ゴミが先か、人間が先か

滅亡へのカウントダウン(上): 人口大爆発とわれわれの未来 (2013/12/19) アラン ワイズマン 商品詳細を見る

以前ご紹介したCountdownという洋書が『滅亡へのカウントダウン』として翻訳されたようです。

福岡伸一氏絶賛!
「地球が扶養できる生物の数には限界がある。こと人間の数に関しては、すでに、はるかに限界を超えている。過剰な水素が一気に爆発するように、カタストロフの日は近い。そのとき地球に何が起きるのか。そうならないため今できることは? 本書の中にその答がある」

人口が地球の収容限界を超えるとき、いったい何が起きるのか? 世界的ベストセラー『人類が消えた世界』の著者が放つ衝撃のレポート。

すでに70億人に達し、今世紀中には100億人を超えると予想される世界人口。4日半ごとに100万人の割合で増え続ける人類は、地球環境にいかなる影響を及ぼしているのか?

加速する温暖化、続発する異常気象、生物多様性の喪失――こうした環境問題の根本に過剰な人口があるのだとしたら、すべての文化圏に属する人が納得できる人口抑制の方法はあるのだろうか? さらに、絶え間ない人口拡大と成長に依存しない新しい経済システムを設計することは可能なのか? 果たしてわれわれは、今後も存続していくことができるのだろうか?

世界的な環境ジャーナリストが中国、ニジェール、インド、ヴァチカン、日本など20余カ国を旅しながら考える。人口学者、生態学者、経済学者、宗教指導者ら、あらゆる人々の肉声から見えてくる未来とは? 人類が直面する今世紀最大の問題に迫る必読のノンフィクション。
(序文「日本の読者へ」を特別収録)

この出版で思い出したのが雑誌Natureでゴミ問題を取り上げた記事。経済が発展し人口が増えるということはゴミも増えるということです。ゴミのピークが来世紀に起こるという予測を立てていました。現状、原因、将来の予測、対応策ときれいに構成されている読みやすい記事です。peak oilならぬpeak wasteの予測グラフはリンク先でご確認ください。

Environment: Waste production must peak this century
Daniel Hoornweg, Perinaz Bhada-Tata& Chris Kennedy
30 October 2013
Without drastic action, population growth and urbanization will outpace waste reduction, warn Daniel Hoornweg, Perinaz Bhada-Tata and Chris Kennedy.

As city dwellers become richer, the amount of waste they produce reaches a limit. Wealthy societies tend to curb their waste. So as living standards around the world rise and urban populations stabilize, global solid-waste generation will peak.

Just when is difficult to predict. But by extending current socio-economic trends to 2100, we project that 'peak waste' will not occur this century. Unless we reduce population growth and material consumption rates, the planet will have to bear an increasing waste burden.

都市生活がゴミの主要因ですが、アメリカのゴミ排出量が日本の３倍もあるというのは驚きですね。日本での生活でもゴミが多いと思えますから。

Urban problem
Solid waste is mostly an urban phenomenon. In rural communities there are fewer packaged products, less food waste and less manufacturing. A city resident generates twice as much waste as their rural counterpart of the same affluence. If we account for the fact that urban citizens are usually richer, they generate four times as much.

As urbanization increases, global solid-waste generation is accelerating. In 1900, the world had 220 million urban residents (13% of the population). They produced fewer than 300,000 tonnes of rubbish (such as broken household items, ash, food waste and packaging) per day. By 2000, the 2.9 billion people living in cities (49% of the world's population) were creating more than 3 million tonnes of solid waste per day. By 2025 it will be twice that — enough to fill a line of rubbish trucks 5,000 kilometres long every day.

Together, the member countries of the Organisation for Economic Co-operation and Development (OECD) are the largest waste generators, producing around 1.75 million tonnes per day. This volume is expected to increase until 2050, owing to urban population growth, and then to slowly decline, as advances in material science and technology make products smaller, lighter and more resource efficient.

Some countries generate more waste than others. Japan issues about one-third less rubbish per person than the United States, despite having roughly the same gross domestic product (GDP) per capita. This is because of higher-density living, higher prices for a larger share of imports and cultural norms. Waste quantities worldwide can also vary seasonally, by up to 30%, as horticultural and food wastes fluctuate. For example, household waste volumes double in the week after Christmas in Canada.

将来予測について書かれている部分ですが、文字だけ読んでみてからグラフを見てみると英文読解力想像力を試せそうです。まあ、自分は最初にグラフを見てしまいましたが（汗）

Extending those projections to 2100 for a range of published population and GDP scenarios shows that global 'peak waste' will not happen this century if current trends continue (see 'When will waste peak?'). Although OECD countries will peak by 2050 and Asia–Pacific countries by 2075, waste will continue to rise in the fast-growing cities of sub-Saharan Africa. The urbanization trajectory of Africa will be the main determinant of the date and intensity of global peak waste2.

Using 'business-as-usual' projections, we predict that, by 2100, solid-waste generation rates will exceed 11 million tonnes per day — more than three times today's rate. With lower populations, denser, more resource-efficient cities and less consumption (along with higher affluence), the peak could come forward to 2075 and reduce in intensity by more than 25%. This would save around 2.6 million tonnes per day.

対応策の部分ではゼロエミッションの試みの都市としてサンフランシスコが挙げられています。また、川崎市の取り組みも紹介されていました。

How can today's situation be improved? Much can be done locally to reduce waste. Some countries and cities are leading the way. San Francisco in California has a goal of 'zero waste' (100% waste diversion by reduction and recycling) by 2020; already more than 55% of its waste is recycled or reused. The Japanese city of Kawasaki has improved its industrial processes to divert 565,000 tonnes of potential waste per year — more than all the municipal waste the city now handles. The exchange and reuse of materials connects steel, cement, chemical and paper firms into an industrial ecosystem3.

一番の問題はこれから大きく発展していくアフリカなどの国々のようですが、ライフスタイルそのものの見直しを、食品から建物に至るまで幅広い領域で実践していく必要があるようです。

Reducing food and horticultural waste is important — these waste components are expected to remain large. Construction and demolition also contribute a large fraction by mass to the waste stream; therefore, building strategies that maximize the use of existing materials in new construction would yield significant results.

The planet is already straining from the impacts of today's waste, and we are on a path to more than triple quantities. Through a move towards stable or declining populations, denser and better-managed cities consuming fewer resources, and greater equity and use of technology, we can bring peak waste forward and down. The environmental, economic and social benefits would be enormous.


下記のリンクは記事で触れられていたWorld Bankによるゴミ問題の報告書です。

What a waste