun dips into the horizon, the layers of the atmosphere will cause some of the sunlight to be refracted, with red and orange on the lower parts of the disk along with green (and rarely blue) across the top.
It takes some very specific circumstances to see the flash, a clear view to a distant horizon, most often along coastlines. I have relatives on the coast of Oregon, so I've had a fair number of chances to try and capture the moment. I may even have succeeded once or twice.
Rainbows are one of the most familiar optical effects associated with the sun. Most everyone has seen them, so it takes some unique circumstances to really set one apart from others. My favorite moment came with a monsoonal storm on the North Rim of the Grand Canyon last year. I was looking down at a rainbow in the depths of the canyon.
One of the more famous places to see beams of light from the sun is in Antelope Canyon, Arizona. A deep slot canyon, Antelope is one of the most popular tourist stops on the Navajo Nation. The sandstone canyon is more than 100 feet deep, and only a few feet wide at the top. One can actually jump across if it were allowed. Tours are offered all day, but one pays a premium around noon for the obvious reason that it's when the sun sends beams of light into the depths of the canyon.
The effect is truly spectacular, although one should be aware that as lonely as these pictures seem, I was shoulder to shoulder with other photographers snapping like crazy.
Another fascinating phenomena occurs when the Moon passes into the Earth's shadow, a lunar eclipse. They are not rare, happening around two times a year, and they can be seen simultaneously across the globe (as long as the moon is visible in the sky).
Lunar eclipses are fascinating to watch, and it is surprising to realize just how much of the sun's light is reflected from the moon. At totality, the moon practically disappears except for some refracted light around the edge of the Earth. Hundreds of stars become visible that weren't there moments earlier.
In a ridiculous age when science has to convince some people that the Earth is not actually flat, a lunar eclipse can help. The Earth casts a circular shadow across the surface of the Moon.
And then there is the opposite number, those events that result from the Moon passing in front of the Sun, a Solar eclipse. Although the Sun is many times larger than the Moon, the Moon is much closer to the earth, and is thus big enough to blot out the sun entirely. Solar eclipses are rarer than Lunar eclipses, and total solar eclipses are rarer still. I've been able to photograph a number of partial Solar eclipses over the years. For me, it is a clumsy affair, trying to hold a filter over the lens while keeping the Sun in the frame, but I've surrendered to the use of a tripod a few times to make it work.
The picture above is one of my favorites because of the huge sunspots that were present during the Moon's transit across the disc of the Sun. If the eclipse occurs when the Moon is farther from the Earth (it has an elliptical orbit), an annular eclipse can occur, in which the Moon doesn't cover the entire disc of the sun. I caught the picture below in 2012.
Zooming in made Mercury a bit clearer (below). Transits of Mercury are not overly rare, occurring in 1999, 2003, 2006, and 2016. Another will take place in November of 2019, but then we will need to wait until 2032 to see another.
The big event of all things Solar is of course a total Solar eclipse. As noted above, it's been decades since one took place in the lower 48 states, and next won't cross my neck of the woods until 2045. I'll be almost 90 years old if I make it that far. I've had the privilege of witnessing one, though, in 1991. It crossed the south end of Baja California at San Jose del Cabo. A small expedition from MJC drove the length of the Baja Peninsula to see the event, one of the great adventures of my life. I didn't get pictures at the time, as the best technology I had was a Kodak Instamatic. The pictures below are from Dr. William Luebke, MJC's retired astronomy professor.
There is nothing quite like the few moments of totality. The sky goes dark, stars and planets become visible, and the ambient temperature plummets (it was summer when we were there, and the temperature dropped from over 100 degrees to 80 or less; it was a relief). The corona of the sun becomes visible, and there may be solar prominences visible as well. We had more than four minutes of totality, more than usual.
It's going to be a zoo in Oregon in a few weeks, as literally millions of people are converging on the region to have a look at this rare event. We will be staying about an hour's drive from the path of totality, so I have no idea if we'll be able to even get to the dark zone through the gridlocked traffic. If we do, I'll be busy getting pictures to share, and if we don't...well...we'll always have Baja.
Dealing with the Dangerous Rays of Death: Singular Solar Events I've Seen
Do you ever look at the sun?
Some advice: DON'T LOOK AT THE SUN! You can destroy your eyes!
Good, now that we have that out of the way, what is this post all about? The sun has been on my mind the last few days. I'm preparing for the final adventure of the summer, and it has a lot to do with the sun, most specifically, the only eclipse to cross the lower 48 states since 1979, the first to cross the country in 99 years, and the last to cross the American West until 2045. I got to thinking about the singular events that I've seen over the years that involve the sun in some way or another.
The sun. A diameter of about 860,000 miles, more than 100 times the diameter of the Earth. About 93,000,000 miles away from Earth. Big enough to hold 330,000 Earths. Containing 99.86% of the mass of the Solar System. The source of energy that makes life possible on Earth.
