Weather Matters
The Impact of Climate, Weather and Seasons on Economic Activity

Michael P. Niemira
RESEARCH REVIEW, V.12, NO.2, 2005 23

    Weather is a powerful force effecting the economy. No doubt about it. Abnormal weather conditions can shift the timing of purchases or it can result in a total loss of demand. But, to be meaningful to a geographically diverse country such as the United States, the impact has to widespread.


    Weather is a risk factor for business and government. Retailers often talk about how adverse weather impacts their sales and/or earnings. Witness, for example, the July 6, 2005,statement on second-quarter earnings by Peter Harris, CEO of West Marine, who said of his company’s sales:“As one would expect, continuing poor weather in April and May on both coasts dampened second quarter sales, especially when compared to the great spring weather we enjoyed last year. Unlike last year, many boats in our Northeast region, from the mid-Atlantic up through the northeastern seaboard and across to the Great Lakes, remained in storage until June. Although sales picked up along with better weather in June, we still had a disappointing second quarter.”

    天气对商业和政府都是一个风险因素。零售商经常谈到怎样改变天气对他们销售和/或收入的影响。例如:2005年6月6日西海(West Marine)的最高行政长官Peter Harris公布二季度的收入状况,他说:“如预料的那样,在持续恶劣天气的4-5月,这个公司二季度的销售令人沮丧的下滑,尤其与去年我们满意的大好的春天天气相比。与去年不同,在我们东北部地区(从大西洋中部到东北海岸并穿过五大湖)很多船的库存保持到六月。虽然销售随着六月天气的好转

    But weather matters to more than just retailers, and it can have secondary or indirect impacts on consumer spending. On March 14, 1978, Raymond Scheppach of the Congressional Budget Office testified before Congress:

    1978年3月14日国会预算办公室Raymond Scheppach在会前作证:对零售商关系更大的是天气对顾客的消费有继发的或间接的影响。

    Weather is an uncontrollable variable that directly and indirectly affects the federal budget. . . .The effects of weather on various budget accounts can be classified according to the type of weather sensitivity as follows: direct, indirect, and timing. Direct effects are those in which outlays and, at times, budget authority are affected directly by weather. Disaster payments to farmers for crop losses and unemployment compensation paid to workers who have been laid off because of a weather related shortage of natural gas are examples. An indirect impact is one that changes budget outlays through the inflation rate as generally reflected in the Consumer Price Index (CPI). For example, a crop loss causes food prices to increase, which in turn increases the overall CPI. Ultimately, such a change in the inflation rate is reflected in the federal budget through the various indexed entitlement programs, such as social security, railroad retirement, etc. The final kind of weather induced budget effects are those that affect the timing, but not the total level, of expenditures. These are primarily construction-related accounts in which bad weather restricts construction activity and federal outlays, but generally the activity and outlays are made up when the weather improves. Prime examples of this type of activity would be highway construction and the Environmental Protection Agency waste water treatment construction program.

种与提名的项目挂钩的指数反映在联邦预算中。例如:社会安全、铁路的退休等。最后一种天气影响预算是影响进度而非支出的总水平。坏天气约束建设活动和联邦费用的有关帐户的主要建筑 一般当天气好转时活动和费用被补足。这些活动类型的主要例子应是高速公路建设和“环境保护代理”的废水处理的建设项目。

    Scheppach’s perspective on the direct, indirect and timing impacts of weather on the budget also is helpful in understanding how weather impacts consumer spending.




    In assessing weather effects on consumer and business activity, there are three basic aspects to consider:(1) “weather as noise” and its role in shifting the timing of purchases or production (temporary impact); (2) “weather as a seasonal shock” and the possibility of a permanent impact on demand and output; and (3) “weather cycles” and a potentially causal relationship with macroeconomic activity.

