Gray mentioned to me that he had made a promise and we had an appointment. It being a Saturday afternoon, a college football game was underway at the University Stadium. I had already spotted it on the northern side of town and although the players were probably padded giants they looked like gnats on a pond from up here. The game had just reached half time and the players were streaming off the field, so Gray swooped down to a lower altitude, stalled the glider over the field, made it nod then dramatically swoop away to the right. I could not be certain but it looked like every face was looking up at us. The movement lost us considerable height and Gray looked around for thermals. The sky was still clear and it was not obvious if there were any natural thermals around on this cold day, but that did not concern Gray. He headed to the out of town shopping area and picked up some hot air rising from the car parks and malls and we soon regained most of our altitude.
We were just in time. The two military planes that we had seen earlier were heading straight for town and did a dramatic low level fly past over the stadium. The crowd were getting their half time show from us.
Over the pitch
All too soon Gray said that we didn’t have that much altitude left to play with. I was sorry not to head out in to the country, but for a first flight it had been a full event. We circled a couple more times over Brookings and I could see down at the excavations going on at the airport. Gray said we would not land on the runway, instead we would find some grass. He chose a square just to the right of the runway from which we had taken off. It was a pocket handkerchief sized plot and hindered by some orange temporary fencing held in place by tall metal rebar posts. Gray did not want to overshoot the grass to the taxi way beyond so tried to come in as low as possible above the fence to maximize the length of grass. He timed his approach perfectly and the wheels must have passed inches above the posts, then we bumped harshly on to the grass and almost immediately came to a halt.
I detached myself from the seatbelts and waited to Gray to guide me out of the plane; I could not conceal the broad grin on my face. I thanked him profusely. He, with his usual humility said not at all, it was a pleasure.
Having another geographer flying the glider meant we could focus on things which interested our geeky selves. Gray described the layout of Brookings city, and the planes. I tried to orientate myself; I could see a long line of wind turbines to the east. I wondered if they were just over the state line in Minnesota. To the west there were no other features to determine. South Dakota is known for the Black Hills and the famous carvings of US Presidents on a rock face, but they were nearly 350 miles to the west; well over the horizon even at this altitude. All I could discern were just fields.
But I noticed that within the regular grid iron pattern of fields and roads there were anomalies. The river channels and creeks that have existed for millennia across the whole of the Plains have no respect for human regularity. Either the rivers are still bending this way or the other, or where they have been covered of rerouted, the ghosts of former channels are still present in the shadows from the low fall sun, or changes in soil and vegetation colour in the fields.
The regularity of the fields is a common feature of so much of the US. While it is monotonous or boring, it is the legacy of an amazing principle that was put in motion as early as the 1780’s, a few years after the declaration of independence. The Public Land Survey System was a plan to subdivide the new territories west of the Appalachian Mountains for sale and planning purposes. The result was you see the squares of the fields and plots, and the roads which have to obey the lines drawn up which makes so much of the central part of the US have such a regular land pattern. If people wonder why the most advanced nation on the surface of the earth still insists on using the Imperial System of measurement, the PLSS is one of the largest reasons for this. Plots were marked off in miles, and the distances between road junctions are multiples of miles. Any use of kilometres would be nonsensical in this rigid framework.
Gray climbed into the back seat and closed up the windows – all but one which he used to signal to his ground crew. He had a brief word to the control tower on his portable radio, then, all signals given, the tow plane started to move forward and the rope took up the slack. All at once we were moving forward and the glider, which had been tilted to one side so a wing was touching the runway, levelled off and picked up some speed. The aircraft rose gently in front of us and we followed a few seconds later. Losing the noise of the wheels on the ground, all we had with us was the engine noise in the plane up front. Our ascent was shallow and we circled several times over the runway to gain altitude. I could start to appreciate the land below, both the tight urban landscape of Brookings itself, and then the never ending prospect of fields stretching out over the Great Plains.
Onwards and upwards we went for many minutes. Eventually, Gray spoke to me through the headphones and asked me to get ready to detach the tow rope. On his command I pulled the big wooden knob towards me, and we felt a sharp jolt as the glider was sent off on its own trajectory and the plane dropped away quickly, retracting its rope and heading for the runway.
We were there on our own and the only accompanying noise came from the roar of the wind and my quickened breathing. It was spectacular. For a geographer to have the opportunity to glide like a bird of prey over the country, and to help identify where to go next, was fantastic. Yes, we can all look at Google Earth these days, but it does not give you that experience of being in the atmosphere above the areas you are observing. Yes we can fly in planes, but they are on set routes, often above the clouds, and pushy stewardesses insist on you closing the blinds to allow others to watch fantasy films when the majesty of real life is passing below you.