The most obvious moments that we might pay attention to the sun are during sunrise and sunset. Every one is different and unique. At those times, the sun is at eye level, and the thickness (and dirtiness) of the atmosphere provide a bit of protection for viewing with the unprotected eye. As the sun passes across the horizon, light is split into bright colors of the spectrum, providing a beautiful spectacle. I've probably taken thousands of sunset and sunrise pictures over the years, but here are two of my favorites, a sunset in Newport California a few years ago (above), and sunrise over Lake Rotorua in New Zealand in 2004 (below). To this day I cannot keep straight my internal compass; I couldn't help but think the sun was rising in the west (it wasn't). Lake Rotorua is one of the world's rare geothermal regions with geysers. Hot springs in the lake account for the steam rising off the water.
A difficult phenomena to see related to sunsets is the green flash. It is a sudden flash of greenish light above the sun at the moment of sunset, and it is said to last only a second or so. As the sun dips into the horizon, the layers of the atmosphere will cause some of the sunlight to be refracted, with red and orange on the lower parts of the disk along with green (and rarely blue) across the top.
It takes some very specific circumstances to see the flash, a clear view to a distant horizon, most often along coastlines. I have relatives on the coast of Oregon, so I've had a fair number of chances to try and capture the moment. I may even have succeeded once or twice.
Rainbows are one of the most familiar optical effects associated with the sun. Most everyone has seen them, so it takes some unique circumstances to really set one apart from others. My favorite moment came with a monsoonal storm on the North Rim of the Grand Canyon last year. I was looking down at a rainbow in the depths of the canyon.
Rainbows involve the splitting of white light from the sun into its component colors of the spectrum. Caves and deep slot canyons provide another sort of splitting, that of the sun's energy into a more or less pinhole of light. I was exploring a lava tube in the Mojave National Preserve a few years back. It was dark inside, but there were a few small skylights, and the early afternoon sun came bursting through like a blast from alien phaser.
Another fascinating phenomena occurs when the Moon passes into the Earth's shadow, a lunar eclipse. They are not rare, happening around two times a year, and they can be seen simultaneously across the globe (as long as the moon is visible in the sky).
And then there is the opposite number, those events that result from the Moon passing in front of the Sun, a Solar eclipse. Although the Sun is many times larger than the Moon, the Moon is much closer to the earth, and is thus big enough to blot out the sun entirely. Solar eclipses are rarer than Lunar eclipses, and total solar eclipses are rarer still. I've been able to photograph a number of partial Solar eclipses over the years. For me, it is a clumsy affair, trying to hold a filter over the lens while keeping the Sun in the frame, but I've surrendered to the use of a tripod a few times to make it work.
The picture above is one of my favorites because of the huge sunspots that were present during the Moon's transit across the disc of the Sun. If the eclipse occurs when the Moon is farther from the Earth (it has an elliptical orbit), an annular eclipse can occur, in which the Moon doesn't cover the entire disc of the sun. I caught the picture below in 2012.
And then there are the transits of the planets. These happen when a planet crosses the disk of the Sun. Only two planets can do this, Mercury and Venus, because they are the only planets with orbits that are closer to the Sun than Earth. I've witnessed two of them.
A transit of the planet Mercury took place in May of 2016. I almost missed it because of cloud cover, but they cleared enough for a couple of shots. There was a sunspot as well. In the picture below, the top arrow points to a sunspot. The lower arrow points to Mercury. It is a small planet, only barely bigger than the Moon, and it orbits much closer to the Sun. Such transits are only visible by binocular or telescope (with filters, of course).Zooming in made Mercury a bit clearer (below). Transits of Mercury are not overly rare, occurring in 1999, 2003, 2006, and 2016. Another will take place in November of 2019, but then we will need to wait until 2032 to see another.
The rarest Sun-related event I've ever seen is a transit of the planet Venus. The one I witnessed happened in 2012 (below). Previous transits had been in 1874, 1882, and 2004. The next will not happen until 2117 (in December, if you are planning on watching).
The big event of all things Solar is of course a total Solar eclipse. As noted above, it's been decades since one took place in the lower 48 states, and next won't cross my neck of the woods until 2045. I'll be almost 90 years old if I make it that far. I've had the privilege of witnessing one, though, in 1991. It crossed the south end of Baja California at San Jose del Cabo. A small expedition from MJC drove the length of the Baja Peninsula to see the event, one of the great adventures of my life. I didn't get pictures at the time, as the best technology I had was a Kodak Instamatic. The pictures below are from Dr. William Luebke, MJC's retired astronomy professor.
There is nothing quite like the few moments of totality. The sky goes dark, stars and planets become visible, and the ambient temperature plummets (it was summer when we were there, and the temperature dropped from over 100 degrees to 80 or less; it was a relief). The corona of the sun becomes visible, and there may be solar prominences visible as well. We had more than four minutes of totality, more than usual.