    评估天气对消费者和商业活动的影响,要考虑三个基本方面:(1)“象燥声样天气”改变购物或生产的时间(临时影响);(2)“象周期性震荡的天气”,对需求 产量有可能永久性的影响;(3)“天气周期”是个与宏观经济活动关联的潜在的原因。

    In all three cases, it is not surprising that weather impacts economic activity—even if most economists do not explicitly consider that impact significant. Nonetheless, Nobel Prize winner Clive Granger (1978) wrote: “… actual changes in temperature, rainfall, and other weather variables have direct effects on various economic series, such as those concerned with agricultural production, construction, and transportation, and consequent indirect effects on other series. It could be argued that this cause is the true seasonal, being itself a
consequence of the annual movement of the earth’s axis which leads to the seasons.” It may be more surprising, however, that for the United States—which is geographically diverse—there is a macroeconomic impact from adverse weather, especially given that the U.S. Department of Commerce concluded in 1965 that its own “study attempted to isolate the impact of weather conditions on the irregular factor of retail sales but the geographic dispersion was too great and no practical application was possible.”

    所有这三种情况,可以毫不奇怪的认为:天气影响经济活动,尽管有许多经济学家不是明确的认为这些影响有重大的意义。尽管如此,诺贝尔奖获得者Clive Granger (1978)写道:“实际改变温度、降雨量和其它天气变量已经直接地影响了经济系列的各个方面。如关系到农业生产、建筑和运输并且对其他系列直接影响的结果。季节周期性转换的真正原因是地球轴每年运动的结果,这个也许有争议。”这令人吃惊,然而,对地理变化多的美国,1965年商务部论断:承认不利的天气对宏观经济影响,“努力研究天气条件对零售销售不规则因素单独的影响,但由于地域差异这么大可能无实用价值。”

    However, theory, data and empirical studies have come a long way. Robert Barsky and Jeffrey Miron (1989) suggest, for example, that the true macroeconomic link is from abnormal weather to the seasonal cycle to the business cycle. Those researchers further found that “seasonal fluctuations are an important source of variation in all macroeconomic quantity variables, including consumption, investment, government purchases, employment and the money stock. On the other hand, seasonal fluctuations are small or absent on both real and nominal price variables. . . . We suspect that the weather plays an important role in the [process].” The significance of this linkage should not be understated, as Barsky and Miron observed that “the similarity of the seasonal cycle and the business cycle presents a challenge because it suggests the possibility of a unified explanation of both business cycles and seasonal cycles.”

    不管怎么说,理论、资料和经验的研究已经走过了很常的路。如: Robert Barsky and Jeffrey Miron (1989)曾提出:“真正的宏观经济链是反常天气与季节周期及商业周期的关联。”这些研究者又进一步发现:“季节波动是所有宏观经济变量变异的重要来源,包括消费、投资、政府采购、就业和货币存量。另一方面,不动产和名义价格变量的季节波动是小的或不存在的……。我们猜想天气在这过程中扮演了一个重要的角色。”这种联想的意义应是不简单的,正如Barsky和Miron的观察:“因为季节周期与商业周期的类似,就出现了一个挑战,即暗示统一解释商业周期和季节周期的可能性。”



    In Nobel Prize winner Milton Friedman’s permanent income hypothesis, he posits that consumption and income can be segmented into two parts: a permanent component and a transitory component. Friedman wrote that the transitory component could be the result of,among other things, “unusually good or bad weather.” But the basis of this theory and other consumption theories following a similar line of reasoning is that if income—either permanent or transitory—does not change, then any increase or decrease in transitory consumption associated with abnormal weather will be reversed in the subsequent period or periods. Yet,still, there is a debate within the economics literature as to whether lost output or sales due to a shock is “permanent” or “transitory.” No truer is this concern evident when unseasonable weather impacts consumer spending. Are retail sales permanently lost or do they simply shift into some future date?