Having never worked in a hangar, I hung back while Gray cleaned his windscreens, tested the flaps, ensured all the wires and controls were operating, and then he released the cables that were holding the glider still in the hangar and asked me to help guide the vehicle out into the open.
I took hold on one wing while Gray steered from the middle. I was amazed just how light and controllable the glider was. We steered it gently through the doorway and out onto the road. A friend of Gray’s turned up – he was a research assistant at the university and often helped Gray out as groundcrew. Then from an aircraft parked up behind us, another guy stepped out and as we shook hands, Gray explained that this was to be our pilot and he had just emerged from our tow plane. We worked together to run the glider over to the main runway at Brookings. At least it was the main runway (12) when we used it. The usual main runway was being completely dug up, extended and resurfaced.
It took a while to sort out the tow plane so Gray decided the best place for me was in the cockpit. He allowed me to sit in the front seat, strapped me in, closed the windows then returned to the tow plane to walk a rope back to the glider and attach it to the nose. I took the opportunity to recce the instruments in front of me. It all looked remarkably simple. A basic altimeter on the left, some gauges to measure how quickly the glider is rising or falling, the variometer, the airspeed indicator, and something to monitor the banking and rolling and tilting that the glider might do. Taking centre stage in the middle of the dashboard was a large wooden knob. I avoided touching anything and sat patiently but totally excited waiting for this new experience.
Preparing for take off
We also had a wander around the botanical gardens. Although small, it was in full colour – the fall was probably in its finest week before the snow which had threatened earlier in the week finally took hold and made the leaves drop. It was getting close to lunch time by now and Gray had a surprise for me, but first we decided to eat and met up with his wife at the town library. The strip we had spent most time on so far was in fact just the main road out of town and because it was close to the university campus, had a range of cafes and boutique shops. The real down town was that one Main Street with the bank and hotel and all the other important buildings. The library was tucked at the back of this. When we emerged, Gray looked up at the sky; which was almost completely blue, and said “I think we are going to get a good view.”
We drove a mile or so past a small industrial estate south west of town and drew up at the entrance to Brookings Airfield. No commercial flights come in and out but it had a bustle of industry which you do not see in small airfields in the UK. Plenty of small two-seater planes, a helicopter or two, and many large hangers were scattered around. Gray drove to one of these hangars and unlocked a small door, stepping inside to start up the mechanism to open the larger hangar doors, which rolled up into the roof. Inside were a bunch of boys’ toys. Several antique and vintage cars, another biplane and, taking up most of the central space, a fixed wing glider. This was Gray’s pride and joy – he had been a pilot for many years. In fact he had told me of a trip once to the UK where he had flown – turned out he had been at a gliding club on the North Downs less than 20 miles from my home.
We’d chatted to a couple of guys dressed up in old leathers who were looking at their own valued toy at the other end of the hangar. It was an old fighter plane – I was never told whether it was an original refurbished one or a modern remake, but it looked the part. It was apparently one of the US Marine Fighter Squadron, and it roared into life and was taxied out into the open air, round several hangars before taking off. A second biplane went up in the air while Gray prepared his glider.
Gray’s pride and joy
The weekend was fast approaching and I had one more day of work on the Monday to finalise everything before I caught the overnighter back to London from Dallas. Gray kindly invited me to join him for the Saturday and he would show me some of the countryside. He lived not in Sioux Falls but in the town of Brookings, about a 50 mile drive up the I29 to the north. I drove steadily up the Interstate; I always do despite the roads being huge and empty, the troopers have little else to do but find an excuse to book a foreigner for speeding. I29 ran along ground which was higher than that to the west, and I began to realise the humpy bumpy terrain around EROS was part of a fat ridge, barely 100m above the rest of the plain, but enough to make a difference in an area of little relief. Only the Sioux River cut through it.