It's going to be a zoo in Oregon in a few weeks, as literally millions of people are converging on the region to have a look at this rare event. We will be staying about an hour's drive from the path of totality, so I have no idea if we'll be able to even get to the dark zone through the gridlocked traffic. If we do, I'll be busy getting pictures to share, and if we don't...well...we'll always have Baja.
The Difference a Year Makes: Liveblogging the "Deluge" (Hint: There isn't one)
This post is both a look back at ten years of Geotripping, but is also an update on snow and precipitation conditions in California right now, and that picture is not pretty. My backyard rain gauge had amassed a mere 1.22" of rain by the beginning of January, and while January had higher than normal precipitation, I only show 4.66" for the rain year, just a bit over 50% of normal (I think we benefited from a few isolated downpours, as Modesto, just 13 miles away is at 3.09"). During the historic drought of 2011-16, three of the dry years were wetter than this.
I walked the Tuolumne River Parkway Trail today, and for the first time in weeks I could see the Sierra Nevada, the peaks that loom high above Yosemite Valley. The sun reflected off a snowpack that was far different than it was a year ago. The snowpack is only 30% of normal (see below). It's late January and there are a few ski resorts that haven't even opened yet (if they'll even open at all).
Source: http://cdec.water.ca.gov/snowapp/sweq.action |
If there is any bright spot in this dismal year it is California's reservoirs. Because of the ample rain and snow last year, most of the reservoirs are at healthy levels, more than 100% of normal (see below). One prominent exception is Oroville Reservoir, which was lowered drastically to allow repairs to the spillways that failed during the height of the storms last year. There is at least some comfort to know that we have some resources to weather another drought, at least for a few years. I would have preferred a few wet years to help replenish our depleted groundwater reservoirs. That is a lasting effect of the drought that may not be fixed any time soon.
Source: http://cdec.water.ca.gov/cgi-progs/products/rescond.pdf |
I've been going through the Geotripper archives to select some of my favorite blog posts of the last ten years. The first half of 2017 was dominated by my observations of the extraordinarily wet year and the flooding, which I called "Liveblogging the Deluge". I wrote dozens of posts all through the first half of the year, and it was hard to pick any particular ones to illustrate here, so I settled on the one I wrote exactly one year ago. It involved the post-mortem of the first of the major atmospheric river storms that battered the state. Many more were to come...
Thursday, January 26, 2017
The atmospheric river storms of January have finally subsided, and we are looking at kind of a new landscape across California. We had a couple of sunny days, so we headed up the highway to have a look at Don Pedro Reservoir on the Tuolumne River coming out of Yosemite. When we visited on January 5, the lake stood at 786 feet, which translates to 76% of capacity. That was 114% of normal for this time of year, which was a relief after five years of intense drought.
Don Pedro Reservoir on January 26 after two atmospheric river storms, elevation 813 feet (90% of capacity). |
When we arrived yesterday, the lake stood at 813 feet, or 90% of capacity, which is 133% of normal. It is only 17 feet below the level of the dam. It could have been higher, but the dam operators have been maintaining constant outflows in the range of 7,000-9,000 cubic feet per second, a level that is just short of flood stage. Had they not done this, the lake could have overflowed and flooded downstream urban areas as happened in 1997.
Source: http://cdec.water.ca.gov/cgi-progs/products/rescond.pdf |
Source: http://cdec.water.ca.gov/cgi-progs/products/rescond.pdf |
Tuolumne River in Waterford, about 8,000 cubic feet per second |
My rain gauge has been active. My friends in more humid regions may snicker a bit when I talk of how we've had 7.38 inches of precipitation in January. That might not seem like all that much but in 25 years of recording rainfall in Waterford, only two had greater amounts, 7.58" in 1995, and 8.60" in 2011. We've had a year where that was the total for the entire season (7.26" in 2014). We've already passed the total rainfall normally received in an average year (14.69" so far compared to 13.92" average for the last 25 years).
But the real story? The snowpack.
At the height of the drought, we had a snowpack that was 5% of normal. 5%! It was both unbelievable and appalling.
Source: http://www.sacbee.com/news/state/california/water-and-drought/article124305504.html |
And the snow kept falling! The second atmospheric river storm system brought even more snow, and as of today, the snowpack is nearly 200% of normal. If the trend continues (there is NO guarantee of this), we could be on track for a record snowpack. I don't consider it likely, but it would be nice to start recharging the groundwater aquifers that have been severely depleted in recent years.
Source: http://cdec.water.ca.gov/cgi-progs/products/swccond.pdf |
The record snowpack should not be seen as evidence that global warming isn't happening. Average temperatures are defiinitely up and have been for several decades. The thing is, snow is snow whether the temperature is 15 degrees or 30 degrees. A not-at-all unusual heat wave could undo the progress in the snow levels. The sky spigot could turn off. After the record flooding of 1997, February and March both provided less than a quarter inch of rain over the entire month. And the drought will never be truly over, as demand outstrips supply even in plentiful years. And little is being done to replenish declining groundwater aquifers.
All in all, though, I'm happier to have plentiful rain rather than crippling drought!