    诺贝尔奖获得者Milton Friedman的永久收益假设:他将消费和收入分割为两个部分:永久成分的和短成分的。Friedman写道:短期成分可能是由“特别好或坏天气”引起的。但是基于这个理论和其它消费理论有相似的推论:如果收入不改变,不管是永久的还是短期的,与不正常天气有关的短期消费的增加或减少将在后来的时期或周期中反转。然而,在经济文献中,对天气短期或永久的打击使产量或销售减少的论断仍有争论。不合季节的天气明显影响顾客消费

    Fabian Linden (1962) observed that those retail sales can be permanently lost due tounseasonable weather. Moreover, his study concluded that “weather has a powerful effect on demand.” Martha Starr-McCluer (2000) also points out that weather affects non-market activities (such as shopping or recreation time); yet, in the end, she concluded that the weather’s impact on retail sales “tends to wash out at a quarterly frequency.” While the Starr-McCluer conclusion is traditional, it may be too simplistic. In a series of papers by Barsky and Miron, Miron, and Beaulieu and Miron, the authors found that the seasonal cycle displays similar characteristics to the business cycle in the United States and internationally.Barsky and Miron (1989) concluded that “weather plays an important role in the [seasonal] recovery of [national output] from the first to the second quarter.” The assumption is that the seasonal cycle has reasonably fixed attributes, such as with the timing of holidays, weather patterns, factory shutdown periods, auto model production changeover schedules, and so on.In most cases, this is a reasonable assumption when it comes to holidays such as Christmas,but it is not true when it comes to other holidays such as Easter. The retail industry has long observed that the earlier in the year Easter occurs, the smaller the sales impact; in many cases, the seasonal cycle is not neutral over the year.

    Fabian Linden (1962)观察:由于不合季节的天气可能使零售销售永久性的丢失。而且,他研究推论“天气有能力影响需求”。Martha Starr-McCluer (2000)也指出:天气影响非市场行为(如:购物或娱乐时间),最终,她断定天气对零售销售的影响“往往在一个季度中冲击数次”。虽然Starr-McCluer的结论是传统的切如此的简单化。在Barsky与Miron、Miron与Beaulieu和 Miron的一系列著作中,作者们发现在美国和国际上季节周期对商业周期表现为类似的特征。
Barsky and Miron (1989)推断“在二季度初天气对全国产量季节性恢复表现为一个重要的角色”。假设季节周期有固有的特征,如:定期的休假日、天气模式、工厂停工期、汽车生产模式的改变的时间表等等。在大多数情况下,当一个节日如圣诞节来临时这是一个合理假设,但另一个节日如复活节来临时这却是不确定的。零售业已观察很久今年复活节前出现的零售销售很小的影响。在大多数情况下季节周期全年是确定的。



    One reason to believe that abnormal weather can have a lingering effect on the economy isthe building scientific evidence that an El Nifio(EN) or the Southern Oscillation (SO)—often referred to as “ENSO“—is a multi-year cycle of interaction between the atmosphere and the ocean, which produces a large-scale abnormal warming in sea surface temperatures found primarily in the tropical Pacific (see Chart 6-1). During ENSO periods, abnormal weather patterns may develop around the world. Similarly, a La Nifio is a multi-year period when there is a cooling in sea temperatures, which can result with the opposite effects from the ENSO. Table 6-1 presents the El Nifio periods. The most severe El Niifio on record occurred in 1982–1983, and was associated directly with $1.3 billion in flood damage in the United States alone. The 1994–1995 El Nifio was mild, on the other hand, and was associated with one of the warmest winters in the United States on record and unusually wet conditions in the West (especially in California).

    有理由相信反常天气可对经济有延缓的影响正被建立科学证据。El Nifio(EN)或Southern Oscillation (SO)经常提供“ENSO“—— 一种大气与海洋交互的多年循环周期,它最早在热带太平洋被发现的海洋表面温度产生大规模非正常的升高(见图6-1)。在‘ENSO“周期中,非正常天气模式可能在全世界展开。同样,La Nifio是一个多年的海洋温度冷却的时期。它引起的后果与ENSO的影响相反。表6-1表明El Nifio期。最严重的El Nifio的记录出现在1982-1983年。单在美国它与13亿美元的洪水灾害损失直接有关。1994–1995年El Nifio是温和的,它与美国创记录的最暖的暖冬有关,而且在西部出现不寻常的潮湿环境。(尤其在加里福尼亚)

    What does the presence of an El Nifio mean for retailers and other weather-sensitive businesses?

