Are we running out of clean water? - Balsher Singh Sidhu

912,194 views ・ 2018-12-06

TED-Ed


Please double-click on the English subtitles below to play the video.

00:07
From space, our planet appears to be more ocean than Earth.
0
7088
4687
00:11
But despite the water covering 71% of the planet’s surface,
1
11775
4056
00:15
more than half the world’s population endures extreme water scarcity
2
15831
5131
00:20
for at least one month a year.
3
20962
2714
00:23
And current estimates predict that by 2040,
4
23676
3059
00:26
up to 20 more countries could be experiencing water shortages.
5
26735
5226
00:31
Taken together, these bleak statistics raise a startling question:
6
31961
4272
00:36
are we running out of clean water?
7
36233
3020
00:39
Well yes, and no.
8
39253
2259
00:41
At a planetary scale, Earth can’t run out of freshwater thanks to the water cycle,
9
41512
5022
00:46
a system that continuously produces and recycles water,
10
46534
3875
00:50
morphing it from vapour, to liquid, to ice as it circulates around the globe.
11
50409
5585
00:55
So this isn’t really a question of how much water there is,
12
55994
3203
00:59
but of how much of it is accessible to us.
13
59197
3418
01:02
97% of earth’s liquid is saltwater,
14
62615
3305
01:05
too loaded with minerals for humans to drink or use in agriculture.
15
65920
4585
01:10
Of the remaining 3% of potentially usable freshwater,
16
70505
4089
01:14
more than two-thirds is frozen in ice caps and glaciers.
17
74594
4479
01:19
That leaves less than 1% available for sustaining all life on Earth,
18
79073
4801
01:23
spread across our planet in rivers, lakes,
19
83874
2697
01:26
underground aquifers, ground ice and permafrost.
20
86571
4581
01:31
It’s these sources of water that are being rapidly depleted by humans,
21
91152
4612
01:35
but slowly replenished by rain and snowfall.
22
95764
3333
01:39
And this limited supply isn’t distributed evenly around the globe.
23
99097
4339
01:43
Diverse climates and geography provide some regions
24
103436
3439
01:46
with more rainfall and natural water sources, while other areas have geographic features
25
106875
5277
01:52
that make transporting water much more difficult.
26
112152
3456
01:55
And supplying the infrastructure and energy it would take
27
115608
3087
01:58
to move water across these regions is extremely expensive.
28
118695
4710
02:03
In many of these water-poor areas, as well as some with greater access to water,
29
123405
4692
02:08
humanity is guzzling up the local water supply faster than it can be replenished.
30
128097
4916
02:13
And when more quickly renewed sources can’t meet the demand,
31
133013
3557
02:16
we start pumping it out of our finite underground reserves.
32
136570
4034
02:20
Of Earth’s 37 major underground reservoirs, 21 are on track to be irreversibly emptied.
33
140604
7339
02:27
So while it’s true that our planet isn’t actually losing water,
34
147943
3655
02:31
we are depleting the water sources we rely on at an unsustainable pace.
35
151598
5057
02:36
This might seem surprising –
36
156655
1577
02:38
after all, on average, people only drink about two liters of water a day.
37
158232
4458
02:42
But water plays a hidden role in our daily lives, and in that same 24 hours,
38
162690
5339
02:48
most people will actually consume an estimated 3000 liters of water.
39
168029
5143
02:53
In fact, household water – which we use to drink, cook, and clean –
40
173172
4757
02:57
accounts for only 3.6% of humanity’s water consumption.
41
177929
5212
03:03
Another 4.4% goes to the wide range of factories
42
183141
4291
03:07
which make the products we buy each day.
43
187432
2863
03:10
But the remaining 92% of our water consumption is all spent on a single industry:
44
190295
5805
03:16
agriculture.
45
196100
1570
03:17
Our farms drain the equivalent of 3.3 billion
46
197670
4026
03:21
Olympic-sized swimming pools every year,
47
201696
4104
03:25
all of it swallowed up by crops and livestock
48
205800
2783
03:28
to feed Earth’s growing population.
49
208583
2983
03:31
Agriculture currently covers 37% of Earth’s land area,
50
211566
4152
03:35
posing the biggest threat to our regional water supplies.
51
215718
3318
03:39
And yet, it’s also a necessity.
52
219036
2468
03:41
So how do we limit agriculture’s thirst while still feeding those who rely on it?
53
221504
6214
03:47
Farmers are already finding ingenious ways to reduce their impact,
54
227718
3958
03:51
like using special irrigation techniques to grow “more crop per drop”,
55
231676
4806
03:56
and breeding new crops that are less thirsty.
56
236482
2905
03:59
Other industries are following suit,
57
239387
2028
04:01
adopting production processes that reuse and recycle water.
58
241415
4569
04:05
On a personal level, reducing food waste is the first step to reducing water use,
59
245984
5292
04:11
since one-third of the food that leaves farms is currently wasted or thrown away.
60
251276
4859
04:16
You might also want to consider eating less water-intensive foods
61
256135
3764
04:19
like shelled nuts and red meat.
62
259899
3109
04:23
Adopting a vegetarian lifestyle could reduce
63
263008
2538
04:25
up to one third of your water footprint.
64
265546
3128
04:28
Our planet may never run out of water,
65
268674
2260
04:30
but it doesn’t have to for individuals to go thirsty.
66
270934
3043
04:33
Solving this local problem requires a global solution,
67
273977
3546
04:37
and small day-to-day decisions can affect reservoirs around the world.
68
277523
4901
About this website

This site will introduce you to YouTube videos that are useful for learning English. You will see English lessons taught by top-notch teachers from around the world. Double-click on the English subtitles displayed on each video page to play the video from there. The subtitles scroll in sync with the video playback. If you have any comments or requests, please contact us using this contact form.

https://forms.gle/WvT1wiN1qDtmnspy7