I took the Brookings exit and drove along a main road into town; it was the usual anonymous mix of gas stations, eateries and motels. Then they dissolved away and I was in a pleasant urban landscape. Gray met me at his favourite coffee shop and, since I had skipped breakfast that morning, we had a muffin and cappuccino. Gray was a calm, thoughtful guy, and he looked totally at ease here; this was his usual habitat. He said he preferred the small town feel of Brookings to Sioux Falls, but it was no hick town. Brookings was the seat of the State University of South Dakota so had a sizeable student body, as well as the staff, and had attracted in a wide range of people, including several of Gray’s colleagues from USGS. It also had a number of art galleries and museums; more than you would expect for a town of barely 20,000 permanent residents. We visited one, the Agricultural Heritage Museum. When I had been a schoolkid in Liverpool we had spent a couple of terms learning about American history which included a big part about the enclosure of the Great Plains and the life of the homesteader. The grainy old black and white photos gave a rather bleak picture of life out here, and there was no denying it was tough, but this museum had brought it to life with full colour exhibits. Everything was here from the life of a South Dakotan from the 1850s to the Second World War. As well as scrupulously restored farm equipment, from mammoth traction engines and tractors to ploughs and harvesters, there were all the domestic items; mangles, cleaning brushes, preserving jars, beds, chairs, and most revealing, photographs, letters and mementoes of the people who had lived through this period. As well as the glass cabinets and mounted exhibits, rooms had been set up as an example of how all these pieces came together in the draughty old log cabins that people lived in out on the plain. Apart from the fact the artefacts were in pristine polished conditioned, you could imagine the family had just stepped out for a moment for a walk.
The days passed quickly at EROS, and I enjoyed the new surroundings and the concentration I was able to muster to look at one piece of work. Gray set me up at a desk that was currently vacant, and had the luxury of a window on to the east of the vast office block. From my window two huge golf balls loomed, containing earth observation receivers that were downloading data from satellites passing overhead. The grass was neatly cut and the drains and culverts, the clipped trees and shrubs made it a pristine parkland. It was still close to nature and I would sometimes glance out to see an eagle soaring overhead. Once I saw three large brown birds. At first I struggled to recognise them; they reminded me of some of the larger birds I knew from African safaris. A colleague of Gray who was sharing my office seemed surprised I did not recognise them as they were wild turkeys. I was used to turkeys being fat waddling farmyard creatures with garish plumage and wattles and seemingly completely paranoid about the world. No doubt with good reason as they almost all end up on someone’s dinner table.
These birds were pensive, yes, but also deliberate. They strolled across the clipped grass, pecking at whatever they could find. And they looked like real birds rather than lumps of meat with feathers. They had the main features of their domestic cousins, the long blue necks and wattles, but their bodies were much more streamlined and with the plumage more akin to pheasants than turkeys, with black backs but brown under feathers and a black and white pattern on their wing tips.
Gray took me over to this parkland area one afternoon after lunch. There was still a stiff breeze but the sun was out and as long as you kept walking you avoided hyperthermia. The EROS estate included a lake and wildfowl area. I had noticed how South Dakota was not just cultivated fields and cattle ranches; there was significant wild land here. Sometimes it might only be a small patch in the corner of the farm where a creek meandered so much no mechanised farm equipment was able to get in. As well as those there were plenty of reserves. I’d also noticed that when I arrived at Sioux Falls, in fact when I was in Dallas, that many of the people coming to South Dakota were hunters. They flew with their dogs, they were travelling in camouflaged fatigues, and when my suitcase came round the carousel in Arrivals, it was accompanied by plenty of large long metal cases carrying shotguns. South Dakota was a huntin’ an’ a fishin’ state and when
driving back and forth to EROS I did see some guys (they were all men) stalking across the fields towards a clump of woodland.
For the next few days life became surprisingly routine. For someone who either works from home or travels with a suitcase, the idea of commuting to an office every day is anathema. But for a week it was a change for me, and while I took the same route up to EROS in the mornings, I tried to vary my route home and orientate myself around Sioux Falls a bit more.
It is not a massive city by American standards, the city itself has a population of about 150,000 but given the rural nature of South Dakota, the metropolitan area is about 1/3 of the entire population of the state. And like all American cities, especially those set in the wide open spaces of the Great Plains, it sprawls. The original settlement grew up around the falls, and the railroad had a large depot on the east bank from which several lines converged. Warehouses and Main Street grew up on more on the west bank, but at the start of the 20th century the town was laid out in a typical grid iron section, thrown out only by the various rivers and railroads that curved unplanned.