    EI Nitro的存在对零售商和其他天气敏感的商业意味着什么?

    The record qualitatively shows that overall U.S. consumer spending tends to be stronger in the early stages of an El Nifio. This may be due partly to, and initially from, less nondiscretionary spending on energy, for example, and more spending on other discretionary items. Moreover, it takes about 9–12 months for the impact of the warming in the Pacific Ocean (as reflected by the Southern Oscillation Index) to show up as abnormally wet weather over a widespread area of the United States. The sunspot cycle might be another reason for expecting longer-run impacts climate on the economy. Galileo was credited with discovering sunspots around 1610. Ever since that time, there has been a debate, which at times has been intense, on the effect of solar activity on man, weather, agriculture and the whole economy. The cycle in sunspot activity, however, was not fully appreciated until Heinrich Schwabe published a paper on the subject in 1844 and concluded that there was a reasonably periodic cycle in sunspot activity. Hence, the sunspot cycle is often dubbed the Schwabe cycle. Based on a thorough review of the scientific literature on the sun and its impact on weather, John Herman and Richard Goldberg (1978) concluded: (1) “the amount of annual rainfall . . . exhibits a dependence on the 11 year sunspot cycle in many land areas of the world”; (2) “long-term variations in surface temperature show some relationship with [the] sunspot cycle”; and (3) “sunspots are either a barometer for changes in solar [activity] or reflect direct processes related to solar activity which interact with the Earth’s atmosphere to affect weather and climate.” Moreover, Herman and Goldberg suggest that the consensus of spectral analysis studies (a cycle-length determining statistical technique) has found that the major periodicities in sunspots are at average cycle durations of 5.5, 8.1, 9.7, 11.2, 100 and 180 years.

    可靠的记录显示:全美消费者消费倾向在EI Nifio早期较强劲。开始阶段应付部分少数属刚性支出,如能耗。更多的支出属可自行选择的内容。此外,受太平洋海域升温的影响约持续9-12个月(摘自the Southern Oscillation Index)表现为异常的潮湿天气弥漫美国广泛的地区。太阳黑子周期可能是气候对经济更长期影响的另一个原因。可以认为Galileo发现太阳黑子周期大约在1610年。从那时至今,太阳活动对人、天气、农业和整个经济的影响一直有争论,有时很激
烈。然而,直到1844年Heinrich Schwabe出版这个主题的文献前,太阳黑子活动周期还未被完全认识,他推断太阳黑子活动有一定的循环周期。因此,太阳黑子周期常被称为施瓦布周期(Schwabe Cycle)。基于对太阳和它对天气影响科学文献的全面回顾,John Herman和RichardGoldberg(1978)论断:(1)“年降雨量……它的表现在世界许多地区和国家是根据11年太阳黑子周期”;(2)“水面温度长期的变化显示与太阳黑子周期有关”;(3)“太阳黑子要

