????美國環境保護署(Environmental Protection Agency)擬定的減少碳排放提案正在引發一場關于氣候變化的激烈辯論。但有一點是明確的：企業需要向投資者更加詳盡地解釋它們面臨的氣候變化相關風險，以及它們正在采取的管控措施。

????加州近期的大干旱和歐洲的洪水提醒我們，極端天氣事件正變得越來越嚴重，越來越頻繁。根據慕尼黑再保險公司(Munich Re)提供的數據，天氣事件占2013年自然災害損失的90%，共造成1,200多億美元的損失。該公司估計，2012年，氣候事件對美國和歐洲經濟的總體影響均超過5萬億美元，占各自國內生產總值(GDP)的30%以上。

????除了監管機構以外，投資界也已經意識到了這種威脅。投資人正在要求公司披露更多關于氣候事件風險的信息，以及碳排放的預期成本。

????身處多種行業的公司——不僅僅是保險公司和碳排放密集型企業——正在被要求披露它們管控這些長期問題的措施。這些企業未來的資金成本在某種程度上將取決于它們給出的答案。

????不幸的是，太多的企業仍然只為投資者及其他利益相關者提供各自面臨風險的部分圖景。在闡述它們如何減輕這些風險的時候，這些企業的解釋是不完整的。

????公司部門正在非常敏捷地滿足投資者對環境友好型資產不斷增長的需求。私營公司發行的綠色債券（這類債券的所籌資金用來資助有利于環境的資本投資）急劇增長。據標準普爾公司(Standard & Poor’s)估計，這類債券的規模今年很可能翻一番，達到200億美元左右。

????但事實證明，就向投資者提供更廣泛的氣候和碳排放相關風險的可靠信息而言，許多企業的動作要慢得多。

????氣候風險，以及碳定價的影響，將導致公司面臨直接和間接風險。從生產到流通和銷售，這類風險可能會影響公司的整個價值鏈。洪水和暴風往往會打亂供應商的部署，使得制造流程陷入混亂，還可能抑制消費。

????從長遠來看，極端天氣會以意想不到的方式損害企業的盈利能力和資產估值。不重視這些風險的公司可能會承受巨大壓力，并且很難靈活地管控它們面臨的風險。

????公司通常很注重披露碳排放法規施加給它們的直接負債，特別是為獲得排放交易計劃要求持有的碳排放許可證而支付的凈成本。這些成本的重要性無需贅言，盡管碳排放信用額的價格最近有所跌落，但隨著時間的推移，這些成本很可能將繼續增長。但很多公司忽視了一項正在沿著供應鏈傳遞，或者正在改變產品和服務終端需求的碳負債成本，而這項成本可能要大得多。

????The Environmental Protection Agency’s proposed regulations to reduce carbon emissions are generating heated debate about climate change. But one thing is clear: companies need to do much more to explain to investors the climate-related risks they face and how they are managing them.

????Extreme weather events appear to be getting more severe and more frequent, as the recent drought in California and floods in Europe reminded us. Weather events accounted for 90% of natural catastrophe losses in 2013, causing over $120 billion of losses, according to reinsurance company Munich Re. In 2012, the overall effect of climate events on the US and European economies is estimated at more than $5 trillion for each region, or over 30% of their GDP.

????The investment community – along with regulators – has woken up to this threat. It is demanding more information from companies about their exposure to climate events, as well as the prospective cost of their carbon emissions.

????A wide range of businesses – not just insurers and carbon intensive corporations – are being pressed to demonstrate how they are managing these long-term issues. Their future cost of capital will in part hinge on the answers they give.

????Unfortunately, too many businesses still provide investors and other stakeholders only a partial picture of the risks they face. And they offer an incomplete explanation of how they are mitigating these exposures.

????The corporate sector is nimble at meeting growing investor demand for environmentally-friendly assets. Private sector companies’ issuance of green bonds, which fund environmentally beneficial capital investment, is growing rapidly. According to Standard & Poor’s, it is likely to double this year to around $20 billion.

????However, businesses are proving much slower in providing investors with robust information about their wider climate and carbon-related risks.

????Climate risk, along with the impact of carbon pricing, carries direct and indirect exposure for a company. It potentially affects its entire value chain, from production through to distribution and sales. Floods and blizzards disrupt suppliers and dislocate manufacturing, but they also can curb consumption.

????Over the long-term, extreme weather can damage both profitability and asset valuations in unexpected ways. Companies that fail to take account of these risks may suffer significant stress and have little flexibility to manage their exposure.

????Companies frequently focus on communicating their direct liability to carbon emissions regulation, notably the net cost of carbon permits they are required to hold under emissions trading schemes. These costs are important and, notwithstanding the recent decline in carbon credit prices, are likely to grow over time. But many companies ignore the – potentially much larger – costs of a carbon liability being passed down the supply chain or changing end demand for products and services.