Higher class suburbs were perched up on the bluffs above the Sioux River, and the grand Cathedral towers over the falls. Although only 90 years old it looks like it has commanded the city since Medieval times. Only the crispness and lack of wear of the masonry belies its 20th Century roots. Many other grand houses cluster around the cathedral in tree lined streets, but those lovely avenues, mature and settled stretch many streets west of the small downtown area. The downtown too has been through a regeneration and a couple of streets are now form the hub of nightlife in the city – at least for the young and/or groovy. For the more suburban or small town amongst the population, the big boulevards and the junctions around the interstates provide all they need; those chain restaurants and fast food joints which I have little time for. I was advised that there was the best place for me to eat near the hotel was a shopping mall, the Empire. I did spend an evening or two wandering round and yes the food was cheap but the place was soulless. The only one of the chains that offered me something a bit more special was the Olive Garden. I got strange stares from the drivers who passed by as I walked to this restaurant; it was only about half a mile, just across the Sioux River where it started bending round towards the Falls and the downtown area. Although the nights were freezing, I would pause on the bridge looking at the icy water barely discernible in the blackness, and think of its journey. It came from the north into Sioux Falls, does a huge S bend which means in the downtown area it is heading north once more, then becomes the state boundary between South Dakota and Iowa down to Sioux City, where it joins with the Missouri and on to merge with the Mississippi just north of St Louis. I’d seen the Mississippi when I had travelled to Mardi Gras, first crossing the massive iron bridge at Baton Rouge and then on the waterfront of New Orleans. From there the waters head a further 100 miles in a “Crow’s Foot” Delta, so called because of the shape of all the tiny channels spreading like the toes of a bird into the Gulf of Mexico. Looking down from the bridge I could not help to marvel at where all those little molecules of water had ahead of them.
Then I was startled by a Harley Davison, felt how cold it was and hurried back to my centrally heated suite.
Maybe the thought of what is to all intent and purpose like a library of satellite images is not exciting to you, but it should be. I know I was being all nerdy, but the thought should enter your head that this room contained the history of the earth since the 1960s, and not just a selective biased account from a bunch of opinionated historians, but a systematically collected dataset that uniformly recorded the reflectance of the earth’s surface for many years. To interpret the whole dataset would take longer than life itself has been on the planet, and the archive grows faster than anyone can absorb it, but to know it is there to be referred to is mind blowing. Snapshots of life on earth are all there – the seasons in every landmass, the swirling weather systems, the human footprint ever growing, the disasters, the ebbs and flows, the stases.
Well it blows my mind.
After the tour and some more work, I knocked off a little early as my energy levels had flagged with jetlag, but I thought some fresh air would be good for me before the sun went down. When I came out of the building, I realised the snow had vanished but there were still grey skies and bitterly cold winds, and I put the heater on full blast in the car as I drove back to the city.
Some of the earliest satellite imagery exists in these folders
EROS Data centre is the location of possibly the largest archive of satellite imagery in the world. It was built in the early 1970s when satellite imagery was starting to be collected routinely at the global scale, and one of the USA’s most ubiquitous sources of satellite imagery had been Landsat. I had used it ever since I learnt how to be a remote sensor in the early 1990s. They chose Sioux Falls because they wanted a location which was relatively central to the North American continent to capture the data and download it as the satellites passed overhead. Not only did they download the imagery, but they archived it, and copied it for others to use. I remember waiting weeks for data to arrive on large spools, then tape cassettes, then CDs and DVDs. Now mostly it can be downloaded from the internet.
The storage of all those data was a massive challenge to EROS – especially since those satellites kept on just collecting day and night (even at night you could obtain radar and thermal images). Underneath the building a basement capable of resisting a nuclear explosion was created and Gray took me down there as part of my tour. Big parts of it were now empty, but at one time, Gray said, he could remember when every inch was covered in shelf after shelf of cassettes or spools. Now, he joked, we might as well set up some bowling alleys down here. Later he took me upstairs and looked through bullet proof glass at a large room which contained just two large supercomputers. They now contained many times more data than the large basement had ever held in the 1990s.
Back down in the basement, though, was a fascinating archive of the oldest imagery. There were plastic and metal canisters that contained original film from the early satellites, including from US surveillance forays of Russia and China with the Corona satellite. The images were parachuted back to earth on film negatives. Along another row we came across envelopes of the original Landsat MSS imagery again with negatives in. Gray knew his way around many of these shelves, he was an old remote sensing hand and had spent many an hour searching for imagery he wanted along the aisles. But when I looked up and down the shelves I saw they disappeared several hundred feet off into the gloom. Even now, the physical archive was enormous, and the USGS had not got around to digitizing the whole lot.
Archive stretching into the distance