    An early comprehensive attempt to incorporate the Schwabe cycle into a business cycle framework was suggested by William Stanley Jevons (1835–1882), who early in his career was a practicing meteorologist. In Jevons’Investigations in Currency and Finance, he discussed economic fluctuations and isolated three components of economic activity: seasonal fluctuation, business cycles and trends. Jevons attempted to statistically link the business cycle with fluctuations in sunspot activity. There was additional research by Jevons’son, H.S. Jevons, who further observed that “among other meteorological cycles, there exists a three-and-one-half-year period in solar radiation and barometric pressure,” which might help to explain the shorter-term business cycle. But despite the ongoing scientific research on sunspots, the economics profession has generally dismissed sunspots as a factor influencing the business cycle, largely because of some statistical problems with Jevons’ early study. Nonetheless, the cycle in sunspots is often linked to a climatic cycle, which has four major phases: warm-wet, warm-dry, cold-wet and cold-dry. Between the mid-1930s and mid-1950s,Raymond H. Wheeler, who was a professor of psychology at the University of Kansas,examined the role that those climatic phases had on human activities, including business activity. Michael Zahorchak (1983)summarized the Wheeler evidence as follows: While the causes of the business cycle vary, the common thread throughout all of the cycles is weather, and that no economic theory is complete without a weather component that can contribute a stimulating and debilitating effect on the economy. Wheeler did not advocate weather as the only cause of the business cycle—rather as a significant contributing factor. Wheeler’s work is an extension of earlier research by Ellsworth Huntington (1919), who suggested that variations in health caused the business cycle. Huntington felt that weather and solar radiation had critical influences on health. Wheeler and Huntington downplayed the weather/agricultural cycle connection with the economy and argued instead that “weather trends affect people directly, and [people are affected] only incidentally through crops.” The sunspot cycle is shown in Chart 6-2. In the final analysis, Edward Dewey (1968) summarized the empirical research on the relationship between sunspots and the economic cycle when he wrote: “. . . in spite of numerous allegations and widespread folklore, there is, as yet, no conclusive evidence that the dominant 11-year sunspot cycle, or the double sunspot cycle of 22 years, or any of the subsidiary solar cycles that have been alleged, have any economic or sociological repercussions.” And that is where the evidence largely still stands.

    早期努力将施瓦布周期并入商业周期的框架由早期是实习气象学家的William Stanley Jevons (1835–1882)提出。在他“流通与金融的研究”一文中,他讨论了经济波动和经济活动独立的三个内容:季节性波动、商业周期和趋势。他还努力统计商业周期与太阳黑子活动波动的关系。另外有由Jevons的儿子H.S. Jevons的研究。他进一步观察:“在其它气象周期中,有一个三年半的太阳辐射和大气压的周期”,着也许有助于解释短期的商业周期。尽管对太阳黑子还在科学研究中,但是经济学专家一般已经撇开太阳黑子作为影响商业周期的一个因素。最大的原因是由于Jevons早期研究的一些统计问题。但是,太阳黑子周期常常与气候周期有关系,这可分为四种主要状态:热-湿、热-干、冷-湿和冷-干。二十世纪三十年代中到五十年代中,堪萨斯大学的心理学教授Raymond H. Wheeler调查这些气候状态对人类活动,包括商业活动的影响。Michael Zahorchak (1983)概括了Wheeler的如下证据:当通常贯穿全部周期的商业周期变化的原因是天气。能对经济产生刺激和衰退影响中如没有天气因素,那么没有一种经济理论是完善的。Wheeler不主张将天气做为商业周期的唯一原因,而仅是个有意义的作用因素。Wheeler的工作是Ellsworth Huntington (1919) 更早研究的继续。他提出健康的变化引起商业周期。Huntington觉得天气和太阳辐射对人体健康有危险的影响。Wheeler和Huntington不重视天气/农业周期与经济的关系。“天气趋势直接影响人类并附带通过农作物再影响到人类”。太阳黑子周期见图6-2。Edward Dewey (1968)曾总结太阳黑子与经济周期两者关系的实验研究。他写道:“……面对众多指责和普遍的传说,但目前还没有确凿的证据表明,主导11年的太阳黑子周期或双黑子周期22年,或者任何附属太阳周期所声称的那样,有任何经济或社会反响。”证据应是有效的。



    This article reviewed the literature on shifts in weather, climate and the seasons, as well as their potential impact on consumer spending and, more generally, the economy. Although the empirical evidence for longer-term climate or weather cycles affecting consumer spending is still inconclusive, there are plenty of reasons to expect that there is some relationship between abnormal weather and changes in typical consumer spending behavior.